WorldWideScience

Sample records for research s-pol radar

  1. Research at the Stanford Center for Radar Astronomy

    Science.gov (United States)

    1972-01-01

    The research is reported in the applications of radar and radio techniques to the study of the solar system, and to space programs. Experiments reported include: bistatic-radar on Apollo missions, development of an unmanned geophysical observatory in the Antartic, Bragg scattering probes of sea states, characteristics of dense solar wind disturbances, and satellite communications for Alaska.

  2. MAJOR SOURCE OF NEW RADAR DATA FOR EXPLORATION RESEARCH.

    Science.gov (United States)

    Kover, Allan N.; Jones, John Edwin; Southworth, C. Scott

    1984-01-01

    In 1980, the U. S. Geological Survey (USGS) initiated a program to acquire high-quality, side-looking, airborne-radar (SLAR) imagery of selected areas of the United States. The program goals were to demonstrate the usefulness of SLAR imagery for geologic exploration and geoscience applications and to make radar data readily available to the public for additional research and economic applications. Considerable SLAR imagery has been acquired already since 1980 under a mandate from the U. S. Congress. The U. S. Geological Survey is actively engaged in demonstrating the usefulness of radar imagery, and since 1980 has started more than 50 studies addressing geologic, cartographic, and hydrologic applications. All of the radar-imagery products acquired by the USGS during 1980 and 1982 have been archived and are available for public sale.

  3. UAV-Borne Profiling Radar for Forest Research

    Directory of Open Access Journals (Sweden)

    Yuwei Chen

    2017-01-01

    Full Text Available Microwave Radar is an attractive solution for forest mapping and inventories because microwave signals penetrates into the forest canopy and the backscattering signal can provide information regarding the whole forest structure. Satellite-borne and airborne imaging radars have been used in forest resources mapping for many decades. However, their accuracy with respect to the main forest inventory attributes substantially varies depending on the wavelength and techniques used in the estimation. Systems providing canopy backscatter as a function of canopy height are, practically speaking, missing. Therefore, there is a need for a radar system that would enable the scientific community to better understand the radar backscatter response from the forest canopy. Consequently, we undertook a research study to develop an unmanned aerial vehicle (UAV-borne profiling (i.e., waveform radar that could be used to improve the understanding of the radar backscatter response for forestry mapping and inventories. A frequency modulation continuous waveform (FMCW profiling radar, termed FGI-Tomoradar, was introduced, designed and tested. One goal is the total weight of the whole system is less than 7 kg, including the radar system and georeferencing system, with centimetre-level positioning accuracy. Achieving this weight goal would enable the FGI-Tomoradar system to be installed on the Mini-UAV platform. The prototype system had all four linear polarization measuring capabilities, with bistatic configuration in Ku-band. In system performance tests in this study, FGI-Tomoradar was mounted on a manned helicopter together with a Riegl VQ-480-U laser scanner and tested in several flight campaigns performed at the Evo site, Finland. Airborne laser scanning data was simultaneously collected to investigate the differences and similarities of the outputs for the same target area for better understanding the penetration of the microwave signal into the forest canopy

  4. The Use of Radar Imagery in Climatological Research. Resource Paper No. 21.

    Science.gov (United States)

    Williams, Aaron, Jr.

    Intended to supplement undergraduate college geography courses, this resource paper investigates the need and use of radar in weather phenomena research. Radar can be used to study weather phenomena over a wide area, thus improving the results of statistical analyses previously limited by inadequate data. Radar techniques are also useful for…

  5. National High Frequency Radar Network (hfrnet) and Pacific Research Efforts

    Science.gov (United States)

    Hazard, L.; Terrill, E. J.; Cook, T.; de Paolo, T.; Otero, M. P.; Rogowski, P.; Schramek, T. A.

    2016-12-01

    The U.S. High Frequency Radar Network (HFRNet) has been in operation for over ten years with representation from 31 organizations spanning academic institutions, state and local government agencies, and private organizations. HFRNet currently holds a collection from over 130 radar installations totaling over 10 million records of surface ocean velocity measurements. HFRNet is a primary example of inter-agency and inter-institutional partnerships for improving oceanographic research and operations. HF radar derived surface currents have been used in several societal applications including coastal search and rescue, oil spill response, water quality monitoring and marine navigation. Central to the operational success of the large scale network is an efficient data management, storage, access, and delivery system. The networking of surface current mapping systems is characterized by a tiered structure that extends from the individual field installations to local regional operations maintaining multiple sites and on to centralized locations aggregating data from all regions. The data system development effort focuses on building robust data communications from remote field locations (sites) for ingestion into the data system via data on-ramps (Portals or Site Aggregators) to centralized data repositories (Nodes). Centralized surface current data enables the aggregation of national surface current grids and allows for ingestion into displays, management tools, and models. The Coastal Observing Research and Development Center has been involved in international relationships and research in the Philippines, Palau, and Vietnam. CORDC extends this IT architecture of surface current mapping data systems leveraging existing developments and furthering standardization of data services for seamless integration of higher level applications. Collaborations include the Philippine Atmospheric Geophysical and Astronomical Services Administration (PAGASA), The Coral Reef Research

  6. Global Research Patterns on Ground Penetrating Radar (GPR)

    Science.gov (United States)

    Gizzi, Fabrizio Terenzio; Leucci, Giovanni

    2018-05-01

    The article deals with the analysis of worldwide research patterns concerning ground penetrating radar (GPR) during 1995-2014. To do this, the Thomson Reuters' Science Citation Index Expanded (SCI-EXPANDED) and the Social Sciences Citation Index accessed via the Web of Science Core Collection were the two bibliographic databases taken as a reference. We pay attention to the document typology and language, the publication trend and citations, the subject categories and journals, the collaborations between authors, the productivity of the authors, the most cited articles, the countries and the institutions involved, and other hot issues. Concerning the main research subfields involving GPR use, there were five, physical-mathematical, sedimentological-stratigraphical, civil engineering/engineering geology/cultural heritage, hydrological (HD), and glaciological (GL), subfields.

  7. New Cloud and Precipitation Research Avenues Enabled by low-cost Phased-array Radar Technology

    Science.gov (United States)

    Kollias, P.; Oue, M.; Fridlind, A. M.; Matsui, T.; McLaughlin, D. J.

    2017-12-01

    For over half a century, radars operating in a wide range of frequencies have been the primary source of observational insights of clouds and precipitation microphysics and dynamics and contributed to numerous significant advancements in the field of cloud and precipitation physics. The development of multi-wavelength and polarization diversity techniques has further strengthened the quality of microphysical and dynamical retrievals from radars and has assisted in overcoming some of the limitations imposed by the physics of scattering. Atmospheric radars have historically employed a mechanically-scanning dish antenna and their ability to point to, survey, and revisit specific points or regions in the atmosphere is limited by mechanical inertia. Electronically scanned, or phased-array, radars capable of high-speed, inertialess beam steering, have been available for several decades, but the cost of this technology has limited its use to military applications. During the last 10 years, lower power and lower-cost versions of electronically scanning radars have been developed, and this presents an attractive and affordable new tool for the atmospheric sciences. The operational and research communities are currently exploring phased array advantages in signal processing (i.e. beam multiplexing, improved clutter rejection, cross beam wind estimation, adaptive sensing) and science applications (i.e. tornadic storm morphology studies). Here, we will present some areas of atmospheric research where inertia-less radars with ability to provide rapid volume imaging offers the potential to advance cloud and precipitation research. We will discuss the added value of single phased-array radars as well as networks of these radars for several problems including: multi-Doppler wind retrieval techniques, cloud lifetime studies and aerosol-convection interactions. The performance of current (dish) and future (e-scan) radar systems for these atmospheric studies will be evaluated using

  8. Research and development of laser radar for environmental measurement. 2; Kankyo keisokuyo laser radar no kenkyu kaihatsu. 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    This project was received by Optoelectronic Industry and Technology Development Association from NEDO, and aims to contribute to the improvement of Indonesia's environmental administration through the development of an air pollution observing laser radar (LR) and of an environmental information network system fit for use in the country in cooperation with Indonesian engineers. LRs will be installed at several sites in an urban area where environmental problems are increasingly serious, and a observation network system will be constructed to link the laser radar sites. The observed data will be collected, analyzed, and processed by an observation data processing center for the investigation of the three-dimensional spatial distribution of air pollution to determine the actual state of air pollution over an urban area. The laser radars and the network will be placed in the city of Djakarta. The Indonesian authority responsible for the project is Indonesian Institute of Sciences. In fiscal 1994, part of the equipment (difference absorbing LR) was designed and manufactured, the design of the environmental information network system was developed, and various researches required in this connection were conducted. (NEDO)

  9. Making the Most of What We Have Got: Enhancing the RADAR Repository to Support Research Planning

    Science.gov (United States)

    Pike, Dawn; Siminson, Nicola Jane

    2017-01-01

    This article discusses how RADAR, the institutional repository (IR) at the Glasgow School of Art (GSA), has been modified to house an Annual Research Planning (ARP) template. A case study on the implementation of this research planning tool will outline the role that a repository and its staff can play in supporting individuals, enhancing…

  10. Design and use of a mobile, x-band, high range resolution, radar research facility

    CSIR Research Space (South Africa)

    De Witt, JJ

    2012-10-01

    Full Text Available industries of the Centre for Science and Industrial Research (CSIR) (South Africa) and King Abdul Aziz City for Science and Technology (KACST) (Saudi Arabia). The radar employs true wideband processing in its complete RF and IF chain, supporting instantaneous...

  11. Novel radar techniques and applications

    CERN Document Server

    Klemm, Richard; Lombardo, Pierfrancesco; Nickel, Ulrich

    2017-01-01

    Novel Radar Techniques and Applications presents the state-of-the-art in advanced radar, with emphasis on ongoing novel research and development and contributions from an international team of leading radar experts. This volume covers: Real aperture array radar; Imaging radar and Passive and multistatic radar.

  12. The RADAR Project—A Service for Research Data Archival and Publication

    Directory of Open Access Journals (Sweden)

    Angelina Kraft

    2016-03-01

    Full Text Available The aim of the RADAR (Research Data Repository project is to set up and establish an infrastructure that facilitates research data management: the infrastructure will allow researchers to store, manage, annotate, cite, curate, search and find scientific data in a digital platform available at any time that can be used by multiple (specialized disciplines. While appropriate and innovative preservation strategies and systems are in place for the big data communities (e.g., environmental sciences, space, and climate, the stewardship for many other disciplines, often called the “long tail research domains”, is uncertain. Funded by the German Research Foundation (DFG, the RADAR collaboration project develops a service oriented infrastructure for the preservation, publication and traceability of (independent research data. The key aspect of RADAR is the implementation of a two-stage business model for data preservation and publication: clients may preserve research results for up to 15 years and assign well-graded access rights, or to publish data with a DOI assignment for an unlimited period of time. Potential clients include libraries, research institutions, publishers and open platforms that desire an adaptable digital infrastructure to archive and publish data according to their institutional requirements and workflows.

  13. Research cooperation of the development of laser radar for environmental measurements; Kankyo keisokuyo laser radar no kaihatsu ni kansuru kenkyu kyoryoku

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    Research and development of the laser radar for measuring the air pollution in urban areas and the environmental information network have been conducted through the cooperation with Indonesian researchers. A measurement system suitable to actual situation of Indonesia has been constructed. In FY 1996, some works have been conducted as in the final fiscal year. To set the laser radar for environmental measurements and to make a plan of measurement research, conditions of air pollution in Indonesia and setting places of systems have been investigated. Opinions for the cooperation research have been exchanged with Indonesian researchers. Actual trends of the environmental measurements technology using laser radar have been surveyed. Indonesian researchers have been invited to learn operation and data processing of the system. One unit of MIE diffusion laser radar system has been designed and fabricated, and an additional data processing program has been made. The system has been delivered to Jakarta and installed. After the adjustment, performance tests have been conducted to complete the construction of the system. 3 refs., 72 figs., 10 tabs.

  14. Research cooperation in the development of laser radar for environmental measurements. Environmental network; Kankyo keisokuyo laser radar no kaihatsu ni kansuru kenkyu kyoryoku. Kankyo network

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    Among the research cooperation in the development of laser radar for environmental measurements with Indonesia between FY 1993 and FY 1996, results of the research and development of the environmental network are summarized. For the environmental information network, the Tokyo NOC is linked as an Internet connection point in Japan with the Jakarta NOC using an international dedicated line with a capacity of 64 Kbps. The Tokyo NOC is linked with domestic environmental information researchers using Internet. Thus, data stored in the data processing system of laser radar can be exchanged, information in both countries can be exchanged using E-mail, and data can be accumulated. For the research cooperation with Indonesia, research of path control and information relay server, research of effective transmission of data on the network, and research of multimedia communication have been conducted. The multimedia communication, distributed processing, and extension of dedicated line network using PPTP have been also conducted. 39 figs., 4 tabs.

  15. Research and development of laser radar for environmental measurements. Pt. 3; Kankyo keisokuyo laser radar no kenkyu kaihatsu. 3

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    Described herein are the results of the joint project between Japan and Indonesia to construct a new laser radar network system, which can three-dimensionally measure air pollution conditions in urban areas, in Djakarta. This joint project is implemented to elucidate the mechanisms involved in air pollution in the city, and thereby to contribute to environmental administration of Indonesia. This project is expected to give the basic approach to solution of environmental problems in urban areas, and eventually on a global scale, and hence to contribute to construction of the global network systems for environment-related information, which should be necessary in the near future. The (ODA Laser Radar Development Committee) is the deliberative body for the project, responsible for evaluating the project results. The project will be implemented on a 4-year plan from FY1993 to 1996. The activities in this year, the third year for the project, include on-the-spot survey, selection of the laser radar site, and development/improvement of the laser radar system. These results are described herein. (NEDO)

  16. Minimum redundancy MIMO radars

    OpenAIRE

    Chen, Chun-Yang; Vaidyanathan, P. P.

    2008-01-01

    The multiple-input multiple-output (MIMO) radar concept has drawn considerable attention recently. In the traditional single-input multiple-output (SIMO) radar system, the transmitter emits scaled versions of a single waveform. However, in the MIMO radar system, the transmitter transmits independent waveforms. It has been shown that the MIMO radar can be used to improve system performance. Most of the MIMO radar research so far has focused on the uniform array. However, i...

  17. Research and development cooperation project on environmental measurement using laser radar in fiscal 1994; Kankyo keisokuyo laser radar no kaihatsu ni kansuru kenkyu kyoryoku

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    The paper outlined activities in fiscal 1994 in the R and D cooperation project on a laser radar for environmental measurement. In the activities in fiscal 1994 of `the ODA laser radar development committee,` the committee held four meetings, two field surveys were carried out, and two researchers were invited from Indonesia. In the field survey, the environment in Jakarta city was investigated in terms of changes in population and number of the cars registered. Further, from data collected during 1994-1998 in the central Jakarta city, the following were made clear: the trend of a decrease in SO2, the trend of a rapid increase and an excess of NO2 content over the environmental standard, the status of pollution of which the level is close to the upper limit of the environmental standard of dust, etc. In the meeting of the policy study for the field survey at LIPI headquarters, Japan proposed a system which is constituted of a difference absorption laser radar, two Mie scattering laser radars, and a central processing unit. The sites proposed were studied in cooperation with Indonesia. 40 refs., 65 figs., 9 tabs.

  18. Linear feature extraction from radar imagery: SBIR (Small Business Innovative Research), phase 2, option 2

    Science.gov (United States)

    Milgram, David L.; Kahn, Philip; Conner, Gary D.; Lawton, Daryl T.

    1988-12-01

    The goal of this effort is to develop and demonstrate prototype processing capabilities for a knowledge-based system to automatically extract and analyze features from Synthetic Aperture Radar (SAR) imagery. This effort constitutes Phase 2 funding through the Defense Small Business Innovative Research (SBIR) Program. Previous work examined the feasibility of and technology issues involved in the development of an automated linear feature extraction system. This final report documents this examination and the technologies involved in automating this image understanding task. In particular, it reports on a major software delivery containing an image processing algorithmic base, a perceptual structures manipulation package, a preliminary hypothesis management framework and an enhanced user interface.

  19. Research and development cooperation project on environmental measurement using laser radar in fiscal 1995; Kankyo keisokuyo laser radar no kaihatsu ni kansuru kenkyu kyoryoku

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    For the purpose of contributing to the environmental management in Indonesia, Japan made R and D of a laser radar to measure the urban air pollution and an environmental network jointly with Indonesia in compliance with the actual situation of the country. At present, in developing countries, air pollution is becoming a big problem because of increases in population and in energy consumption in urban areas according to the industrial/economic growth. As for the laser radar, it is an active sensor with laser as light source and can observe in high resolution the three-dimensional space distribution such as density and composition of air pollutants. Japan is a leader in the development of laser technology which is a core technology for the laser radar and the preceding research. The equipment is installed at several points of urban areas in Indonesia, and at the same time, the observation network is constructed to collect, analyze and process data at the central processing center. This is a 4-year plan from fiscal 1993 to 1996. In fiscal 1995, negotiations with Indonesia and field surveys were conducted to determine sites for installation. A plan for system improvement was also decided on. 38 refs., 24 figs., 14 tabs.

  20. Adaptive radar resource management

    CERN Document Server

    Moo, Peter

    2015-01-01

    Radar Resource Management (RRM) is vital for optimizing the performance of modern phased array radars, which are the primary sensor for aircraft, ships, and land platforms. Adaptive Radar Resource Management gives an introduction to radar resource management (RRM), presenting a clear overview of different approaches and techniques, making it very suitable for radar practitioners and researchers in industry and universities. Coverage includes: RRM's role in optimizing the performance of modern phased array radars The advantages of adaptivity in implementing RRMThe role that modelling and

  1. The Goldstone solar system radar: A science instrument for planetary research

    Science.gov (United States)

    Dvorsky, J. D.; Renzetti, N. A.; Fulton, D. E.

    1992-01-01

    The Goldstone Solar System Radar (GSSR) station at NASA's Deep Space Communications Complex in California's Mojave Desert is described. A short chronological account of the GSSR's technical development and scientific discoveries is given. This is followed by a basic discussion of how information is derived from the radar echo and how the raw information can be used to increase understanding of the solar system. A moderately detailed description of the radar system is given, and the engineering performance of the radar is discussed. The operating characteristics of the Arcibo Observatory in Puerto Rico are briefly described and compared with those of the GSSR. Planned and in-process improvements to the existing radar, as well as the performance of a hypothetical 128-m diameter antenna radar station, are described. A comprehensive bibliography of referred scientific and engineering articles presenting results that depended on data gathered by the instrument is provided.

  2. Linear feature extraction from radar imagery: SBIR (Small Business Innovative Research) phase 2, option 1

    Science.gov (United States)

    Conner, Gary D.; Milgram, David L.; Lawton, Daryl T.; McConnell, Christopher C.

    1988-04-01

    The goal of this effort is to develop and demonstrate prototype processing capabilities for a knowledge-based system to automatically extract and analyze linear features from synthetic aperture radar (SAR) imagery. This effort constitutes Phase 2 funding through the Defense Small Business Innovative Research (SBIR) Program. Previous work examined the feasibility of the technology issues involved in the development of an automatedlinear feature extraction system. This Option 1 Final Report documents this examination and the technologies involved in automating this image understanding task. In particular, it reports on a major software delivery containing an image processing algorithmic base, a perceptual structures manipulation package, a preliminary hypothesis management framework and an enhanced user interface.

  3. Research and development cooperation project on environmental measurement using laser radar in fiscal 1993; Kankyo keisokuyo laser radar no kaihatsu ni kansuru kenkyu kyoryoku

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-03-01

    As one of the international research cooperation projects, the research cooperation in developing laser radar for environment measurement started between Japan and Indonesia. The project is scheduled to be carried out in a 4-year plan starting fiscal 1993. In fiscal 1993, conducted were negotiations with Indonesia on its implementation and a field survey. Between January 6 and 15, 1994, the first field survey was made in terms of topography, climate, road network and traffic situation of Jakarta city, and the proposed sites for installation were reported. The paper also introduced the reception system on the Indonesian side and a request for technical learning through stay in Japan. The second field survey was conducted between February 27 and March 6, 1994. Indonesia requested that they want to make laser radar observation not only for the local area, but the one that covers industrial areas, central urban areas and residential areas. Incidentally, there was an opinion that it is important to elucidate the pollution mechanism. 19 refs., 43 figs., 6 tabs.

  4. Radar remote sensing in biology

    Science.gov (United States)

    Moore, Richard K.; Simonett, David S.

    1967-01-01

    The present status of research on discrimination of natural and cultivated vegetation using radar imaging systems is sketched. The value of multiple polarization radar in improved discrimination of vegetation types over monoscopic radars is also documented. Possible future use of multi-frequency, multi-polarization radar systems for all weather agricultural survey is noted.

  5. Novel radar techniques and applications

    CERN Document Server

    Klemm, Richard; Koch, Wolfgang

    2017-01-01

    Novel Radar Techniques and Applications presents the state-of-the-art in advanced radar, with emphasis on ongoing novel research and development and contributions from an international team of leading radar experts. This volume covers: Waveform diversity and cognitive radar and Target tracking and data fusion.

  6. Characterization of Adolescent Prescription Drug Abuse and Misuse Using the Researched Abuse Diversion and Addiction-Related Surveillance (RADARS[R]) System

    Science.gov (United States)

    Zosel, Amy; Bartelson, Becki Bucher; Bailey, Elise; Lowenstein, Steven; Dart, Rick

    2013-01-01

    Objective: To describe the characteristics and health effects of adolescent (age 13-19 years) prescription drug abuse and misuse using the Researched Abuse Diversion and Addiction-Related Surveillance (RADARS[R])) System. Method: Secondary analysis of data collected from RADARS System participating poison centers was performed. Data for all…

  7. Case Study Analysis of Linear Chirp and Multitones (OFDM) Radar Signals Through Simulations and Measurement with HYCAM-Research Test Bench

    OpenAIRE

    Le Kernec, Julien; Dreuillet, Philippe; Bobillot, Gerard; Garda, Patrick; Romain, Olivier; Denoulet, Julien

    2009-01-01

    This paper presents a experimental platform that allows comparing objectively any radar waveforms. This is realized by equating radar characteristics, using the same test-bench HYCAM-Research, the same signal processing and also insuring the reproducibility of the experiments. The experimental measurements on linear chirp and multitones are analyzed through distance and velocity imaging.

  8. Current uses of ground penetrating radar in groundwater-dependent ecosystems research.

    Science.gov (United States)

    Paz, Catarina; Alcalá, Francisco J; Carvalho, Jorge M; Ribeiro, Luís

    2017-10-01

    Ground penetrating radar (GPR) is a high-resolution technique widely used in shallow groundwater prospecting. This makes GPR ideal to characterize the hydrogeological functioning of groundwater-dependent ecosystems (GDE). This paper reviews current uses of GPR in GDE research through the construction of a database comprising 91 worldwide GPR case studies selected from the literature and classified according to (1) geological environments favouring GDE; (2) hydrogeological research interests; and (3) field technical and (4) hydrogeological conditions of the survey. The database analysis showed that inland alluvial, colluvial, and glacial formations were the most widely covered geological environments. Water-table depth was the most repeated research interest. By contrast, weathered-marl and crystalline-rock environments as well as the delineation of salinity interfaces in coastal and inland areas were less studied. Despite that shallow groundwater propitiated GDE in almost all the GPR case studies compiled, only one case expressly addressed GDE research. Common ranges of prospecting depth, water-table depth, and volumetric water content deduced by GPR and other techniques were identified. Antenna frequency of 100MHz and the common offset acquisition technique predominated in the database. Most of GPR case studies were in 30-50° N temperate latitudes, mainly in Europe and North America. Eight original radargrams were selected from several GPR profiles performed in 2014 and 2015 to document database classes and identified gaps, as well as to define experimental ranges of operability in GDE environments. The results contribute to the design of proper GPR surveys in GDE research. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Civil Engineering Applications of Ground Penetrating Radar Recent Advances @ the ELEDIA Research Center

    Science.gov (United States)

    Salucci, Marco; Tenuti, Lorenza; Nardin, Cristina; Oliveri, Giacomo; Viani, Federico; Rocca, Paolo; Massa, Andrea

    2014-05-01

    The application of non-destructive testing and evaluation (NDT/NDE) methodologies in civil engineering has raised a growing interest during the last years because of its potential impact in several different scenarios. As a consequence, Ground Penetrating Radar (GPR) technologies have been widely adopted as an instrument for the inspection of the structural stability of buildings and for the detection of cracks and voids. In this framework, the development and validation of GPR algorithms and methodologies represents one of the most active research areas within the ELEDIA Research Center of the University of Trento. More in detail, great efforts have been devoted towards the development of inversion techniques based on the integration of deterministic and stochastic search algorithms with multi-focusing strategies. These approaches proved to be effective in mitigating the effects of both nonlinearity and ill-posedness of microwave imaging problems, which represent the well-known issues arising in GPR inverse scattering formulations. More in detail, a regularized multi-resolution approach based on the Inexact Newton Method (INM) has been recently applied to subsurface prospecting, showing a remarkable advantage over a single-resolution implementation [1]. Moreover, the use of multi-frequency or frequency-hopping strategies to exploit the information coming from GPR data collected in time domain and transformed into its frequency components has been proposed as well. In this framework, the effectiveness of the multi-resolution multi-frequency techniques has been proven on synthetic data generated with numerical models such as GprMax [2]. The application of inversion algorithms based on Bayesian Compressive Sampling (BCS) [3][4] to GPR is currently under investigation, as well, in order to exploit their capability to provide satisfactory reconstructions in presence of single and multiple sparse scatterers [3][4]. Furthermore, multi-scaling approaches exploiting level

  10. Analytical Research by Computer Simulation of Developmental Polarimetric/Frequency Agile Pulsed Radars.

    Science.gov (United States)

    1982-12-01

    scattering matrix format so that the entire radar signature will be available for future radar hardware and simulator designers . Without such data and...validated models the radar system analyst and designer will continue to suffer from the so called "Sedenquist Effect" that is, put two radar engineers...P4AsME 7Em VAMqA5OIE I uU04 I.ATEGE.4. VARIAdLE AVAL U00036 REAL*4 VAmIAdLE CAdS vu0uvi4 iKEA *4 sN(,CEOumE CUM"Uiv iLUC.A /AUOX L.Ei#GTH 04UOaUt HO0SAV

  11. Research on Radar Cross Section Measurement Based on Near-field Imaging of Cylindrical Scanning

    Directory of Open Access Journals (Sweden)

    Xing Shu-guang

    2015-04-01

    Full Text Available A new method of Radar Cross Section (RCS measurement based on near-field imaging of cylindrical scanning surface is proposed. The method is based on the core assumption that the target consists of ideal isotropic scattered centers. Three-dimensional radar scattered images are obtained by using the proposed method, and then to obtain the RCS of the target, the scattered far field is calculated by summing the fields generated by the equivalent scattered centers. Not only three dimensional radar reflectivity images but also the RCS of targets in certain three dimensional angle areas can be obtained. Compared with circular scanning that can only obtain twodimensional radar reflectivity images and RCS results in two-dimensional angle areas, cylindrical scanning can provide more information about the scattering properties of the targets. The method has strong practicability and its validity is verified by simulations.

  12. ''Swords into ploughshares'': Breaking new ground with radar hardware and technique in physical research after World War II

    International Nuclear Information System (INIS)

    Forman, P.

    1995-01-01

    A survey is offered of applications to fundamental physical research, in the years immediately following World War II, of the instrumentalities developed for radar during that war. Attention is given to radar astronomy and radio astronomy, linear and cyclical accelerators, microwave spectroscopy, molecular beams, nuclear magnetic resonance, electron paramagnetic and ferromagnetic resonance, measurements of resistivity at high frequencies in metals and of second sound in helium II, and to the concepts of information and signal-to-noise ratio as basic to the design and analysis of experiments. In conjunction with this survey, consideration is given to the autonomy of physics as a knowledge-producing enterprise, framed as a question of continuity in research directions. As that question implies a baseline, the survey of postwar applications is preceded by a survey of those prewar directions of physical research requiring the highest available radio frequencies. Some 500 references are given

  13. Bringing Student Research into the Classroom: An Example from a Course on Radar Interferometry

    Science.gov (United States)

    Schmidt, D. A.

    2011-12-01

    Student learning is enhanced through the hands-on experience of working with real data. I present an example where a course is designed around student research projects where the students process and interpret a data set. In this particular case, synthetic aperture radar (SAR) data is the chosen data product. The students learn several skills that are critical to being a good scientist, including how to formulate a project and motivate the objectives. The skills that are taught in the course represent transferable skills. For example, many of the students are exposed to the Unix environment for the first time. Students also learn how best to convey their findings in both written and oral formats. For many undergraduates, this course represents their first research experience where they are working with real data (and all the uncertainties and complexities therein), and the first time they are attempting to answer an open-ended research question. The course format is divided into two parts: (1) a series of lectures and homework assignments that teach the theoretical and technical aspects of radar interferometry, and (2) a series of lab periods where students develop the practical skills of working with the data in a Unix computing environment. Over the term, each student develops an independent research project where they identify a geologic process of interest (such as fault creep, land subsidence, volcanic inflation) and process SAR data over their chosen research target. Since the outcome of each student project is unknown prior to doing the work, the student experiences the thrill of discovery that comes with scientific research. The computational resources and course development was funded by the NSF Career Program, and SAR data was provided through the WInSAR Consortium. Student course reports are published online so that their findings can be shared with the broader community. This was done using a wiki, a server-side software that allows for the

  14. Research on the range side lobe suppression method for modulated stepped frequency radar signals

    Science.gov (United States)

    Liu, Yinkai; Shan, Tao; Feng, Yuan

    2018-05-01

    The magnitude of time-domain range sidelobe of modulated stepped frequency radar affects the imaging quality of inverse synthetic aperture radar (ISAR). In this paper, the cause of high sidelobe in modulated stepped frequency radar imaging is analyzed first in real environment. Then, the chaos particle swarm optimization (CPSO) is used to select the amplitude and phase compensation factors according to the minimum sidelobe criterion. Finally, the compensated one-dimensional range images are obtained. Experimental results show that the amplitude-phase compensation method based on CPSO algorithm can effectively reduce the sidelobe peak value of one-dimensional range images, which outperforms the common sidelobe suppression methods and avoids the coverage of weak scattering points by strong scattering points due to the high sidelobes.

  15. Research on Radar Micro-Doppler Feature Parameter Estimation of Propeller Aircraft

    Science.gov (United States)

    He, Zhihua; Tao, Feixiang; Duan, Jia; Luo, Jingsheng

    2018-01-01

    The micro-motion modulation effect of the rotated propellers to radar echo can be a steady feature for aircraft target recognition. Thus, micro-Doppler feature parameter estimation is a key to accurate target recognition. In this paper, the radar echo of rotated propellers is modelled and simulated. Based on which, the distribution characteristics of the micro-motion modulation energy in time, frequency and time-frequency domain are analyzed. The micro-motion modulation energy produced by the scattering points of rotating propellers is accumulated using the Inverse-Radon (I-Radon) transform, which can be used to accomplish the estimation of micro-modulation parameter. Finally, it is proved that the proposed parameter estimation method is effective with measured data. The micro-motion parameters of aircraft can be used as the features of radar target recognition.

  16. Doppler radar physiological sensing

    CERN Document Server

    Lubecke, Victor M; Droitcour, Amy D; Park, Byung-Kwon; Singh, Aditya

    2016-01-01

    Presents a comprehensive description of the theory and practical implementation of Doppler radar-based physiological monitoring. This book includes an overview of current physiological monitoring techniques and explains the fundamental technology used in remote non-contact monitoring methods. Basic radio wave propagation and radar principles are introduced along with the fundamentals of physiological motion and measurement. Specific design and implementation considerations for physiological monitoring radar systems are then discussed in detail. The authors address current research and commercial development of Doppler radar based physiological monitoring for healthcare and other applications.

  17. Mapping Fractures in KAERI Underground Research Tunnel using Ground Penetrating Radar

    Science.gov (United States)

    Baek, Seung-Ho; Kim, Seung-Sep; Kwon, Jang-Soon

    2016-04-01

    The proportion of nuclear power in the Republic of Korea occupies about 40 percent of the entire electricity production. Processing or disposing nuclear wastes, however, remains one of biggest social issues. Although low- and intermediate-level nuclear wastes are stored temporarily inside nuclear power plants, these temporary storages can last only up to 2020. Among various proposed methods for nuclear waste disposal, a long-term storage using geologic disposal facilities appears to be most highly feasible. Geological disposal of nuclear wastes requires a nuclear waste repository situated deep within a stable geologic environment. However, the presence of small-scale fractures in bedrocks can cause serious damage to durability of such disposal facilities because fractures can become efficient pathways for underground waters and radioactive wastes. Thus, it is important to find and characterize multi-scale fractures in bedrocks hosting geologic disposal facilities. In this study, we aim to map small-scale fractures inside the KAERI Underground Research Tunnel (KURT) using ground penetrating radar (GPR). The KURT is situated in the Korea Atomic Energy Research Institute (KAERI). The survey target is a section of wall cut by a diamond grinder, which preserves diverse geologic features such as dykes. We conducted grid surveys on the wall using 500 MHz and 1000 MHz pulseEKKO PRO sensors. The observed GPR signals in both frequencies show strong reflections, which are consistent to form sloping planes. We interpret such planar features as fractures present in the wall. Such fractures were also mapped visually during the development of the KURT. We confirmed their continuity into the wall from the 3D GPR images. In addition, the spatial distribution and connectivity of these fractures are identified from 3D subsurface images. Thus, we can utilize GPR to detect multi-scale fractures in bedrocks, during and after developing underground disposal facilities. This study was

  18. Research and development cooperation project on environmental measurement using laser radar (environmental network) in fiscal 1993; Kankyo keisokuyo laser radar no kaihatsu ni kansuru kenkyu kyoryoku (kankyo network)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-03-01

    For the purpose of contributing to the research cooperation project on the development of a laser radar for environmental measurement, the paper surveyed the present and future trend of the environment related information network in Indonesia. The survey was conducted in terms of a name of the network, the main administration body, the number of users, the utilization status, the use protocol, details of service, domestic mode installation sites and the main administration body, accounting system, types of the network used, reliability and stability of network, limitations on the use and details of the limitation, etc. The plan for expanding telecommunication equipment is being advanced in a very quick tempo. However, there are many problems in digitalization, and it is feared that the plan will be delayed. As to telecommunication quality and connection quality, the telecommunication completion rate, SCR, is very low, approximately 24% on average, which is equal to that around 1990 in Japan. The business service for users is all bureaucratic since they have a lot of applications for the installation piling up with no exception to the rule of developing countries. 23 figs., 10 tabs.

  19. Research and development cooperation project on environmental measurement using laser radar in fiscal 1995 (environmental network); Kankyo keisokuyo laser radar no kaihatsu ni kansuru kenkyu kyoryoku (kankyo network)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    As a part of the cooperative work with Indonesia of R and D of a laser radar for environmental measurement, the paper described the development of an environmental network. The field survey was conducted in April, July and December 1995 and in March 1996. For the investigational research, five meetings of the committee and four times of group work were held. The Asian environmental network was studied in terms of its arrangement, operation and management, and the overall network/path control design were being prepared. To make the persons concerned abroad and in Japan understood the APEC Osaka Conference held in November 1995, a homepage APEC `95 Kansai was opened using WWW (World Wide Web, a decentralized hyper media system which can dispatch information to the whole world by network using hyper text). Moreover, in connection with this, a homepage was opened of CICC (Center of the International Cooperation for Computerization, a center controlling the whole Asian environmental information network system where E-mail and data are exchangeable with Indonesia via Tokyo NOC (Network Operation Center)). 49 figs., 8 tabs.

  20. Quantum radar

    CERN Document Server

    Lanzagorta, Marco

    2011-01-01

    This book offers a concise review of quantum radar theory. Our approach is pedagogical, making emphasis on the physics behind the operation of a hypothetical quantum radar. We concentrate our discussion on the two major models proposed to date: interferometric quantum radar and quantum illumination. In addition, this book offers some new results, including an analytical study of quantum interferometry in the X-band radar region with a variety of atmospheric conditions, a derivation of a quantum radar equation, and a discussion of quantum radar jamming.This book assumes the reader is familiar w

  1. Civil Engineering Applications of Ground Penetrating Radar: Research Perspectives in COST Action TU1208

    Science.gov (United States)

    Pajewski, Lara; Benedetto, Andrea; Loizos, Andreas; Slob, Evert; Tosti, Fabio

    2013-04-01

    can be used by GPR operators to identify the signatures generated by uncommon targets or by composite structures. Repeated evaluations of the electromagnetic field scattered by known targets can be performed by a forward solver, in order to estimate - through comparison with measured data - the physics and geometry of the region investigated by the GPR. It is possible to identify three main areas, in the GPR field, that have to be addressed in order to promote the use of this technology in the civil engineering. These are: a) increase of the system sensitivity to enable the usability in a wider range of conditions; b) research novel data processing algorithms/analysis tools for the interpretation of GPR results; c) contribute to the development of new standards and guidelines and to training of end users, that will also help to increase the awareness of operators. In this framework, the COST Action TU1208 "Civil Engineering Applications of Ground Penetrating Radar", proposed by Lara Pajewski, "Roma Tre" University, Rome, Italy, has been approved in November 2012 and is going to start in April 2013. It is a 4-years ambitious project already involving 17 European Countries (AT, BE, CH, CZ, DE, EL, ES, FI, FR, HR, IT, NL, NO, PL, PT, TR, UK), as well as Australia and U.S.A. The project will be developed within the frame of a unique approach based on the integrated contribution of University researchers, software developers, geophysics experts, Non-Destructive Testing equipment designers and producers, end users from private companies and public agencies. The main objective of the COST Action TU1208 is to exchange and increase scientific-technical knowledge and experience of GPR techniques in civil engineering, whilst promoting the effective use of this safe and non-destructive technique in the monitoring of systems. In this interdisciplinary Action, advantages and limitations of GPR will be highlighted, leading to the identification of gaps in knowledge and technology

  2. Research cooperation project for fiscal 1998. Research cooperation on the research and development of environment measuring laser radar (Follow-up); 1998 nendo kankyo keisokuyo laser reda no kenkyu kaihatsu ni kansuru kenkyu kyoryoku. Flow up

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    Research and development of laser radars for observing urban atmospheric pollution is jointly conducted by Japan and Indonesia for the goal of contributing to the construction of an administrative system on environmental matters compatible with the actualities of Indonesia. Under this project, laser radars are installed at three sites in the city of Djakarta where environmental problems are increasingly serious, an observation network system is constructed connecting the laser radar sites, and the data are collected, analyzed, and processed by a data processing center. This enables the acquisition of information about the pollution of urban atmosphere through the observation of the 3-dimensional distribution of atmospheric pollution. In fiscal 1998, the last year for follow-up, engineers and researches are dispatched by 'ODA (official development assistance) laser radar observation assistance committee' for assistance in system maintenance and pollution observation. System maintenance is carried out so that the laser radar system may be utilized by the Indonesian party. Observation assistance involves Mie scattering, and the Indonesian party is engaged in a long-term continuous laser radar observation. (NEDO)

  3. Radar Chart

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Radar Chart collection is an archived product of summarized radar data. The geographic coverage is the 48 contiguous states of the United States. These hourly...

  4. The research of radar target tracking observed information linear filter method

    Science.gov (United States)

    Chen, Zheng; Zhao, Xuanzhi; Zhang, Wen

    2018-05-01

    Aiming at the problems of low precision or even precision divergent is caused by nonlinear observation equation in radar target tracking, a new filtering algorithm is proposed in this paper. In this algorithm, local linearization is carried out on the observed data of the distance and angle respectively. Then the kalman filter is performed on the linearized data. After getting filtered data, a mapping operation will provide the posteriori estimation of target state. A large number of simulation results show that this algorithm can solve above problems effectively, and performance is better than the traditional filtering algorithm for nonlinear dynamic systems.

  5. Radar Fundamentals, Presentation

    OpenAIRE

    Jenn, David

    2008-01-01

    Topics include: introduction, radar functions, antennas basics, radar range equation, system parameters, electromagnetic waves, scattering mechanisms, radar cross section and stealth, and sample radar systems.

  6. Radar equations for modern radar

    CERN Document Server

    Barton, David K

    2012-01-01

    Based on the classic Radar Range-Performance Analysis from 1980, this practical volume extends that work to ensure applicability of radar equations to the design and analysis of modern radars. This unique book helps you identify what information on the radar and its environment is needed to predict detection range. Moreover, it provides equations and data to improve the accuracy of range calculations. You find detailed information on propagation effects, methods of range calculation in environments that include clutter, jamming and thermal noise, as well as loss factors that reduce radar perfo

  7. Research on Debonding Defects in Thermal Barrier Coatings Structure by Thermal-Wave Radar Imaging (TWRI)

    Science.gov (United States)

    Wang, Fei; Liu, Junyan; Mohummad, Oliullah; Wang, Yang

    2018-06-01

    In this paper, thermal-wave radar imaging (TWRI) is introduced to detect debonding defects in SiC-coated Ni-based superalloy plates. Linear frequency modulation signal (chirp) is used as the excitation signal which has a large time-bandwidth product. Artificial debonding defects in SiC coating are excited by the laser beam with the light intensity modulated by a chirp signal. Cross-correlation algorithm and chirp lock-in algorithm are introduced to extract the thermal-wave signal characteristic. The comparative experiment between TWRI reflection mode and transmission mode was carried out. Experiments are conducted to investigate the influence of laser power density, chirp period, and excitation frequency. Experimental results illustrate that chirp lock-in phase has a better detection capability than other characteristic parameters. TWRI can effectively detect simulated debonding defects of SiC-coated Ni-based superalloy plates.

  8. Research on Synthetic Aperture Radar Processing for the Spaceborne Sliding Spotlight Mode.

    Science.gov (United States)

    Shen, Shijian; Nie, Xin; Zhang, Xinggan

    2018-02-03

    Gaofen-3 (GF-3) is China' first C-band multi-polarization synthetic aperture radar (SAR) satellite, which also provides the sliding spotlight mode for the first time. Sliding-spotlight mode is a novel mode to realize imaging with not only high resolution, but also wide swath. Several key technologies for sliding spotlight mode in spaceborne SAR with high resolution are investigated in this paper, mainly including the imaging parameters, the methods of velocity estimation and ambiguity elimination, and the imaging algorithms. Based on the chosen Convolution BackProjection (CBP) and PFA (Polar Format Algorithm) imaging algorithms, a fast implementation method of CBP and a modified PFA method suitable for sliding spotlight mode are proposed, and the processing flows are derived in detail. Finally, the algorithms are validated by simulations and measured data.

  9. Research on Synthetic Aperture Radar Processing for the Spaceborne Sliding Spotlight Mode

    Directory of Open Access Journals (Sweden)

    Shijian Shen

    2018-02-01

    Full Text Available Gaofen-3 (GF-3 is China’ first C-band multi-polarization synthetic aperture radar (SAR satellite, which also provides the sliding spotlight mode for the first time. Sliding-spotlight mode is a novel mode to realize imaging with not only high resolution, but also wide swath. Several key technologies for sliding spotlight mode in spaceborne SAR with high resolution are investigated in this paper, mainly including the imaging parameters, the methods of velocity estimation and ambiguity elimination, and the imaging algorithms. Based on the chosen Convolution BackProjection (CBP and PFA (Polar Format Algorithm imaging algorithms, a fast implementation method of CBP and a modified PFA method suitable for sliding spotlight mode are proposed, and the processing flows are derived in detail. Finally, the algorithms are validated by simulations and measured data.

  10. Air and spaceborne radar systems an introduction

    CERN Document Server

    Lacomme, Philippe; Hardange, Jean-Philippe; Normant, Eric

    2001-01-01

    A practical tool on radar systems that will be of major help to technicians, student engineers and engineers working in industry and in radar research and development. The many users of radar as well as systems engineers and designers will also find it highly useful. Also of interest to pilots and flight engineers and military command personnel and military contractors. """"This introduction to the field of radar is intended for actual users of radar. It focuses on the history, main principles, functions, modes, properties and specific nature of modern airborne radar. The book examines radar's

  11. Social Radar

    Science.gov (United States)

    2012-01-01

    RTA HFM-201/RSM PAPER 3 - 1 © 2012 The MITRE Corporation. All Rights Reserved. Social Radar Barry Costa and John Boiney MITRE Corporation...defenders require an integrated set of capabilities that we refer to as a “ social radar.” Such a system would support strategic- to operational-level...situation awareness, alerting, course of action analysis, and measures of effectiveness for each action undertaken. Success of a social radar

  12. Planetary Radar

    Science.gov (United States)

    Neish, Catherine D.; Carter, Lynn M.

    2015-01-01

    This chapter describes the principles of planetary radar, and the primary scientific discoveries that have been made using this technique. The chapter starts by describing the different types of radar systems and how they are used to acquire images and accurate topography of planetary surfaces and probe their subsurface structure. It then explains how these products can be used to understand the properties of the target being investigated. Several examples of discoveries made with planetary radar are then summarized, covering solar system objects from Mercury to Saturn. Finally, opportunities for future discoveries in planetary radar are outlined and discussed.

  13. COST Action TU1208 "Civil Engineering Applications of Ground Penetrating Radar:" ongoing research activities and mid-term results

    Science.gov (United States)

    Pajewski, Lara; Benedetto, Andrea; Loizos, Andreas; Slob, Evert; Tosti, Fabio

    2015-04-01

    .GPRadar.eu. Acknowledgement The Authors thank COST, for funding the Action TU1208 "Civil Engineering Applications of Ground Penetrating Radar." References [1] L. Pajewski, A. Benedetto, X. Dérobert, A. Giannopoulos, A. Loizos, G. Manacorda, M. Marciniak, C. Plati, G. Schettini, I. Trinks, "Applications of Ground Penetrating Radar in Civil Engineering - COST Action TU1208," Proc. 7th International Workshop on Advanced Ground Penetrating Radar (IWAGPR), 2-5 July 2013, Nantes, France, pp. 1-6 (INVITED). ISBN 978-1-4799-0937-7, doi:10.1109/ IWAGPR.2013.6601528). [2] L. Pajewski, A. Benedetto, "Advanced Ground Penetrating Radar: open issues and new research opportunities in Europe," Proc. 10th European Radar Conference (EuRad), 2013 European Microwave Week (EuMW), 6-11 October 2013, Nuremberg, Germany, pp. 1847-1850. [3] 'Proceedings of the First Action's General Meeting - Rome, Italy, July 2013' 1st edition, COST Action TU1208, Aracne, L. Pajewski and A. Benedetto, Eds., Rome, Italy, July 2013, ISBN 978-88-548-6191-6, available online at www.GPRadar.eu. [4] 'Booklet of Participants and Institutions,' 1st edition, COST Action TU1208, Aracne, L. Pajewski and A. Benedetto, Eds., Rome, Italy, July 2013, ISBN 978-88-548-6192-3, available online at www.GPRadar.eu. [5] 'Proceedings of the 2014 Working Group Progress Meeting - Nantes, France, February 2014,' COST Action TU1208, Aracne, L. Pajewski and X. Derobert, Eds., Rome, Italy, May 2014, ISBN 978-88-548-7223-3, available online at www.GPRadar.eu. [6] 'Proceedings of the Second Action's General Meeting - Vienna, Austria, April-May 2014,' COST Action TU1208, Aracne, L. Pajewski and A. Benedetto, Eds., Rome, Italy, 2014, ISBN 978-88-548-7224-0. [7] 'Short Term Scientific Missions and Training Schools - Year 1,' COST Action TU1208, Aracne, L. Pajewski and M. Marciniak, Eds., Rome, Italy, 2014, ISBN 978-88-548-7225-7. [8] 'Civil Engineering Applications of Ground Penetrating Radar,' A. Benedetto and L. Pajewski Eds., Springer, July 2015, ISBN 978

  14. Research on effect of rough surface on FMCW laser radar range accuracy

    Science.gov (United States)

    Tao, Huirong

    2018-03-01

    The non-cooperative targets large scale measurement system based on frequency-modulated continuous-wave (FMCW) laser detection and ranging technology has broad application prospects. It is easy to automate measurement without cooperative targets. However, the complexity and diversity of the surface characteristics of the measured surface directly affects the measurement accuracy. First, the theoretical analysis of range accuracy for a FMCW laser radar was studied, the relationship between surface reflectivity and accuracy was obtained. Then, to verify the effect of surface reflectance for ranging accuracy, a standard tool ball and three standard roughness samples were measured within 7 m to 24 m. The uncertainty of each target was obtained. The results show that the measurement accuracy is found to increase as the surface reflectivity gets larger. Good agreements were obtained between theoretical analysis and measurements from rough surfaces. Otherwise, when the laser spot diameter is smaller than the surface correlation length, a multi-point averaged measurement can reduce the measurement uncertainty. The experimental results show that this method is feasible.

  15. Attenuation-difference radar tomography: results of a multiple-plane experiment at the U.S. Geological Survey Fractured-Rock Research Site, Mirror Lake, New Hampshire

    Science.gov (United States)

    Lane, J.W.; Day-Lewis, F. D.; Harris, J.M.; Haeni, F.P.; Gorelick, S.M.

    2000-01-01

    Attenuation-difference, borehole-radar tomography was used to monitor a series of sodium chloride tracer injection tests conducted within the FSE, wellfield at the U.S. Geological Survey Fractured-Rock Hydrology Research Site in Grafton County, New Hampshire, USA. Borehole-radar tomography surveys were conducted using the sequential-scanning and injection method in three boreholes that form a triangular prism of adjoining tomographic image planes. Results indicate that time-lapse tomography methods provide high-resolution images of tracer distribution in permeable zones.

  16. Research and development of environment measuring laser radar. 6. Follow-up; Kankyo keisokuyo laser radar no kenkyu kaihatsu. 6. Follow up

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    In an effort to extend cooperation for reducing pollution in urban areas in the Asia-Pacific Region, a laser radar system was constructed in the city of Djakarta, Indonesia, in 1996, and a follow-up started in fiscal 1997. The aim is to collect information necessary for atmospheric environment improvement through observing pollutant distribution and movement in the upper atmospheric layers over the city. Mie-scattering lidar (laser infrared radar) observation has uninterruptedly been on since the summer of 1997, the system collecting data about Djakarta's atmospheric boundary structure throughout the year. The data indicate great changes in the atmospheric boundary structure between the dry and rainy seasons. The result of intensified observation conducted in the dry season shows that the altitude that the mixed layer reaches in the inland region is higher in the daytime and lower in the nighttime. It is necessary to compare the result with atmospheric pollution data collected on the ground surface and determine the relationship between the behavior of pollutants and the circulation of land-and-sea breeze. The data of September, 1997, reveal an aerosol layer at altitudes of 2km and higher, and this is attributed to forest fires. The result of intensified observation conducted in the dry season of 1998 is also stated. (NEDO)

  17. Recommendation on Transition from Primary/Secondary Radar to Secondary- Only Radar Capability

    Science.gov (United States)

    1994-10-01

    Radar Beacon Performance Monitor RCIU Remote Control Interface Unit RCL Remote Communications Link R E&D Research, Engineering and Development RML Radar...rate. 3.1.2.5 Maintenance The current LRRs have limited remote maintenance monitoring (RMM) capabilities via the Remote Control Interface Unit ( RCIU ...1, -2 and FPS-20 radars required an upgrade of some of the radar subsystems, namely the RCIU to respond as an RMS and the CD to interface with radar

  18. The use of Ground Penetrating Radar in coastal research, archeaological investigations, lake studies, peat layer measurments and applied research in Estonia

    Science.gov (United States)

    Vilumaa, Kadri; Tõnisson, Hannes; Orviku, Kaarel

    2014-05-01

    Ground Penetrating Radar (GPR) is mainly used for scientific research in coastal geology in the Institute of Ecology at Tallinn University. We currently use SIR-3000 radar with 100, 270 , 300 and 500 MHz antennae. Our main targets have been detecting the thickness of soil and sand layers and finding out the layers in coastal sediments which reflect extreme storm events. Our GPR studies in various settings have suggested that the internal structures of the ridge-dune complexes are dominated by numerous layers dipping in various directions. Such information helps us to reconstruct and understand prevailing processes during their formation (e.g. seaward dipping lamination in coastal ridge-dune complexes indicating cross-shore and wave-induced transport of the sediments). Currently, we are trying to elaborate methodology for distinguishing the differences between aeolian and wave transported sediments by using GPR. However, paludified landscapes (often covered by water), very rough surface (numerous bushes and soft surface), moderate micro topography has slowed this process significantly. Moreover, we have been able to use GPR during the winter period (applied on ice or snow) and compare the quality of our results with the measurements taken during the summer period. We have found that smooth surface (in winter) helps detecting very strong signal differences (border between different sediment types - sand, peat, silt, etc.) but reduces the quality of the signal to the level where the detection of sedimentation patterns within one material (e.g. tilted layers in sand) is difficult. We have carried out several other science-related studies using GPR. These studies include determining the thickness of peat layer in bogs (to calculate the volume of accumulated peat or to find most suitable locations for coring), measuring the thickness of mud and gyttja layer in lakes (to find most suitable locations for coring, reconstructing initial water level of the lake or calculating

  19. Range performance calculations using the NVEOL-Georgia Tech Research Institute 0.1- to 100-GHz radar performance model

    Science.gov (United States)

    Rodak, S. P.; Thomas, N. I.

    1983-05-01

    A computer model that can be used to calculate radar range performance at any frequency in the 0.1-to 100-GHz electromagnetic spectrum is described. These different numerical examples are used to demonstrate how to use the radar range performance model. Input/output documentation are included for each case that was run on the MERADCOM CDC 6600 computer at Fort Belvoir, Virginia.

  20. Research and development cooperation project on environmental measurement using laser radar in fiscal 1994 (environmental network); Kankyo keisokuyo laser radar no kaihatsu ni kansuru kenkyu kyoryoku (kankyo network)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    Under the R and D of a laser radar for environmental measurement which are conducted in cooperation with Indonesia, the paper reported the R and D of the environmental network in fiscal 1994. Four field surveys were made, and the following were conducted: proposal of a technical system, adjustment of the Asian environmental information network with BPPT and LIPI which are organs on the Indonesian side, installation of/technical discussion on network equipment, etc. There is IPTEKNET as a plan of a nationwide network of the scientific technology information service in Indonesia. The analytical design phase of this system converged in 1992, and the predicted investment amount in the coming five years is expected to be 6.7 million US dollars. As the future Asian environmental information network work, planned are connection between BPPT and Tokyo CC and connection at BPPT between the Asian environmental information network and IPTEKNET. Network managers at sites are very skillful, and therefore, the thorough cooperative work is anticipated. 24 figs.

  1. Ground penetrating radar measurements at the ONKALO research tunnel and eastern part of the Olkiluoto investigation area at July 2006

    International Nuclear Information System (INIS)

    Sipola, V.; Tarvainen, A.-M.

    2007-04-01

    Ground Penetrating Radar (GPR) measurements were carried out at ONKALO research site in summer 2006. Measurements included 400 metres of measurements inside ONKALO access tunnel and about 1800 metres of measurements on the ground, at the eastern parts of Olkiluoto investigation area. The purpose of the measurements done inside the access tunnel was to investigate, whether it would be possible to locate deformation structures or long fractures in the rock mass below the tunnel. The purpose of the measurements made on top of the ground was to investigate, whether it would be possible to locate glacio-isostatic faults from the soils. A secondary target was to try and locate the rock surface. The chosen part of ONKALO tunnel was measured using five different frequencies, which enabled comparing the results to each other. It also enabled getting a higher resolution picture of the top rock, than what would have been possible using only one low-frequency antenna. The on-the-ground measurements were measured using only one frequency. (orig.)

  2. Radar geomorphology of coastal and wetland environments

    Science.gov (United States)

    Lewis, A. J.; Macdonald, H. C.

    1973-01-01

    Details regarding the collection of radar imagery over the past ten years are considered together with the geomorphic, geologic, and hydrologic data which have been extracted from radar imagery. Recent investigations were conducted of the Louisiana swamp marsh and the Oregon coast. It was found that radar imagery is a useful tool to the scientist involved in wetland research.

  3. Weather Radar Stations

    Data.gov (United States)

    Department of Homeland Security — These data represent Next-Generation Radar (NEXRAD) and Terminal Doppler Weather Radar (TDWR) weather radar stations within the US. The NEXRAD radar stations are...

  4. Bistatic radar

    CERN Document Server

    Willis, Nick

    2004-01-01

    Annotation his book is a major extension of a chapter on bistatic radar written by the author for the Radar Handbook, 2nd edition, edited by Merrill Skolnik. It provides a history of bistatic systems that points out to potential designers the applications that have worked and the dead-ends not worth pursuing. The text reviews the basic concepts and definitions, and explains the mathematical development of relationships, such as geometry, Ovals of Cassini, dynamic range, isorange and isodoppler contours, target doppler, and clutter doppler spread.Key Features * All development and analysis are

  5. Research Progress of Space-Time Adaptive Detection for Airborne Radar

    Directory of Open Access Journals (Sweden)

    Wang Yong-liang

    2014-04-01

    Full Text Available Compared with Space-Time Adaptive Processing (STAP, Space-Time Adaptive Detection (STAD employs the data in the cell under test and those in the training to form reasonable detection statistics and consequently decides whether the target exists or not. The STAD has concise processing procedure and flexible design. Furthermore, the detection statistics usually possess the Constant False Alarm Rate (CFAR property, and hence it needs no additional CFAR processing. More importantly, the STAD usually exhibits improved detection performance than that of the conventional processing, which first suppresses the clutter then adopts other detection strategy. In this paper, we first summarize the key strongpoint of the STAD, then make a classification for the STAD, and finally give some future research tracks.

  6. COST Action TU1208 "Civil Engineering Applications of Ground Penetrating Radar": ongoing research activities and third-year results

    Science.gov (United States)

    Pajewski, Lara; Benedetto, Andrea; Loizos, Andreas; Tosti, Fabio

    2016-04-01

    This work aims at disseminating the ongoing research activities and third-year results of the COST (European COoperation in Science and Technology) Action TU1208 "Civil Engineering Applications of Ground Penetrating Radar." About 350 experts are participating to the Action, from 28 COST Countries (Austria, Belgium, Croatia, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Ireland, Italy, Latvia, Malta, Macedonia, The Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey, United Kingdom), and from Albania, Armenia, Australia, Colombia, Egypt, Hong Kong, Jordan, Israel, Philippines, Russia, Rwanda, Ukraine, and United States of America. In September 2014, TU1208 has been recognised among the running Actions as "COST Success Story" ("The Cities of Tomorrow: The Challenges of Horizon 2020," September 17-19, 2014, Torino, IT - A COST strategic workshop on the development and needs of the European cities). The principal goal of the COST Action TU1208 is to exchange and increase scientific-technical knowledge and experience of GPR techniques in civil engineering, whilst simultaneously promoting throughout Europe the effective use of this safe and non-destructive technique in the monitoring of infrastructures and structures. Moreover, the Action is oriented to the following specific objectives and expected deliverables: (i) coordinating European scientists to highlight problems, merits and limits of current GPR systems; (ii) developing innovative protocols and guidelines, which will be published in a handbook and constitute a basis for European standards, for an effective GPR application in civil- engineering tasks; safety, economic and financial criteria will be integrated within the protocols; (iii) integrating competences for the improvement and merging of electromagnetic scattering techniques and of data- processing techniques; this will lead to a novel freeware tool for the localization of

  7. Simulation of a weather radar display for over-water airborne radar approaches

    Science.gov (United States)

    Clary, G. R.

    1983-01-01

    Airborne radar approach (ARA) concepts are being investigated as a part of NASA's Rotorcraft All-Weather Operations Research Program on advanced guidance and navigation methods. This research is being conducted using both piloted simulations and flight test evaluations. For the piloted simulations, a mathematical model of the airborne radar was developed for over-water ARAs to offshore platforms. This simulated flight scenario requires radar simulation of point targets, such as oil rigs and ships, distributed sea clutter, and transponder beacon replies. Radar theory, weather radar characteristics, and empirical data derived from in-flight radar photographs are combined to model a civil weather/mapping radar typical of those used in offshore rotorcraft operations. The resulting radar simulation is realistic and provides the needed simulation capability for ongoing ARA research.

  8. RADAR PPI Scope Overlay

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — RADAR PPI Scope Overlays are used to position a RADAR image over a station at the correct resolution. The archive maintains several different RADAR resolution types,...

  9. The NASA Polarimetric Radar (NPOL)

    Science.gov (United States)

    Petersen, Walter A.; Wolff, David B.

    2013-01-01

    Characteristics of the NASA NPOL S-band dual-polarimetric radar are presented including its operating characteristics, field configuration, scanning capabilities and calibration approaches. Examples of precipitation science data collections conducted using various scan types, and associated products, are presented for different convective system types and previous field campaign deployments. Finally, the NASA NPOL radar location is depicted in its home base configuration within the greater Wallops Flight Facility precipitation research array supporting NASA Global Precipitation Measurement Mission ground validation.

  10. Advances in bistatic radar

    CERN Document Server

    Willis, Nick

    2007-01-01

    Advances in Bistatic Radar updates and extends bistatic and multistatic radar developments since publication of Willis' Bistatic Radar in 1991. New and recently declassified military applications are documented. Civil applications are detailed including commercial and scientific systems. Leading radar engineers provide expertise to each of these applications. Advances in Bistatic Radar consists of two major sections: Bistatic/Multistatic Radar Systems and Bistatic Clutter and Signal Processing. Starting with a history update, the first section documents the early and now declassified military

  11. MAJOR SOURCE OF SIDE-LOOKING AIRBORNE RADAR IMAGERY FOR RESEARCH AND EXPLORATION: THE U. S. GEOLOGICAL SURVEY.

    Science.gov (United States)

    Kover, Allan N.; Jones, John Edwin; ,

    1985-01-01

    The US Geological Survey (USGS) instituted a program in 1980 to acquire side-looking airbore radar (SLAR) data and make these data readily available to the public in a mosaic format comparable to the USGS 1:250,000-scale topographic map series. The SLAR data are also available as strip images at an acquisition scale of 1:250,000 or 1:400,000 (depending on the acquisition system), as a variety of print products and indexes, and in a limited amount in digital form on computer compatible tapes. Three different commercial X-band (3-cm) systems were used to acquire the imagery for producing the mosaics.

  12. Penn State Radar Systems: Implementation and Observations

    Science.gov (United States)

    Urbina, J. V.; Seal, R.; Sorbello, R.; Kuyeng, K.; Dyrud, L. P.

    2014-12-01

    Software Defined Radio/Radar (SDR) platforms have become increasingly popular as researchers, hobbyists, and military seek more efficient and cost-effective means for radar construction and operation. SDR platforms, by definition, utilize a software-based interface for configuration in contrast to traditional, hard-wired platforms. In an effort to provide new and improved radar sensing capabilities, Penn State has been developing advanced instruments and technologies for future radars, with primary objectives of making such instruments more capable, portable, and more cost effective. This paper will describe the design and implementation of two low-cost radar systems and their deployment in ionospheric research at both low and mid-latitudes. One radar has been installed near Penn State campus, University Park, Pennsylvania (77.97°W, 40.70°N), to make continuous meteor observations and mid-latitude plasma irregularities. The second radar is being installed in Huancayo (12.05°S, -75.33°E), Peru, which is capable of detecting E and F region plasma irregularities as well as meteor reflections. In this paper, we examine and compare the diurnal and seasonal variability of specular, non- specular, and head-echoes collected with these two new radar systems and discuss sampling biases of each meteor observation technique. We report our current efforts to validate and calibrate these radar systems with other VHF radars such as Jicamarca and SOUSY. We also present the general characteristics of continuous measurements of E-region and F-region coherent echoes using these modern radar systems and compare them with coherent radar events observed at other geographic mid-latitude radar stations.

  13. Pedestrian recognition using automotive radar sensors

    OpenAIRE

    A. Bartsch; F. Fitzek; R. H. Rasshofer

    2012-01-01

    The application of modern series production automotive radar sensors to pedestrian recognition is an important topic in research on future driver assistance systems. The aim of this paper is to understand the potential and limits of such sensors in pedestrian recognition. This knowledge could be used to develop next generation radar sensors with improved pedestrian recognition capabilities. A new raw radar data signal processing algorithm is proposed that allows deep insight...

  14. Radar and Lidar Radar DEM

    Science.gov (United States)

    Liskovich, Diana; Simard, Marc

    2011-01-01

    Using radar and lidar data, the aim is to improve 3D rendering of terrain, including digital elevation models (DEM) and estimates of vegetation height and biomass in a variety of forest types and terrains. The 3D mapping of vegetation structure and the analysis are useful to determine the role of forest in climate change (carbon cycle), in providing habitat and as a provider of socio-economic services. This in turn will lead to potential for development of more effective land-use management. The first part of the project was to characterize the Shuttle Radar Topography Mission DEM error with respect to ICESat/GLAS point estimates of elevation. We investigated potential trends with latitude, canopy height, signal to noise ratio (SNR), number of LiDAR waveform peaks, and maximum peak width. Scatter plots were produced for each variable and were fitted with 1st and 2nd degree polynomials. Higher order trends were visually inspected through filtering with a mean and median filter. We also assessed trends in the DEM error variance. Finally, a map showing how DEM error was geographically distributed globally was created.

  15. Radar absorbing properties of carbon nanotubes/polymer ...

    Indian Academy of Sciences (India)

    This research is devoted to the study of radar absorbing properties of the composites, based on the epoxy binder and ... Radar absorbing materials; carbon nanotubes; nanocomposites; reflection loss. 1. ..... So, for example, the papers of [3–5 ...

  16. Radar and ARPA manual

    CERN Document Server

    Bole, A G

    2013-01-01

    Radar and ARPA Manual focuses on the theoretical and practical aspects of electronic navigation. The manual first discusses basic radar principles, including principles of range and bearing measurements and picture orientation and presentation. The text then looks at the operational principles of radar systems. Function of units; aerial, receiver, and display principles; transmitter principles; and sitting of units on board ships are discussed. The book also describes target detection, Automatic Radar Plotting Aids (ARPA), and operational controls of radar systems, and then discusses radar plo

  17. Weather radar rainfall data in urban hydrology

    DEFF Research Database (Denmark)

    Thorndahl, Søren; Einfalt, Thomas; Willems, Patrick

    2017-01-01

    estimation, radar data adjustment and data quality, and (3) nowcasting of radar rainfall and real-time applications. Based on these three fields of research, the paper provides recommendations based on an updated overview of shortcomings, gains, and novel developments in relation to urban hydrological...... applications. The paper also reviews how the focus in urban hydrology research has shifted over the last decade to fields such as climate change impacts, resilience of urban areas to hydrological extremes, and online prediction/warning systems. It is discussed how radar rainfall data can add value......Application of weather radar data in urban hydrological applications has evolved significantly during the past decade as an alternative to traditional rainfall observations with rain gauges. Advances in radar hardware, data processing, numerical models, and emerging fields within urban hydrology...

  18. Radar Weather Observation

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Radar Weather Observation is a set of archived historical manuscripts stored on microfiche. The primary source of these radar weather observations manuscript records...

  19. ISTEF Laser Radar Program

    National Research Council Canada - National Science Library

    Stryjewski, John

    1998-01-01

    The BMDO Innovative Science and Technology Experimentation Facility (BMDO/ISTEF) laser radar program is engaged in an ongoing program to develop and demonstrate advanced laser radar concepts for Ballistic Missile Defense (BMD...

  20. Weather Radar Impact Zones

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent an inventory of the national impacts of wind turbine interference with NEXRAD radar stations. This inventory was developed by the NOAA Radar...

  1. Radar signal processing and its applications

    CERN Document Server

    Hummel, Robert; Stoica, Petre; Zelnio, Edmund

    2003-01-01

    Radar Signal Processing and Its Applications brings together in one place important contributions and up-to-date research results in this fast-moving area. In twelve selected chapters, it describes the latest advances in architectures, design methods, and applications of radar signal processing. The contributors to this work were selected from the leading researchers and practitioners in the field. This work, originally published as Volume 14, Numbers 1-3 of the journal, Multidimensional Systems and Signal Processing, will be valuable to anyone working or researching in the field of radar signal processing. It serves as an excellent reference, providing insight into some of the most challenging issues being examined today.

  2. Principles of modern radar systems

    CERN Document Server

    Carpentier, Michel H

    1988-01-01

    Introduction to random functions ; signal and noise : the ideal receiver ; performance of radar systems equipped with ideal receivers ; analysis of the operating principles of some types of radar ; behavior of real targets, fluctuation of targets ; angle measurement using radar ; data processing of radar information, radar coverage ; applications to electronic scanning antennas to radar ; introduction to Hilbert spaces.

  3. Characterization of adolescent prescription drug abuse and misuse using the Researched Abuse Diversion and Addiction-related Surveillance (RADARS(®)) System.

    Science.gov (United States)

    Zosel, Amy; Bartelson, Becki Bucher; Bailey, Elise; Lowenstein, Steven; Dart, Rick

    2013-02-01

    To describe the characteristics and health effects of adolescent (age 13-19 years) prescription drug abuse and misuse using the Researched Abuse Diversion and Addiction-Related Surveillance (RADARS(®)) System. Secondary analysis of data collected from RADARS System participating poison centers was performed. Data for all intentional exposures from 2007 through 2009 were used to describe adolescent prescription opioid (oxycodone, fentanyl, hydrocodone, hydromorphone, morphine, methadone, buprenorphine, and tramadol) and stimulant (methylphenidate and amphetamines) exposures. A total of 16,209 intentional adolescent exposures to prescription drugs were identified, 68% to opioids and 32% to stimulants. The mean age was 16.6 years (SD ± 1.7 years). Slightly more than half (52.4%) of drug mentions involved females. The five most frequently misused or abused drugs were hydrocodone (32%), amphetamines (18%), oxycodone (15%), methylphenidate (14%), and tramadol (11%). Of all exposures, 38% were classified as suspected suicidal. Of adolescents who intentionally exposed themselves to prescription drugs, 30% were treated in a health care facility, 2,792 of whom were admitted to the hospital, including 1,293 to the intensive care unit. A total of 17.2% of intentional exposures were associated with no effect, 38.9% minor effects, 23.3% moderate effects, 3.6% major effects, and 0.1% were associated with death. Oxycodone and methadone were associated with the most deaths. No deaths were associated with exposures to stimulants. Prescription drug misuse and abuse poses an important health problem and results in thousands of hospitalizations of adolescents per year. Further work is needed to develop focused interventions and educational programs to prevent prescription drug abuse and misuse by adolescents. Copyright © 2013 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

  4. Software Radar Technology

    Directory of Open Access Journals (Sweden)

    Tang Jun

    2015-08-01

    Full Text Available In this paper, the definition and the key features of Software Radar, which is a new concept, are proposed and discussed. We consider the development of modern radar system technology to be divided into three stages: Digital Radar, Software radar and Intelligent Radar, and the second stage is just commencing now. A Software Radar system should be a combination of various modern digital modular components conformed to certain software and hardware standards. Moreover, a software radar system with an open system architecture supporting to decouple application software and low level hardware would be easy to adopt "user requirements-oriented" developing methodology instead of traditional "specific function-oriented" developing methodology. Compared with traditional Digital Radar, Software Radar system can be easily reconfigured and scaled up or down to adapt to the changes of requirements and technologies. A demonstration Software Radar signal processing system, RadarLab 2.0, which has been developed by Tsinghua University, is introduced in this paper and the suggestions for the future development of Software Radar in China are also given in the conclusion.

  5. Weather radar rainfall data in urban hydrology

    DEFF Research Database (Denmark)

    Thorndahl, Søren; Einfalt, Thomas; Willems, Patrick

    2017-01-01

    Application of weather radar data in urban hydrological applications has evolved significantly during the past decade as an alternative to traditional rainfall observations with rain gauges. Advances in radar hardware, data processing, numerical models, and emerging fields within urban hydrology...... necessitate an updated review of the state of the art in such radar rainfall data and applications. Three key areas with significant advances over the past decade have been identified: (1) temporal and spatial resolution of rainfall data required for different types of hydrological applications, (2) rainfall...... estimation, radar data adjustment and data quality, and (3) nowcasting of radar rainfall and real-time applications. Based on these three fields of research, the paper provides recommendations based on an updated overview of shortcomings, gains, and novel developments in relation to urban hydrological...

  6. Understanding radar systems

    CERN Document Server

    Kingsley, Simon

    1999-01-01

    What is radar? What systems are currently in use? How do they work? This book provides engineers and scientists with answers to these critical questions, focusing on actual radar systems in use today. It is a perfect resource for those just entering the field, or as a quick refresher for experienced practitioners. The book leads readers through the specialized language and calculations that comprise the complex world of radar engineering as seen in dozens of state-of-the-art radar systems. An easy to read, wide ranging guide to the world of modern radar systems.

  7. Pulse Doppler radar

    CERN Document Server

    Alabaster, Clive

    2012-01-01

    This book is a practitioner's guide to all aspects of pulse Doppler radar. It concentrates on airborne military radar systems since they are the most used, most complex, and most interesting of the pulse Doppler radars; however, ground-based and non-military systems are also included. It covers the fundamental science, signal processing, hardware issues, systems design and case studies of typical systems. It will be a useful resource for engineers of all types (hardware, software and systems), academics, post-graduate students, scientists in radar and radar electronic warfare sectors and milit

  8. Airborne Radar Search for Diesel Submarines (ARSDS)

    National Research Council Canada - National Science Library

    Pilnick, Steven E; Landa, Jose

    2005-01-01

    .... In this research, a detection rate model is developed to analyze the effectiveness of an airborne radar search for a diesel submarine assumed to be intermittently operating with periscopes or masts...

  9. Airborne Radar Search for Diesel Submarines

    National Research Council Canada - National Science Library

    Pilnick, Steven E; Landa, Jose

    2005-01-01

    .... In this research, a detection rate model is developed to analyze the effectiveness of airborne radar search for a diesel submarine assumed to be intermittently operating with periscopes or masts...

  10. 100 years of radar

    CERN Document Server

    Galati, Gaspare

    2016-01-01

    This book offers fascinating insights into the key technical and scientific developments in the history of radar, from the first patent, taken out by Hülsmeyer in 1904, through to the present day. Landmark events are highlighted and fascinating insights provided into the exceptional people who made possible the progress in the field, including the scientists and technologists who worked independently and under strict secrecy in various countries across the world in the 1930s and the big businessmen who played an important role after World War II. The book encourages multiple levels of reading. The author is a leading radar researcher who is ideally placed to offer a technical/scientific perspective as well as a historical one. He has taken care to structure and write the book in such a way as to appeal to both non-specialists and experts. The book is not sponsored by any company or body, either formally or informally, and is therefore entirely unbiased. The text is enriched by approximately three hundred ima...

  11. New Vacuum Electronic Devices for Radar

    Directory of Open Access Journals (Sweden)

    Hu Yinfu

    2016-08-01

    Full Text Available Vacuum Electronic Devices (VEDs which are considered as the heart of a radar system, play an important role in their development. VEDs and radar systems supplement and promote each other. Some new trends in VEDs have been observed with advancements in the simulation tools for designing VEDs, new materials, new fabrication techniques. Recently, the performance of VEDs has greatly improved. In addition, new devices have been invented, which have laid the foundation for the developments of radar detection technology. This study introduces the recent development trends and research results of VEDs from microwave and millimeter wave devices and power modules, integrated VEDs, terahertz VEDs, and high power VEDs.

  12. Ground penetrating radar for fracture mapping in underground hazardous waste disposal sites: A case study from an underground research tunnel, South Korea

    Science.gov (United States)

    Baek, Seung-Ho; Kim, Seung-Sep; Kwon, Jang-Soon; Um, Evan Schankee

    2017-06-01

    Secure disposal or storage of nuclear waste within stable geologic environments hinges on the effectiveness of artificial and natural radiation barriers. Fractures in the bedrock are viewed as the most likely passage for the transport of radioactive waste away from a disposal site. We utilize ground penetrating radar (GPR) to map fractures in the tunnel walls of an underground research tunnel at the Korea Atomic Energy Research Institute (KAERI). GPR experiments within the KAERI Underground Research Tunnel (KURT) were carried out by using 200 MHz, 500 MHz, and 1000 MHz antennas. By using the high-frequency antennas, we were able to identify small-scale fractures, which were previously unidentified during the tunnel excavation process. Then, through 3-D visualization of the grid survey data, we reconstructed the spatial distribution and interconnectivity of the multi-scale fractures within the wall. We found that a multi-frequency GPR approach provided more details of the complex fracture network, including deep structures. Furthermore, temporal changes in reflection polarity between the GPR surveys enabled us to infer the hydraulic characteristics of the discrete fracture network developed behind the surveyed wall. We hypothesized that the fractures exhibiting polarity change may be due to a combination of air-filled and mineralogical boundaries. Simulated GPR scans for the considered case were consistent with the observed GPR data. If our assumption is correct, the groundwater flow into these near-surface fractures may form the water-filled fractures along the existing air-filled ones and hence cause the changes in reflection polarity over the given time interval (i.e., 7 days). Our results show that the GPR survey is an efficient tool to determine fractures at various scales. Time-lapse GPR data may be essential to characterize the hydraulic behavior of discrete fracture networks in underground disposal facilities.

  13. Under the Radar

    CERN Document Server

    Goss, WM

    2010-01-01

    This is the biography of Ruby Payne-Scott (1912 to 1981). As the first female radio astronomer (and one of the first people in the world to consider radio astronomy), she made classic contributions to solar radio physics. She also played a major role in the design of the Australian government's Council for Scientific and Industrial Research radars, which were in turn of vital importance in the Southwest Pacific Theatre in World War II and were used by Australian, US and New Zealand personnel. From a sociological perspective, her career also offers many examples of the perils of being a female academic in the first half of the 20th century. Written in an engaging style and complemented by many historical photographs this book gives a fascinating insight into the beginning of radio astronomy and the role of a pioneering woman in astronomy.

  14. Phased-array radar design application of radar fundamentals

    CERN Document Server

    Jeffrey, Thomas

    2009-01-01

    Phased-Array Radar Design is a text-reference designed for electrical engineering graduate students in colleges and universities as well as for corporate in-house training programs for radar design engineers, especially systems engineers and analysts who would like to gain hands-on, practical knowledge and skills in radar design fundamentals, advanced radar concepts, trade-offs for radar design and radar performance analysis.

  15. Radar Signature Calculation Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: The calculation, analysis, and visualization of the spatially extended radar signatures of complex objects such as ships in a sea multipath environment and...

  16. Performance Prediction of Constrained Waveform Design for Adaptive Radar

    Science.gov (United States)

    2016-11-01

    the famous Woodward quote, having a ubiquitous feeling for all radar waveform design (and performance prediction) researchers , that is found at the end...discuss research that develops performance prediction models to quantify the impact on SINR when an amplitude constraint is placed on a radar waveform...optimize the radar perfor- mance for the particular scenario and tasks. There have also been several survey papers on various topics in waveform design for

  17. Survey of Ultra-wideband Radar

    Science.gov (United States)

    Mokole, Eric L.; Hansen, Pete

    The development of UWB radar over the last four decades is very briefly summarized. A discussion of the meaning of UWB is followed by a short history of UWB radar developments and discussions of key supporting technologies and current UWB radars. Selected UWB radars and the associated applications are highlighted. Applications include detecting and imaging buried mines, detecting and mapping underground utilities, detecting and imaging objects obscured by foliage, through-wall detection in urban areas, short-range detection of suicide bombs, and the characterization of the impulse responses of various artificial and naturally occurring scattering objects. In particular, the Naval Research Laboratory's experimental, low-power, dual-polarized, short-pulse, ultra-high resolution radar is used to discuss applications and issues of UWB radar. Some crucial issues that are problematic to UWB radar are spectral availability, electromagnetic interference and compatibility, difficulties with waveform control/shaping, hardware limitations in the transmission chain, and the unreliability of high-power sources for sustained use above 2 GHz.

  18. Pedestrian recognition using automotive radar sensors

    Science.gov (United States)

    Bartsch, A.; Fitzek, F.; Rasshofer, R. H.

    2012-09-01

    The application of modern series production automotive radar sensors to pedestrian recognition is an important topic in research on future driver assistance systems. The aim of this paper is to understand the potential and limits of such sensors in pedestrian recognition. This knowledge could be used to develop next generation radar sensors with improved pedestrian recognition capabilities. A new raw radar data signal processing algorithm is proposed that allows deep insights into the object classification process. The impact of raw radar data properties can be directly observed in every layer of the classification system by avoiding machine learning and tracking. This gives information on the limiting factors of raw radar data in terms of classification decision making. To accomplish the very challenging distinction between pedestrians and static objects, five significant and stable object features from the spatial distribution and Doppler information are found. Experimental results with data from a 77 GHz automotive radar sensor show that over 95% of pedestrians can be classified correctly under optimal conditions, which is compareable to modern machine learning systems. The impact of the pedestrian's direction of movement, occlusion, antenna beam elevation angle, linear vehicle movement, and other factors are investigated and discussed. The results show that under real life conditions, radar only based pedestrian recognition is limited due to insufficient Doppler frequency and spatial resolution as well as antenna side lobe effects.

  19. Radar Plan Position Indicator Scope

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Radar Plan Position Indicator Scope is the collection of weather radar imagery for the period prior to the beginning of the Next Generation Radar (NEXRAD) system...

  20. Low-Cost Mini Radar: Design Prototyping and Tests

    Directory of Open Access Journals (Sweden)

    Dario Tarchi

    2017-01-01

    Full Text Available Radar systems are largely employed for surveillance of wide and remote areas; the recent advent of drones gives the opportunity to exploit radar sensors on board of unmanned aerial platforms. Nevertheless, whereas drone radars are currently available for military applications, their employment in the civilian domain is still limited. The present research focuses on design, prototyping, and testing of an agile, low-cost, mini radar system, to be carried on board of Remotely Piloted Aircraft (RPAs or tethered aerostats. In particular, the paper faces the challenge to integrate the in-house developed radar sensor with a low-cost navigation board, which is used to estimate attitude and positioning data. In fact, a suitable synchronization between radar and navigation data is essential to properly reconstruct the radar picture whenever the platform is moving or the radar is scanning different azimuthal sectors. Preliminary results, relative to tests conducted in preoperational conditions, are provided and exploited to assert the suitable consistency of the obtained radar pictures. From the results, there is a high consistency between the radar images and the picture of the current environment emerges; finally, the comparison of radar images obtained in different scans shows the stability of the platform.

  1. Combined radar and telemetry system

    Energy Technology Data Exchange (ETDEWEB)

    Rodenbeck, Christopher T.; Young, Derek; Chou, Tina; Hsieh, Lung-Hwa; Conover, Kurt; Heintzleman, Richard

    2017-08-01

    A combined radar and telemetry system is described. The combined radar and telemetry system includes a processing unit that executes instructions, where the instructions define a radar waveform and a telemetry waveform. The processor outputs a digital baseband signal based upon the instructions, where the digital baseband signal is based upon the radar waveform and the telemetry waveform. A radar and telemetry circuit transmits, simultaneously, a radar signal and telemetry signal based upon the digital baseband signal.

  2. POLCAL - POLARIMETRIC RADAR CALIBRATION

    Science.gov (United States)

    Vanzyl, J.

    1994-01-01

    Calibration of polarimetric radar systems is a field of research in which great progress has been made over the last few years. POLCAL (Polarimetric Radar Calibration) is a software tool intended to assist in the calibration of Synthetic Aperture Radar (SAR) systems. In particular, POLCAL calibrates Stokes matrix format data produced as the standard product by the NASA/Jet Propulsion Laboratory (JPL) airborne imaging synthetic aperture radar (AIRSAR). POLCAL was designed to be used in conjunction with data collected by the NASA/JPL AIRSAR system. AIRSAR is a multifrequency (6 cm, 24 cm, and 68 cm wavelength), fully polarimetric SAR system which produces 12 x 12 km imagery at 10 m resolution. AIRSTAR was designed as a testbed for NASA's Spaceborne Imaging Radar program. While the images produced after 1991 are thought to be calibrated (phase calibrated, cross-talk removed, channel imbalance removed, and absolutely calibrated), POLCAL can and should still be used to check the accuracy of the calibration and to correct it if necessary. Version 4.0 of POLCAL is an upgrade of POLCAL version 2.0 released to AIRSAR investigators in June, 1990. New options in version 4.0 include automatic absolute calibration of 89/90 data, distributed target analysis, calibration of nearby scenes with calibration parameters from a scene with corner reflectors, altitude or roll angle corrections, and calibration of errors introduced by known topography. Many sources of error can lead to false conclusions about the nature of scatterers on the surface. Errors in the phase relationship between polarization channels result in incorrect synthesis of polarization states. Cross-talk, caused by imperfections in the radar antenna itself, can also lead to error. POLCAL reduces cross-talk and corrects phase calibration without the use of ground calibration equipment. Removing the antenna patterns during SAR processing also forms a very important part of the calibration of SAR data. Errors in the

  3. Aspects of Radar Polarimetry

    OpenAIRE

    LÜNEBURG, Ernst

    2002-01-01

    This contribution is a tutorial introduction to the phenomenological theory of radar polarimetry for the coherent scatter case emphasizing monostatic backscattering and forward scattering (transmission). Characteristic similarities and differences between radar polarimetry and optical polarimetry and the role of linear and antilinear operators (time-reversal) are pointed out and typical polarimetric invariants are identified.

  4. Java Radar Analysis Tool

    Science.gov (United States)

    Zaczek, Mariusz P.

    2005-01-01

    Java Radar Analysis Tool (JRAT) is a computer program for analyzing two-dimensional (2D) scatter plots derived from radar returns showing pieces of the disintegrating Space Shuttle Columbia. JRAT can also be applied to similar plots representing radar returns showing aviation accidents, and to scatter plots in general. The 2D scatter plots include overhead map views and side altitude views. The superposition of points in these views makes searching difficult. JRAT enables three-dimensional (3D) viewing: by use of a mouse and keyboard, the user can rotate to any desired viewing angle. The 3D view can include overlaid trajectories and search footprints to enhance situational awareness in searching for pieces. JRAT also enables playback: time-tagged radar-return data can be displayed in time order and an animated 3D model can be moved through the scene to show the locations of the Columbia (or other vehicle) at the times of the corresponding radar events. The combination of overlays and playback enables the user to correlate a radar return with a position of the vehicle to determine whether the return is valid. JRAT can optionally filter single radar returns, enabling the user to selectively hide or highlight a desired radar return.

  5. Determination of radar MTF

    Energy Technology Data Exchange (ETDEWEB)

    Chambers, D. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    The ultimate goal of the Current Meter Array (CMA) is to be able to compare the current patterns detected with the array with radar images of the water surface. The internal wave current patterns modulate the waves on the water surface giving a detectable modulation of the radar cross-section (RCS). The function relating the RCS modulations to the current patterns is the Modulation Transfer Function (MTF). By comparing radar images directly with co-located CMA measurements the MTF can be determined. In this talk radar images and CMA measurements from a recent experiment at Loch Linnhe, Scotland, will be used to make the first direct determination of MTF for an X and S band radar at low grazing angles. The technical problems associated with comparing radar images to CMA data will be explained and the solution method discussed. The results suggest the both current and strain rate contribute equally to the radar modulation for X band. For S band, the strain rate contributes more than the current. The magnitude of the MTF and the RCS modulations are consistent with previous estimates when the wind is blowing perpendicular to the radar look direction.

  6. Principles of modern radar radar applications

    CERN Document Server

    Scheer, James A

    2013-01-01

    Principles of Modern Radar: Radar Applications is the third of the three-volume seriesof what was originally designed to be accomplished in one volume. As the final volumeof the set, it finishes the original vision of a complete yet bounded reference for radartechnology. This volume describes fifteen different system applications or class ofapplications in more detail than can be found in Volumes I or II.As different as the applications described, there is a difference in how these topicsare treated by the authors. Whereas in Volumes I and II there is strict adherence tochapter format and leve

  7. A radar-echo model for Mars

    International Nuclear Information System (INIS)

    Thompson, T.W.; Moore, H.J.

    1990-01-01

    Researchers developed a radar-echo model for Mars based on 12.6 cm continuous wave radio transmissions backscattered from the planet. The model broadly matches the variations in depolarized and polarized total radar cross sections with longitude observed by Goldstone in 1986 along 7 degrees S. and yields echo spectra that are generally similiar to the observed spectra. Radar map units in the model include an extensive cratered uplands unit with weak depolarized echo cross sections, average thermal inertias, moderate normal refelectivities, and moderate rms slopes; the volcanic units of Tharsis, Elysium, and Amazonis regions with strong depolarized echo cross sections, low thermal inertia, low normal reflectivities, and large rms slopes; and the northern planes units with moderate to strong depolarized echo cross sections, moderate to very high thermal inertias, moderate to large normal reflectivities, and moderate rms slopes. The relevance of the model to the interpretation of radar echoes from Mars is discussed

  8. Physical working principles of medical radar.

    Science.gov (United States)

    Aardal, Øyvind; Paichard, Yoann; Brovoll, Sverre; Berger, Tor; Lande, Tor Sverre; Hamran, Svein-Erik

    2013-04-01

    There has been research interest in using radar for contactless measurements of the human heartbeat for several years. While many systems have been demonstrated, not much attention have been given to the actual physical causes of why this work. The consensus seems to be that the radar senses small body movements correlated with heartbeats, but whether only the movements of the body surface or reflections from internal organs are also monitored have not been answered definitely. There has recently been proposed another theory that blood perfusion in the skin could be the main reason radars are able to detect heartbeats. In this paper, an experimental approach is given to determine the physical causes. The measurement results show that it is the body surface reflections that dominate radar measurements of human heartbeats.

  9. Edad, cohortes o período. Desenredando las causas del desinterés político en España

    Directory of Open Access Journals (Sweden)

    Carolina Galais

    2012-01-01

    Full Text Available ¿En qué medida el escaso interés por la política de los españoles se debe al efecto de la edad, del período o de la pertenencia a una cohorte? Mientras que la edad no puede explicar la evolución de los niveles agregados de interés por la política a lo largo del tiempo, la sustitución generacional sí; aunque cabe determinar si su efecto aumentaría, reproduciría o empeoraría los actuales niveles interés político. Finalmente, cabe tener en cuenta el período, el único factor capaz de provocar cambios a corto plazo en esta actitud. El artículo también pretende arrojar algo de luz sobre los mecanismos por los cuales determinadas cohortes tendrían una mayor o menor propensión a interesarse por la política; y concluye que el grado de desarrollo social y económico que experimentaron mientras crecieron resulta crucial.

  10. Radar-to-Radar Interference Suppression for Distributed Radar Sensor Networks

    Directory of Open Access Journals (Sweden)

    Wen-Qin Wang

    2014-01-01

    Full Text Available Radar sensor networks, including bi- and multi-static radars, provide several operational advantages, like reduced vulnerability, good system flexibility and an increased radar cross-section. However, radar-to-radar interference suppression is a major problem in distributed radar sensor networks. In this paper, we present a cross-matched filtering-based radar-to-radar interference suppression algorithm. This algorithm first uses an iterative filtering algorithm to suppress the radar-to-radar interferences and, then, separately matched filtering for each radar. Besides the detailed algorithm derivation, extensive numerical simulation examples are performed with the down-chirp and up-chirp waveforms, partially overlapped or inverse chirp rate linearly frequency modulation (LFM waveforms and orthogonal frequency division multiplexing (ODFM chirp diverse waveforms. The effectiveness of the algorithm is verified by the simulation results.

  11. MWR-05XP Mobile Phased Array Weather Radar

    OpenAIRE

    2014-01-01

    The NPS/CIRPAS Weather Radar Project objective is to develop the technology for adding a parallel weather processor capability to tactical military radars and to develop an advanced scientific instrument for investigation of atmospheric phenomena and other various types of research. The payoff to the military will be the integration of current weather data into the tactical radar picture. The payoff to the science community will be the availability of an advanced instrument for inves...

  12. Raindrop Size Distribution in Different Climatic Regimes from Disdrometer and Dual-Polarized Radar Analysis.

    Science.gov (United States)

    Bringi, V. N.; Chandrasekar, V.; Hubbert, J.; Gorgucci, E.; Randeu, W. L.; Schoenhuber, M.

    2003-01-01

    The application of polarimetric radar data to the retrieval of raindrop size distribution parameters and rain rate in samples of convective and stratiform rain types is presented. Data from the Colorado State University (CSU), CHILL, NCAR S-band polarimetric (S-Pol), and NASA Kwajalein radars are analyzed for the statistics and functional relation of these parameters with rain rate. Surface drop size distribution measurements using two different disdrometers (2D video and RD-69) from a number of climatic regimes are analyzed and compared with the radar retrievals in a statistical and functional approach. The composite statistics based on disdrometer and radar retrievals suggest that, on average, the two parameters (generalized intercept and median volume diameter) for stratiform rain distributions lie on a straight line with negative slope, which appears to be consistent with variations in the microphysics of stratiform precipitation (melting of larger, dry snow particles versus smaller, rimed ice particles). In convective rain, `maritime-like' and `continental-like' clusters could be identified in the same two-parameter space that are consistent with the different multiplicative coefficients in the Z = aR1.5 relations quoted in the literature for maritime and continental regimes.

  13. To See the Unseen: A History of Planetary Radar Astronomy

    Science.gov (United States)

    Butrica, Andrew J.

    1996-01-01

    This book relates the history of planetary radar astronomy from its origins in radar to the present day and secondarily to bring to light that history as a case of 'Big Equipment but not Big Science'. Chapter One sketches the emergence of radar astronomy as an ongoing scientific activity at Jodrell Bank, where radar research revealed that meteors were part of the solar system. The chief Big Science driving early radar astronomy experiments was ionospheric research. Chapter Two links the Cold War and the Space Race to the first radar experiments attempted on planetary targets, while recounting the initial achievements of planetary radar, namely, the refinement of the astronomical unit and the rotational rate and direction of Venus. Chapter Three discusses early attempts to organize radar astronomy and the efforts at MIT's Lincoln Laboratory, in conjunction with Harvard radio astronomers, to acquire antenna time unfettered by military priorities. Here, the chief Big Science influencing the development of planetary radar astronomy was radio astronomy. Chapter Four spotlights the evolution of planetary radar astronomy at the Jet Propulsion Laboratory, a NASA facility, at Cornell University's Arecibo Observatory, and at Jodrell Bank. A congeries of funding from the military, the National Science Foundation, and finally NASA marked that evolution, which culminated in planetary radar astronomy finding a single Big Science patron, NASA. Chapter Five analyzes planetary radar astronomy as a science using the theoretical framework provided by philosopher of science Thomas Kuhn. Chapter Six explores the shift in planetary radar astronomy beginning in the 1970s that resulted from its financial and institutional relationship with NASA Big Science. Chapter Seven addresses the Magellan mission and its relation to the evolution of planetary radar astronomy from a ground-based to a space-based activity. Chapters Eight and Nine discuss the research carried out at ground

  14. Radar and electronic navigation

    CERN Document Server

    Sonnenberg, G J

    2013-01-01

    Radar and Electronic Navigation, Sixth Edition discusses radar in marine navigation, underwater navigational aids, direction finding, the Decca navigator system, and the Omega system. The book also describes the Loran system for position fixing, the navy navigation satellite system, and the global positioning system (GPS). It reviews the principles, operation, presentations, specifications, and uses of radar. It also describes GPS, a real time position-fixing system in three dimensions (longitude, latitude, altitude), plus velocity information with Universal Time Coordinated (UTC). It is accur

  15. Wind farm radar study

    International Nuclear Information System (INIS)

    Davies, N.G.

    1995-01-01

    This report examines the possible degradations of radar performance that may be caused by the presence of a wind turbine generator within the radar coverage area. A brief literature survey reviews the previously published work, which is mainly concerned with degradation of broadcast TV reception. Estimates are made of wind turbine generator scattering cross-sections, and of the time and Doppler characteristics of the echo signals from representative wind turbine generator. The general characteristics of radar detection and tracking methods are described, and the behaviour of such systems in the presence of strong returns from a wind turbine generator (or an array of them) is discussed. (author)

  16. Radar observations of Mercury

    International Nuclear Information System (INIS)

    Harmon, J.K.; Campbell, D.B.

    1988-01-01

    Some of the radar altimetry profiles of Mercury obtained on the basis of data from the Arecibo Observatory are presented. In these measurements, the delay-Doppler method was used to measure altitudes along the Doppler equator, rather than to map radar reflectivity. The profiles, derived from observations made over a 6-yr period, provide extensive coverage over a restricted equatorial band and permit the identification of radar signatures for features as small as 50-km diameter craters and 1-km-high arcuate scarps. The data allowed identification of large-scale topographic features such as smooth plains subsidence zones and major highland regions

  17. Radar cross section

    CERN Document Server

    Knott, Gene; Tuley, Michael

    2004-01-01

    This is the second edition of the first and foremost book on this subject for self-study, training, and course work. Radar cross section (RCS) is a comparison of two radar signal strengths. One is the strength of the radar beam sweeping over a target, the other is the strength of the reflected echo sensed by the receiver. This book shows how the RCS ?gauge? can be predicted for theoretical objects and how it can be measured for real targets. Predicting RCS is not easy, even for simple objects like spheres or cylinders, but this book explains the two ?exact? forms of theory so well that even a

  18. Radar Remote Sensing

    Science.gov (United States)

    Rosen, Paul A.

    2012-01-01

    This lecture was just a taste of radar remote sensing techniques and applications. Other important areas include Stereo radar grammetry. PolInSAR for volumetric structure mapping. Agricultural monitoring, soil moisture, ice-mapping, etc. The broad range of sensor types, frequencies of observation and availability of sensors have enabled radar sensors to make significant contributions in a wide area of earth and planetary remote sensing sciences. The range of applications, both qualitative and quantitative, continue to expand with each new generation of sensors.

  19. Wind Profiling Radar

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Clutter present in radar return signals as used for wind profiling is substantially removed by carrying out a Daubechies wavelet transformation on a time series of...

  20. Improved Laser Vibration Radar

    National Research Council Canada - National Science Library

    Hilaire, Pierre

    1998-01-01

    .... This thesis reconfigured an existing CO2 laboratory laser radar system that is capable of measuring the frequencies of vibration of a simulated target into a more compact and rugged form for field testing...

  1. Phased-array radars

    Science.gov (United States)

    Brookner, E.

    1985-02-01

    The operating principles, technology, and applications of phased-array radars are reviewed and illustrated with diagrams and photographs. Consideration is given to the antenna elements, circuitry for time delays, phase shifters, pulse coding and compression, and hybrid radars combining phased arrays with lenses to alter the beam characteristics. The capabilities and typical hardware of phased arrays are shown using the US military systems COBRA DANE and PAVE PAWS as examples.

  2. Radar detection of Vesta

    International Nuclear Information System (INIS)

    Ostro, S.J.; Cornell University, Ithaca, N.Y.); Campbell, D.B.; Pettengill, G.H.

    1980-01-01

    Asteroid 4 Vesta was detected on November 6, 1979 with the Arecibo Observatory's S-band (12.6-cm-wavelength) radar. The echo power spectrum, received in the circular polarization opposite to that transmitted, yields a radar cross section of (0.2 + or - 0.1)pi a-squared, for a 272 km. The data are too noisy to permit derivation of Vesta's rotation period

  3. Downhole pulse radar

    Science.gov (United States)

    Chang, Hsi-Tien

    1987-09-28

    A borehole logging tool generates a fast rise-time, short duration, high peak-power radar pulse having broad energy distribution between 30 MHz and 300 MHz through a directional transmitting and receiving antennas having barium titanate in the electromagnetically active region to reduce the wavelength to within an order of magnitude of the diameter of the antenna. Radar returns from geological discontinuities are sampled for transmission uphole. 7 figs.

  4. Development of passive radar systems at TNO

    NARCIS (Netherlands)

    Gelsema, S.J.

    2007-01-01

    Since 2002, the Netherlands Organisation for Applied Scientific Research – TNO, has been involved in the development of passive radar systems for research purposes. The development has been sponsored partly by the Royal Netherlands Air Force – whose main interest is threat evaluation – and partly by

  5. Overview of radar intra-pulse modulation recognition

    Science.gov (United States)

    Zang, Hanlin; Li, Yanling

    2018-05-01

    This paper introduces the current radar intra-pulse modulation method, describes the status quo and development direction of the intentional modulation and unintentional modulation in the pulse, and summarizes the existing problems and prospects for the future. Looking forward to the future, and providing a reference direction for the research on radar signal recognition in the next step.

  6. Radar Polarimetry: Theory, Analysis, and Applications

    Science.gov (United States)

    Hubbert, John Clark

    The fields of radar polarimetry and optical polarimetry are compared. The mathematics of optic polarimetry are formulated such that a local right handed coordinate system is always used to describe the polarization states. This is not done in radar polarimetry. Radar optimum polarization theory is redeveloped within the framework of optical polarimetry. The radar optimum polarizations and optic eigenvalues of common scatterers are compared. In addition a novel definition of an eigenpolarization state is given and the accompanying mathematics is developed. The polarization response calculated using optic, radar and novel definitions is presented for a variety of scatterers. Polarimetric transformation provides a means to characterize scatters in more than one polarization basis. Polarimetric transformation for an ensemble of scatters is obtained via two methods: (1) the covariance method and (2) the instantaneous scattering matrix (ISM) method. The covariance method is used to relate the mean radar parameters of a +/-45^circ linear polarization basis to those of a horizontal and vertical polarization basis. In contrast the ISM method transforms the individual time samples. Algorithms are developed for transforming the time series from fully polarimetric radars that switch between orthogonal states. The transformed time series are then used to calculate the mean radar parameters of interest. It is also shown that propagation effects do not need to be removed from the ISM's before transformation. The techniques are demonstrated using data collected by POLDIRAD, the German Aerospace Research Establishment's fully polarimetric C-band radar. The differential phase observed between two copolar states, Psi_{CO}, is composed of two phases: (1) differential propagation phase, phi_{DP}, and (2) differential backscatter phase, delta. The slope of phi_{DP } with range is an estimate of the specific differential phase, K_{DP}. The process of estimating K_{DP} is complicated when

  7. Modern Radar Techniques for Geophysical Applications: Two Examples

    Science.gov (United States)

    Arokiasamy, B. J.; Bianchi, C.; Sciacca, U.; Tutone, G.; Zirizzotti, A.; Zuccheretti, E.

    2005-01-01

    The last decade of the evolution of radar was heavily influenced by the rapid increase in the information processing capabilities. Advances in solid state radio HF devices, digital technology, computing architectures and software offered the designers to develop very efficient radars. In designing modern radars the emphasis goes towards the simplification of the system hardware, reduction of overall power, which is compensated by coding and real time signal processing techniques. Radars are commonly employed in geophysical radio soundings like probing the ionosphere; stratosphere-mesosphere measurement, weather forecast, GPR and radio-glaciology etc. In the laboratorio di Geofisica Ambientale of the Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome, Italy, we developed two pulse compression radars. The first is a HF radar called AIS-INGV; Advanced Ionospheric Sounder designed both for the purpose of research and for routine service of the HF radio wave propagation forecast. The second is a VHF radar called GLACIORADAR, which will be substituting the high power envelope radar used by the Italian Glaciological group. This will be employed in studying the sub glacial structures of Antarctica, giving information about layering, the bed rock and sub glacial lakes if present. These are low power radars, which heavily rely on advanced hardware and powerful real time signal processing. Additional information is included in the original extended abstract.

  8. Automatic identification of bird targets with radar via patterns produced by wing flapping

    NARCIS (Netherlands)

    Zaugg, S.; Saporta, G.; van Loon, E.; Schmaljohann, H.; Liechti, F.

    2008-01-01

    Bird identification with radar is important for bird migration research, environmental impact assessments (e.g. wind farms), aircraft security and radar meteorology. In a study on bird migration, radar signals from birds, insects and ground clutter were recorded. Signals from birds show a typical

  9. Environmental effects on the radar signature of maritime targets and assets

    NARCIS (Netherlands)

    Heemskerk, H.J.M.

    1999-01-01

    The member nations of task group 5 (TG05) of the NATO AC/323 SET panel have conducted the cooperative research project Livorno'96 to investigate the dependence of the radar signature on radar, geometrical and target parameters, and to investigate the environmental effects on the measured radar

  10. CAMEX-4 TOGA RADAR V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The TOGA radar dataset consists of browse and radar data collected from the TOGA radar during the CAMEX-4 experiment. TOGA is a C-band linear polarized doppler radar...

  11. Analysis and Simulation of Multi-target Echo Signals from a Phased Array Radar

    OpenAIRE

    Jia Zhen; Zhou Rui

    2017-01-01

    The construction of digital radar simulation systems has been a research hotspot of the radar field. This paper focuses on theoretical analysis and simulation of multi-target echo signals produced in a phased array radar system, and constructs an array antenna element and a signal generation environment. The antenna element is able to simulate planar arrays and optimizes these arrays by adding window functions. And the signal environment can model and simulate radar transmission signals, rada...

  12. Radar Scan Methods in Modern Multifunctional Radars

    Directory of Open Access Journals (Sweden)

    V. N. Skosyrev

    2014-01-01

    Full Text Available Considered urgent task of organizing the review space in modern multifunctional radar systems shall review the space in a wide range of elevation angles from minus 5 to 60-80 degrees and 360 degrees azimuth. MfRLS this type should provide an overview of the zone for a limited time (2-3 sec, detecting a wide range of subtle high and low-flying targets. The latter circumstance requires the organization to select targets against the background of reflections from the underlying surface and local objects (MP. When providing an overview of the space taken into account the need to increase not only the noise immunity, and survivability.Two variants of the review of space in the elevation plane in the solid-state AESA radar. In the first case the overview space narrow beam by one beam. In the second - the transfer of DNA is formed, covering the whole sector of responsibility in elevation and at the reception beam is formed in spetsvychislitele (CB as a result of the signal processing of digitized after emitters antenna web. The estimations of the parameters specific to the multifunction radar SAM air and missile defense. It is shown that in a number of practically important cases, preference should be given clearly one of the methods described review of space.The functional scheme with AESA radar for both variants of the review. Necessary to analyze their differences. Contains the problem of increasing the cost of MfRLS with digital beamforming DNA with increasing bandwidth probing signal being processed.Noted drawbacks of MfRLS with digital beamforming beam. Including: reduced accuracy of the coordinates at low elevation angles, the complexity of the organization of thermal regime of the solid element base using quasi-continuous signal with a low duty cycle. Shows their fundamentally unavoidable in the steppe and desert areas with uneven terrain (Kazakhstan, China, the Middle East.It is shown that for MfRLS working in strong clutter, more preferably

  13. Ground Radar Polarimetric Observations of High-Frequency Earth-Space Communication Links

    Science.gov (United States)

    Bolen, Steve; Chandrasekar, V.; Benjamin, Andrew

    2002-01-01

    Strategic roadmaps for NASA's Human Exploration and Development of Space (REDS) enterprise support near-term high-frequency communication systems that provide moderate to high data rates with dependable service. Near-earth and human planetary exploration will baseline Ka-Band, but may ultimately require the use of even higher frequencies. Increased commercial demand on low-frequency earth-space bands has also led to increased interest in the use of higher frequencies in regions like K u - and K,- band. Data is taken from the Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR), which operates at 13.8 GHz, and the true radar reflectivity profile is determined along the PR beam via low-frequency ground based polarimetric observations. The specific differential phase (Kdp) is measured along the beam and a theoretical model is used to determine the expected specific attenuation (k). This technique, called the k-Kdp method, uses a Fuzzy-Logic model to determine the hydrometeor type along the PR beam from which the appropriate k-Kdp relationship is used to determine k and, ultimately, the total path-integrated attenuation (PIA) on PR measurements. Measurements from PR and the NCAR S-POL radar were made during the TEFLUN-B experiment that took place near Melbourne, FL in 1998, and the TRMM-LBA campaign near Ji-Parana, Brazil in 1999.

  14. Micropower radar systems for law enforcement technology

    Energy Technology Data Exchange (ETDEWEB)

    Azevedo, S.G.; Mast, J.; Brase, J. [Lawrence Livermore National Lab., CA (United States)] [and others

    1994-11-15

    LLNL researchers have pioneered a unique compact low-power and inexpensive radar technology (microradar) that has enormous potential in various industries. Some licenses are currently in place for motion sensors and stud finders. The ultra-wideband characteristics of the microradar (4 to 10 GHz) make it difficult to detect, yet provide potential range resolution of 1 cm at ranges of greater than 20 meters. Real and synthetic apertures arrays of radar elements can address imaging applications behind walls at those distances. Personnel detection applications are currently being tested.

  15. Measuring Balance Across Multiple Radar Receiver Channels.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin W.; Bickel, Douglas L.

    2018-03-01

    When radar receivers employ multiple channels, the general intent is for the receive channels to be as alike as possible, if not as ideal as possible. This is usually done via prudent hardware design, supplemented by system calibration. Towards this end, we require a quality metric for ascertaining the goodness of a radar channel, and the degree of match to sibling channels. We propose a relevant and useable metric to do just that. Acknowledgements This report was the result of an unfunded research and development activity.

  16. Ground penetrating radar

    CERN Document Server

    Daniels, David J

    2004-01-01

    Ground-penetrating radar has come to public attention in recent criminal investigations, but has actually been a developing and maturing remote sensing field for some time. In the light of recent expansion of the technique to a wide range of applications, the need for an up-to-date reference has become pressing. This fully revised and expanded edition of the best-selling Surface-Penetrating Radar (IEE, 1996) presents, for the non-specialist user or engineer, all the key elements of this technique, which span several disciplines including electromagnetics, geophysics and signal processing. The

  17. Radar-acoustic interaction for IFF applications

    Science.gov (United States)

    Saffold, James A.; Williamson, Frank R.; Ahuja, Krishan; Stein, Lawrence R.; Muller, Marjorie

    1998-08-01

    This paper describes the results of an internal development program (IDP) No. 97-1 conducted from August 1-October 1 1996 at the Georgia Tech Research Institute. The IDP program was implemented to establish theoretical relationships and verify the interaction between X-band radar waves and ultrasonic acoustics. Low cost, off-the-shelf components were used for the verification in order to illustrate the cost savings potential of developing and utilizing these systems. The measured data was used to calibrate the developed models of the phenomenology and to support extrapolation for radar systems which can exploit these interactions. One such exploitation is for soldier identification IFF and radar taggant concepts. The described IDP program provided the phenomenological data which is being used to extrapolate concept system performances based on technological limitations and battlefield conditions for low cost IFF and taggant configurations.

  18. Systems and Methods for Radar Data Communication

    Science.gov (United States)

    Bunch, Brian (Inventor); Szeto, Roland (Inventor); Miller, Brad (Inventor)

    2013-01-01

    A radar information processing system is operable to process high bandwidth radar information received from a radar system into low bandwidth radar information that may be communicated to a low bandwidth connection coupled to an electronic flight bag (EFB). An exemplary embodiment receives radar information from a radar system, the radar information communicated from the radar system at a first bandwidth; processes the received radar information into processed radar information, the processed radar information configured for communication over a connection operable at a second bandwidth, the second bandwidth lower than the first bandwidth; and communicates the radar information from a radar system, the radar information communicated from the radar system at a first bandwidth.

  19. Human walking estimation with radar

    NARCIS (Netherlands)

    Dorp, Ph. van; Groen, F.C.A.

    2003-01-01

    Radar can be used to observe humans that are obscured by objects such as walls. These humans cannot be visually observed. The radar measurements are used to animate an obscured human in virtual reality. This requires detailed information about the motion. The radar measurements give detailed

  20. Radar meteors range distribution model. I. Theory

    Czech Academy of Sciences Publication Activity Database

    Pecinová, Drahomíra; Pecina, Petr

    2007-01-01

    Roč. 37, č. 2 (2007), s. 83-106 ISSN 1335-1842 R&D Projects: GA ČR GA205/03/1405 Institutional research plan: CEZ:AV0Z10030501 Keywords : physics of meteors * radar meteors * range distribution Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  1. Single Frequency Network Based Distributed Passive Radar Technology

    Directory of Open Access Journals (Sweden)

    Wan Xian-rong

    2015-01-01

    Full Text Available The research and application of passive radar are heading from single transmitter-receiver pair to multiple transmitter-receiver pairs. As an important class of the illuminators of opportunity, most of modern digital broadcasting and television systems work on Single Frequency Network (SFN, which intrinsically determines that the passive radar based on such illuminators must be distributed and networked. In consideration of the remarkable working and processing mode of passive radar under SFN configuration, this paper proposes the concept of SFN-based Distributed Passive Radar (SDPR. The main characteristics and key problems of SDPR are first described. Then several potential solutions are discussed for part of the key technologies. The feasibility of SDPR is demonstrated by preliminary experimental results. Finally, the concept of four network convergence that includes the broadcast based passive radar network is conceived, and its application prospects are discussed.

  2. Target Detection Based on EBPSK Satellite Passive Radar

    Directory of Open Access Journals (Sweden)

    Lu Zeyuan

    2015-05-01

    Full Text Available Passive radar is a topic anti stealth technology with simple structure, and low cost. Radiation source model, signal transmission model, and target detection are the key points of passive radar technology research. The paper analyzes the characteristics of EBPSK signal modulation and target detection method aspect of spaceborne radiant source. By comparison with other satellite navigation and positioning system, the characteristics of EBPSK satellite passive radar system are analyzed. It is proved that the maximum detection range of EBPSK satellite signal can satisfy the needs of the proposed model. In the passive radar model, sparse representation is used to achieve high resolution DOA detection. The comparison with the real target track by simulation demonstrates that effective detection of airborne target using EBPSK satellite passive radar system based on sparse representation is efficient.

  3. Development of Bread Board Model of TRMM precipitation radar

    Science.gov (United States)

    Okamoto, Ken'ichi; Ihara, Toshio; Kumagai, Hiroshi

    The active array radar was selected as a reliable candidate for the TRMM (Tropical Rainfall Measuring Mission) precipitation radar after the trade off studies performed by Communications Research Laboratory (CRL) in the US-Japan joint feasibility study of TRMM in 1987-1988. Main system parameters and block diagram for TRMM precipitation radar are shown as the result of feasibility study. CRL developed key devices for the active array precipitation radar such as 8-element slotted waveguide array antenna, the 5 bit PIN diode phase shifters, solid state power amplifiers and low noise amplifiers in 1988-1990. Integration of these key devices was made to compose 8-element Bread Board Model of TRMM precipitation radar.

  4. Netted LPI RADARs

    Science.gov (United States)

    2011-09-01

    CHALLENGES ............................66 1. Radar Processing Gain ........................66 2. High Sensitivity Requirement .................68 B...Relationship Between Network Space and Challenges .....................................127 Figure 42. Maneuverability................................129...virtually any kind of terrain. It has five modes: Normal, Weather, ECCM, LPI, and Very Low Clearance ( VLC ). Pictures of the LANTIRN pod aboard and F-16

  5. Proceedings of the COST 75 final seminar on advanced weather radar systems; Beitraege des Instituts zum COST 75 final seminar on advanced weather radar systems

    Energy Technology Data Exchange (ETDEWEB)

    Baumann, R.; Flender, F.; Hagen, M.; Hoeller, H.; Keil, C.; Meischner, P.

    1998-07-01

    Across Europe more than 110 weather radars are in operation. More than 60 of them are Doppler radars and this number is increasing steadily. Doppler systems are becoming an operational standard. Most systems operate in C-band, with the exception of the Spanish radar network which is composed of S-band Doppler radars. Radar product composites are available for Scandinavia and Central Europe. National networks exist for the UK, France and Spain. Europe further is fortunate to have 8 polarimetric Doppler radars used mainly for research. In Italy some of those systems are used also for operational nowcasting applications for dedicated customers. The Chilbolton multiparameter Doppler radar operates at S-band. (orig.)

  6. Active microwave remote sensing research program plan. Recommendations of the Earth Resources Synthetic Aperture Radar Task Force. [application areas: vegetation canopies, surface water, surface morphology, rocks and soils, and man-made structures

    Science.gov (United States)

    1980-01-01

    A research program plan developed by the Office of Space and Terrestrial Applications to provide guidelines for a concentrated effort to improve the understanding of the measurement capabilities of active microwave imaging sensors, and to define the role of such sensors in future Earth observations programs is outlined. The focus of the planned activities is on renewable and non-renewable resources. Five general application areas are addressed: (1) vegetation canopies, (2) surface water, (3) surface morphology, (4) rocks and soils, and (5) man-made structures. Research tasks are described which, when accomplished, will clearly establish the measurement capabilities in each area, and provide the theoretical and empirical results needed to specify and justify satellite systems using imaging radar sensors for global observations.

  7. Spaceborne synthetic aperture radar: Current status and future directions. A report to the Committee on Earth Sciences, Space Studies Board, National Research Council

    Science.gov (United States)

    Evans, D. L. (Editor); Apel, J.; Arvidson, R.; Bindschadler, R.; Carsey, F.; Dozier, J.; Jezek, K.; Kasischke, E.; Li, F.; Melack, J.

    1995-01-01

    This report provides a context in which questions put forth by NASA's Office of Mission to Planet Earth (OMPTE) regarding the next steps in spaceborne synthetic aperture radar (SAR) science and technology can be addressed. It summarizes the state-of-the-art in theory, experimental design, technology, data analysis, and utilization of SAR data for studies of the Earth, and describes potential new applications. The report is divided into five science chapters and a technology assessment. The chapters summarize the value of existing SAR data and currently planned SAR systems, and identify gaps in observational capabilities needing to be filled to address the scientific questions. Cases where SAR provides complementary data to other (non-SAR) measurement techniques are also described. The chapter on technology assessment outlines SAR technology development which is critical not only to NASA's providing societally relevant geophysical parameters but to maintaining competitiveness in SAR technology, and promoting economic development.

  8. NAMMA NASA POLARIMETRIC DOPPLER WEATHER RADAR (NPOL) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The NAMMA NASA Polarimetric Doppler Weather Radar (NPOL) dataset used the NPOL, developed by a research team from Wallops Flight Facility, is a fully transportable...

  9. The development of deep learning in synthetic aperture radar imagery

    CSIR Research Space (South Africa)

    Schwegmann, Colin P

    2017-05-01

    Full Text Available sensing techniques but comes at the price of additional complexities. To adequately cope with these, researchers have begun to employ advanced machine learning techniques known as deep learning to Synthetic Aperture Radar data. Deep learning represents...

  10. Assimilation of Doppler weather radar observations in a mesoscale ...

    Indian Academy of Sciences (India)

    Research (PSU–NCAR) mesoscale model (MM5) version 3.5.6. The variational data assimilation ... investigation of the direct assimilation of radar reflectivity data in 3DVAR system. The present ...... Results presented in this paper are based on.

  11. The use of radar for bathymetry assessment

    OpenAIRE

    Aardoom, J.H.; Greidanus, H.S.F.

    1998-01-01

    The bottom topography in shallow seas can be observed by air- and spaceborne imaging radar. Bathymetric information derived from radar data is limited in accuracy, but radar has a good spatial coverage. The accuracy can be increased by assimilating the radar imagery into existing or insitu gathered bathymetric data. The paper reviews the concepts of bathymetry assessment by radar, the radar imaging mechanism, and the possibilities and limitations of the use of radar data in rapid assessment.

  12. Radar detection of ultra high energy cosmic rays

    Science.gov (United States)

    Myers, Isaac J.

    TARA (Telescope Array Radar) is a cosmic ray radar detection experiment co-located with Telescope Array, the conventional surface scintillation detector (SD) and fluorescence telescope detector (FD) near Delta, UT. The TARA detector combines a 40 kW transmitter and high gain transmitting antenna which broadcasts the radar carrier over the SD array and in the FD field of view to a 250 MS/s DAQ receiver. Data collection began in August, 2013. TARA stands apart from other cosmic ray radar experiments in that radar data is directly compared with conventional cosmic ray detector events. The transmitter is also directly controlled by TARA researchers. Waveforms from the FD-triggered data stream are time-matched with TA events and searched for signal using a novel signal search technique in which the expected (simulated) radar echo of a particular air shower is used as a matched filter template and compared to radio waveforms. This technique is used to calculate the radar cross-section (RCS) upper-limit on all triggers that correspond to well-reconstructed TA FD monocular events. Our lowest cosmic ray RCS upper-limit is 42 cm2 for an 11 EeV event. An introduction to cosmic rays is presented with the evolution of detection and the necessity of new detection techniques, of which radar detection is a candidate. The software simulation of radar scattering from cosmic rays follows. The TARA detector, including transmitter and receiver systems, are discussed in detail. Our search algorithm and methodology for calculating RCS is presented for the purpose of being repeatable. Search results are explained in context of the usefulness and future of cosmic ray radar detection.

  13. FY 2001 report on the integrated evaluation of the research cooperation project. Research cooperation program on the development of environmental measurement use laser radar/research cooperation project on the mining waste water treatment technology using biology; 2001 nendo kenkyu kyoryoku jigyo sogo hyoka hokokusho. Kankyo kesokuyo reza reda no kaihatsu ni kansuru kenkyu kyoryoku - Baio riyo ni yoru kohaisui shori gijutsu ni kansuru kenkyu kyoryoku

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-03-01

    By research groups having been sent, the integrated evaluation was made of the projects on the research cooperation with Indonesia in the development of environmental measurement use laser radar and the research cooperation with China in the mining waste water treatment technology using biology. As to the research cooperation with Indonesia, the purpose/target proposed were almost achieved, and all were favorably carried out. Especially, after finishing the project, the design/manufacture of an on-vehicle type Mie-scattering laser radar were made using the acquired laser technology. And, it was reported that an observation study of the state of air pollution in Bandung city was made using the laser radar. It can be said that generally the research cooperation with China was smoothly proceeded with. However, the Wushan mine is small in scale of management, and therefore, there might have been some points to be reviewed in selection of the mine for research. The pilot plant installed at the Wushan mine is not now operated. If the mine has strong management force, the effective use of the pilot plant after finishing the project might have been studied. (NEDO)

  14. Power centroid radar and its rise from the universal cybernetics duality

    Science.gov (United States)

    Feria, Erlan H.

    2014-05-01

    Power centroid radar (PC-Radar) is a fast and powerful adaptive radar scheme that naturally surfaced from the recent discovery of the time-dual for information theory which has been named "latency theory." Latency theory itself was born from the universal cybernetics duality (UC-Duality), first identified in the late 1970s, that has also delivered a time dual for thermodynamics that has been named "lingerdynamics" and anchors an emerging lifespan theory for biological systems. In this paper the rise of PC-Radar from the UC-Duality is described. The development of PC-Radar, US patented, started with Defense Advanced Research Projects Agency (DARPA) funded research on knowledge-aided (KA) adaptive radar of the last decade. The outstanding signal to interference plus noise ratio (SINR) performance of PC-Radar under severely taxing environmental disturbances will be established. More specifically, it will be seen that the SINR performance of PC-Radar, either KA or knowledgeunaided (KU), approximates that of an optimum KA radar scheme. The explanation for this remarkable result is that PC-Radar inherently arises from the UC-Duality, which advances a "first principles" duality guidance theory for the derivation of synergistic storage-space/computational-time compression solutions. Real-world synthetic aperture radar (SAR) images will be used as prior-knowledge to illustrate these results.

  15. Comet radar explorer

    Science.gov (United States)

    Farnham, Tony; Asphaug, Erik; Barucci, Antonella; Belton, Mike; Bockelee-Morvan, Dominique; Brownlee, Donald; Capria, Maria Teresa; Carter, Lynn; Chesley, Steve; Farnham, Tony; Gaskell, Robert; Gim, Young; Heggy, Essam; Herique, Alain; Klaasen, Ken; Kofman, Wlodek; Kreslavsky, Misha; Lisse, Casey; Orosei, Roberto; Plaut, Jeff; Scheeres, Dan

    The Comet Radar Explorer (CORE) is designed to perform a comprehensive and detailed exploration of the interior, surface, and inner coma structures of a scientifically impor-tant Jupiter family comet. These structures will be used to investigate the origins of cometary nuclei, their physical and geological evolution, and the mechanisms driving their spectacular activity. CORE is a high heritage spacecraft, injected by solar electric propulsion into orbit around a comet. It is capable of coherent deep radar imaging at decameter wavelengths, high resolution stereo color imaging, and near-IR imaging spectroscopy. Its primary objective is to obtain a high-resolution map of the interior structure of a comet nucleus at a resolution of ¿100 elements across the diameter. This structure shall be related to the surface geology and morphology, and to the structural details of the coma proximal to the nucleus. This is an ideal complement to the science from recent comet missions, providing insight into how comets work. Knowing the structure of the interior of a comet-what's inside-and how cometary activity works, is required before we can understand the requirements for a cryogenic sample return mission. But more than that, CORE is fundamental to understanding the origin of comets and their evolution in time. The mission is made feasible at low cost by the use of now-standard MARSIS-SHARAD reflec-tion radar imaging hardware and data processing, together with proven flight heritage of solar electric propulsion. Radar flight heritage has been demonstrated by the MARSIS radar on Mars Express (Picardi et al., Science 2005; Plaut et al., Science 2007), the SHARAD radar onboard the Mars Reconnaissance Orbiter (Seu et al., JGR 2007), and the LRS radar onboard Kaguya (Ono et al, EPS 2007). These instruments have discovered detailed subsurface structure to depths of several kilometers in a variety of terrains on Mars and the Moon. A reflection radar deployed in orbit about a comet

  16. [Radar as imaging tool in ecology and conservation biology].

    Science.gov (United States)

    Matyjasiak, Piotr

    2017-01-01

    Migrations and dispersal are among the most important ecological processes that shape ecosystems and influence our economy, health and safety. Movements of birds, bats and insects occur in a large spatial scale - regional, continental, or intercontinental. However, studies of these phenomena using classic methods are usually local. Breakthrough came with the development of radar technology, which enabled researchers to study animal movements in the atmosphere in a large spatial and temporal scale. The aim of this article was to present the radar imaging methods used in the research of aerial movements of birds, bats and insects. The types of radars used in research are described, and examples of the use of radar in basic research and in conservation biology are discussed. Radar visualizations are used in studies on the effect of meteorological conditions on bird migration, on spatial and temporal dynamics of movements of birds, bats and insects, and on the mechanism of orientation of migrating birds and insects. In conservation biology research radars are used in the monitoring of endangered species of birds and bats, to monitor bird activity at airports, as well as in assessing the impact of high constructions on flying birds and bats.

  17. System aspects of the Indian MST radar facility

    Science.gov (United States)

    Viswanathan, G.

    1986-01-01

    One of the major objectives of the Indian Middle Atmosphere Program is to investigate the motions of the middle atmosphere on temporal and spatial scales and the interaction between the three height regions of the middle atmosphere. Realizing the fact that radar technique has proven to be a very powerful tool for the study of Earth atmosphere, the Indian Middle Atmosphere Program has recommended establishing a mesosphere-stratosphere-troposphere (MST) radar as a national facility for atmospheric research. The major landmarks in this attempt to setup the MST radar as a national facility are described.

  18. A review of array radars

    Science.gov (United States)

    Brookner, E.

    1981-10-01

    Achievements in the area of array radars are illustrated by such activities as the operational deployment of the large high-power, high-range-resolution Cobra Dane; the operational deployment of two all-solid-state high-power, large UHF Pave Paws radars; and the development of the SAM multifunction Patriot radar. This paper reviews the following topics: array radars steered in azimuth and elevation by phase shifting (phase-phase steered arrays); arrays steered + or - 60 deg, limited scan arrays, hemispherical coverage, and omnidirectional coverage arrays; array radars steering electronically in only one dimension, either by frequency or by phase steering; and array radar antennas which use no electronic scanning but instead use array antennas for achieving low antenna sidelobes.

  19. FMWC Radar for Breath Detection

    DEFF Research Database (Denmark)

    Suhr, Lau Frejstrup; Tafur Monroy, Idelfonso; Vegas Olmos, Juan José

    We report on the experimental demonstration of an FMCW radar operating in the 25.7 - 26.6 GHz range with a repetition rate of 500 sweeps per second. The radar is able to track the breathing rate of an adult human from a distance of 1 meter. The experiments have utilized a 50 second recording window...... to accurately track the breathing rate. The radar utilizes a saw tooth modulation format and a low latency receiver. A breath tracking radar is useful both in medical scenarios, diagnosing disorders such as sleep apnea, and for home use where the user can monitor its health. Breathing is a central part of every...... radar chip which, through the use of a simple modulation scheme, is able to measure the breathing rate of an adult human from a distance. A high frequency output makes sure that the radar cannot penetrate solid obstacles which is a wanted feature in private homes where people therefore cannot measure...

  20. Enhanced research in ground-penetrating radar and multisensor fusion with application to the detection and visualization of buried waste. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Devney, A.J.; DiMarzio, C.; Kokar, M.; Miller, E.L.; Rappaport, C.M.; Weedon, W.H.

    1996-05-14

    Recognizing the difficulty and importance of the landfill remediation problems faced by DOE, and the fact that no one sensor alone can provide complete environmental site characterization, a multidisciplinary team approach was chosen for this project. The authors have developed a multisensor fusion approach that is suitable for the wide variety of sensors available to DOE, that allows separate detection algorithms to be developed and custom-tailored to each sensor. This approach is currently being applied to the Geonics EM-61 and Coleman step-frequency radar data. High-resolution array processing techniques were developed for detecting and localizing buried waste containers. A soil characterization laboratory facility was developed using a HP-8510 network analyzer and near-field coaxial probe. Both internal and external calibration procedures were developed for de-embedding the frequency-dependent soil electrical parameters from the measurements. Dispersive soil propagation modeling algorithms were also developed for simulating wave propagation in dispersive soil media. A study was performed on the application of infrared sensors to the landfill remediation problem, particularly for providing information on volatile organic compounds (VOC`s) in the atmosphere. A dust-emission lidar system is proposed for landfill remediation monitoring. Design specifications are outlined for a system which could be used to monitor dust emissions in a landfill remediation effort. The detailed results of the investigations are contained herein.

  1. Enhanced research in ground-penetrating radar and multisensor fusion with application to the detection and visualization of buried waste. Final report

    International Nuclear Information System (INIS)

    Devney, A.J.; DiMarzio, C.; Kokar, M.; Miller, E.L.; Rappaport, C.M.; Weedon, W.H.

    1996-01-01

    Recognizing the difficulty and importance of the landfill remediation problems faced by DOE, and the fact that no one sensor alone can provide complete environmental site characterization, a multidisciplinary team approach was chosen for this project. The authors have developed a multisensor fusion approach that is suitable for the wide variety of sensors available to DOE, that allows separate detection algorithms to be developed and custom-tailored to each sensor. This approach is currently being applied to the Geonics EM-61 and Coleman step-frequency radar data. High-resolution array processing techniques were developed for detecting and localizing buried waste containers. A soil characterization laboratory facility was developed using a HP-8510 network analyzer and near-field coaxial probe. Both internal and external calibration procedures were developed for de-embedding the frequency-dependent soil electrical parameters from the measurements. Dispersive soil propagation modeling algorithms were also developed for simulating wave propagation in dispersive soil media. A study was performed on the application of infrared sensors to the landfill remediation problem, particularly for providing information on volatile organic compounds (VOC's) in the atmosphere. A dust-emission lidar system is proposed for landfill remediation monitoring. Design specifications are outlined for a system which could be used to monitor dust emissions in a landfill remediation effort. The detailed results of the investigations are contained herein

  2. Micropower impulse radar technology and applications

    Energy Technology Data Exchange (ETDEWEB)

    Mast, J., LLNL

    1998-04-15

    The LLNL-developed Micropower Impulse Radar (MIR) technology has quickly gone from laboratory concept to embedded circuitry in numerous government and commercial systems in the last few years[l]. The main ideas behind MIR, invented by T. McEwan in the Laser Program, are the generation and detection systems for extremely low- power ultra-wideband pulses in the gigaHertz regime using low-cost components. These ideas, coupled with new antenna systems, timing and radio-frequency (RF) circuitry, computer interfaces, and signal processing, have provided the catalyst for a new generation of compact radar systems. Over the past several years we have concentrated on a number of applications of MIR which address a number of remote-sensing applications relevant to emerging programs in defense, transportation, medical, and environmental research. Some of the past commercial successes have been widely publicized [2] and are only now starting to become available for market. Over 30 patents have been filed and over 15 licenses have been signed on various aspects of the MIR technology. In addition, higher performance systems are under development for specific laboratory programs and government reimbursables. The MIR is an ultra- wideband, range-gated radar system that provides the enabling hardware technology used in the research areas mentioned above. It has numerous performance parameters that can be Selected by careful design to fit the requirements. We have improved the baseline, short- range, MIR system to demonstrate its effectiveness. The radar operates over the hand from approximately I to 4 GHz with pulse repetition frequencies up to 10 MHz. It provides a potential range resolution of I cm at ranges of greater than 20 m. We have developed a suite of algorithms for using MIR for image formation. These algorithms currently support Synthetic aperture and multistate array geometries. This baseline MIR radar imaging system has been used for several programmatic applications.

  3. Radar Image, Hokkaido, Japan

    Science.gov (United States)

    2000-01-01

    The southeast part of the island of Hokkaido, Japan, is an area dominated by volcanoes and volcanic caldera. The active Usu Volcano is at the lower right edge of the circular Lake Toya-Ko and near the center of the image. The prominent cone above and to the left of the lake is Yotei Volcano with its summit crater. The city of Sapporo lies at the base of the mountains at the top of the image and the town of Yoichi -- the hometown of SRTM astronaut Mamoru Mohri -- is at the upper left edge. The bay of Uchiura-Wan takes up the lower center of the image. In this image, color represents elevation, from blue at the lowest elevations to white at the highest. The radar image has been overlaid to provide more details of the terrain. Due to a processing problem, an island in the center of this crater lake is missing and will be properly placed when further SRTM swaths are processed. The horizontal banding in this image is a processing artifact that will be removed when the navigation information collected by SRTM is fully calibrated. This image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC. Size: 100 by 150 kilometers (62

  4. Motion measurement for synthetic aperture radar

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-01-01

    Synthetic Aperture Radar (SAR) measures radar soundings from a set of locations typically along the flight path of a radar platform vehicle. Optimal focusing requires precise knowledge of the sounding source locations in 3-D space with respect to the target scene. Even data driven focusing techniques (i.e. autofocus) requires some degree of initial fidelity in the measurements of the motion of the radar. These requirements may be quite stringent especially for fine resolution, long ranges, and low velocities. The principal instrument for measuring motion is typically an Inertial Measurement Unit (IMU), but these instruments have inherent limi ted precision and accuracy. The question is %22How good does an IMU need to be for a SAR across its performance space?%22 This report analytically relates IMU specifications to parametric requirements for SAR. - 4 - Acknowledgements Th e preparation of this report is the result of a n unfunded research and development activity . Although this report is an independent effort, it draws heavily from limited - release documentation generated under a CRADA with General Atomics - Aeronautical System, Inc. (GA - ASI), and under the Joint DoD/DOE Munitions Program Memorandum of Understanding. Sandia National Laboratories is a multi - program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of En ergy's National Nuclear Security Administration under contract AC04-94AL85000.

  5. Bistatic Forward Scattering Radar Detection and Imaging

    Directory of Open Access Journals (Sweden)

    Hu Cheng

    2016-06-01

    Full Text Available Forward Scattering Radar (FSR is a special type of bistatic radar that can implement image detection, imaging, and identification using the forward scattering signals provided by the moving targets that cross the baseline between the transmitter and receiver. Because the forward scattering effect has a vital significance in increasing the targets’ Radar Cross Section (RCS, FSR is quite advantageous for use in counter stealth detection. This paper first introduces the front line technology used in forward scattering RCS, FSR detection, and Shadow Inverse Synthetic Aperture Radar (SISAR imaging and key problems such as the statistical characteristics of forward scattering clutter, accurate parameter estimation, and multitarget discrimination are then analyzed. Subsequently, the current research progress in FSR detection and SISAR imaging are described in detail, including the theories and experiments. In addition, with reference to the BeiDou navigation satellite, the results of forward scattering experiments in civil aircraft detection are shown. Finally, this paper considers future developments in FSR target detection and imaging and presents a new, promising technique for stealth target detection.

  6. Space Radar Image of Bahia

    Science.gov (United States)

    1994-01-01

    limited by the nearly continuous cloud cover in the region and heavy rainfall, which occurs more than 150 days each year. The ability of the shuttle radars to 'see' through the forest canopy to the cultivated cacao below -- independent of weather or sunlight conditions --will allow researchers to distinguish forest from cabruca in unprecedented detail. This SIR-C/X-SAR image was produced by assigning red to the L-band, green to the C-band and blue to the X-band. The Una Reserve is located in the middle of the image west of the coastline and slightly northwest of Comandatuba River. The reserve's primary forests are easily detected by the pink areas in the image. The intensity of red in these areas is due to the high density of forest vegetation (biomass) detected by the radar's L-band (horizontally transmitted and vertically received) channel. Secondary forest is visible along the reserve's eastern border. The Serrado Mar mountain range is located in the top left portion of the image. Cabruca forest to the west of Una Reserve has a different texture and a yellow color. The removal of understory in cabruca forest reduces its biomass relative to primary forest, which changes the L-band and C-band penetration depth and returns, and produces a different texture and color in the image. The region along the Atlantic is mainly mangrove swamp, agricultural fields and urban areas. The high intensity of blue in this region is a result of increasing X-band return in areas covered with swamp and low vegetation. The image clearly separates the mangrove region (east of coastal Highway 001, shown in blue) from the taller and dryer forest west of the highway. The high resolution capability of SIR-C/X-SAR imaging and the sensitivity of its frequency and polarization channels to various land covers will be used for monitoring and mapping areas of importance for conservation. Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar(SIR-C/X-SAR) is part of NASA's Mission to Planet Earth

  7. Radar techniques using array antennas

    CERN Document Server

    Wirth, Wulf-Dieter

    2013-01-01

    Radar Techniques Using Array Antennas is a thorough introduction to the possibilities of radar technology based on electronic steerable and active array antennas. Topics covered include array signal processing, array calibration, adaptive digital beamforming, adaptive monopulse, superresolution, pulse compression, sequential detection, target detection with long pulse series, space-time adaptive processing (STAP), moving target detection using synthetic aperture radar (SAR), target imaging, energy management and system parameter relations. The discussed methods are confirmed by simulation stud

  8. The Next Generation Airborne Polarimetric Doppler Radar

    Science.gov (United States)

    Vivekanandan, J.; Lee, Wen-Chau; Loew, Eric; Salazar, Jorge; Chandrasekar, V.

    2013-04-01

    NCAR's Electra Doppler radar (ELDORA) with a dual-beam slotted waveguide array using dual-transmitter, dual-beam, rapid scan and step-chirped waveform significantly improved the spatial scale to 300m (Hildebrand et al. 1996). However, ELDORA X-band radar's penetration into precipitation is limited by attenuation and is not designed to collect polarimetric measurements to remotely estimate microphysics. ELDORA has been placed on dormancy because its airborne platform (P3 587) was retired in January 2013. The US research community has strongly voiced the need to continue measurement capability similar to the ELDORA. A critical weather research area is quantitative precipitation estimation/forecasting (QPE/QPF). In recent years, hurricane intensity change involving eye-eyewall interactions has drawn research attention (Montgomery et al., 2006; Bell and Montgomery, 2006). In the case of convective precipitation, two issues, namely, (1) when and where convection will be initiated, and (2) determining the organization and structure of ensuing convection, are key for QPF. Therefore collocated measurements of 3-D winds and precipitation microphysics are required for achieving significant skills in QPF and QPE. Multiple radars in dual-Doppler configuration with polarization capability estimate dynamical and microphysical characteristics of clouds and precipitation are mostly available over land. However, storms over complex terrain, the ocean and in forest regions are not observable by ground-based radars (Bluestein and Wakimoto, 2003). NCAR/EOL is investigating potential configurations for the next generation airborne radar that is capable of retrieving dynamic and microphysical characteristics of clouds and precipitation. ELDORA's slotted waveguide array radar is not compatible for dual-polarization measurements. Therefore, the new design has to address both dual-polarization capability and platform requirements to replace the ELDORA system. NCAR maintains a C-130

  9. Combining Lidar and Synthetic Aperture Radar Data to Estimate Forest Biomass: Status and Prospects

    Directory of Open Access Journals (Sweden)

    Sanna Kaasalainen

    2015-01-01

    Full Text Available Research activities combining lidar and radar remote sensing have increased in recent years. The main focus in combining lidar-radar forest remote sensing has been on the retrieval of the aboveground biomass (AGB, which is a primary variable related to carbon cycle in land ecosystems, and has therefore been identified as an essential climate variable. In this review, we summarize the studies combining lidar and radar in estimating forest AGB. We discuss the complementary use of lidar and radar according to the relevance of the added value. The most promising prospects for combining lidar and radar data are in the use of lidar-derived ground elevations for improving large-area biomass estimates from radar, and in upscaling of lidar-based AGB data across large areas covered by spaceborne radar missions.

  10. The Python ARM Radar Toolkit (Py-ART), a Library for Working with Weather Radar Data in the Python Programming Language

    OpenAIRE

    Helmus, Jonathan J; Collis, Scott M

    2016-01-01

    The Python ARM Radar Toolkit is a package for reading, visualizing, correcting and analysing data from weather radars. Development began to meet the needs of the Atmospheric Radiation Measurement Climate Research Facility and has since expanded to provide a general-purpose framework for working with data from weather radars in the Python programming language. The toolkit is built on top of libraries in the Scientific Python ecosystem including NumPy, SciPy, and matplotlib, and makes use of Cy...

  11. Wind profile radar for study of Antarctic air circulation

    International Nuclear Information System (INIS)

    Ragaini, E.; Sarango, M.F.; Vasquez, E.H.

    1992-01-01

    After a brief discussion of meteorological methods used in the Antarctic, the paper gives an outline of a coordinated international research project whose objective is to set up a wind profiler radar station that would give meteorologists information regarding Antarctic atmospheric dynamics useful in their investigation of the causes and effects of the hole in the ozone layer. The radar instrumentation is to provide continuous readings of wind velocity at varying altitudes above the polar continent

  12. Broadview Radar Altimetry Toolbox

    Science.gov (United States)

    Garcia-Mondejar, Albert; Escolà, Roger; Moyano, Gorka; Roca, Mònica; Terra-Homem, Miguel; Friaças, Ana; Martinho, Fernando; Schrama, Ernst; Naeije, Marc; Ambrózio, Américo; Restano, Marco; Benveniste, Jérôme

    2017-04-01

    The universal altimetry toolbox, BRAT (Broadview Radar Altimetry Toolbox) which can read all previous and current altimetry missions' data, incorporates now the capability to read the upcoming Sentinel3 L1 and L2 products. ESA endeavoured to develop and supply this capability to support the users of the future Sentinel3 SAR Altimetry Mission. BRAT is a collection of tools and tutorial documents designed to facilitate the processing of radar altimetry data. This project started in 2005 from the joint efforts of ESA (European Space Agency) and CNES (Centre National d'Etudes Spatiales), and it is freely available at http://earth.esa.int/brat. The tools enable users to interact with the most common altimetry data formats. The BratGUI is the frontend for the powerful command line tools that are part of the BRAT suite. BRAT can also be used in conjunction with MATLAB/IDL (via reading routines) or in C/C++/Fortran via a programming API, allowing the user to obtain desired data, bypassing the dataformatting hassle. BRAT can be used simply to visualise data quickly, or to translate the data into other formats such as NetCDF, ASCII text files, KML (Google Earth) and raster images (JPEG, PNG, etc.). Several kinds of computations can be done within BRAT involving combinations of data fields that the user can save for posterior reuse or using the already embedded formulas that include the standard oceanographic altimetry formulas. The Radar Altimeter Tutorial, that contains a strong introduction to altimetry, shows its applications in different fields such as Oceanography, Cryosphere, Geodesy, Hydrology among others. Included are also "use cases", with step-by-step examples, on how to use the toolbox in the different contexts. The Sentinel3 SAR Altimetry Toolbox shall benefit from the current BRAT version. While developing the toolbox we will revamp of the Graphical User Interface and provide, among other enhancements, support for reading the upcoming S3 datasets and specific

  13. Doppler radar flowmeter

    Science.gov (United States)

    Petlevich, Walter J.; Sverdrup, Edward F.

    1978-01-01

    A Doppler radar flowmeter comprises a transceiver which produces an audio frequency output related to the Doppler shift in frequency between radio waves backscattered from particulate matter carried in a fluid and the radiated radio waves. A variable gain amplifier and low pass filter are provided for amplifying and filtering the transceiver output. A frequency counter having a variable triggering level is also provided to determine the magnitude of the Doppler shift. A calibration method is disclosed wherein the amplifier gain and frequency counter trigger level are adjusted to achieve plateaus in the output of the frequency counter and thereby allow calibration without the necessity of being able to visually observe the flow.

  14. Radar Imaging of Stationary and Moving Targets

    Science.gov (United States)

    2012-06-28

    Sciences Research Institute. Member of Organizing Committee for introductory workshop at MSRI • June 14-18, 2010, arranged for AFRL (Matt Ferrara ) to...Schneible, Vincent Amuso, SciTech Publishing, Inc., 2010. 2. K. Voccola, B. Yazici, M. Ferrara , and M. Cheney, “On the relationship between the generalized...echo imaging using distributed apertures in multi-path,” IEEE Radar Conference, May, 2008, Rome, Italy . 14 10. “Wideband pulse-echo imaging using

  15. Imaging with Synthetic Aperture Radar

    CERN Document Server

    Massonnet, Didier

    2008-01-01

    Describing a field that has been transformed by the recent availability of data from a new generation of space and airborne systems, the authors offer a synthetic geometrical approach to the description of synthetic aperture radar, one that addresses physicists, radar specialists, as well as experts in image processing.  

  16. Terahertz radar cross section measurements

    DEFF Research Database (Denmark)

    Iwaszczuk, Krzysztof; Heiselberg, Henning; Jepsen, Peter Uhd

    2010-01-01

    We perform angle- and frequency-resolved radar cross section (RCS) measurements on objects at terahertz frequencies. Our RCS measurements are performed on a scale model aircraft of size 5-10 cm in polar and azimuthal configurations, and correspond closely to RCS measurements with conventional radar...

  17. Performance indicators modern surveillance radar

    NARCIS (Netherlands)

    Nooij, P.N.C.; Theil, A.

    2014-01-01

    Blake chart computations are widely employed to rank detection coverage capabilities of competitive search radar systems. Developed for comparable 2D radar systems with a mechanically rotating reflector antenna, it was not necessary to regard update rate and plot quality in Blake's chart. To

  18. Ground Penetrating Radar Technologies in Ukraine

    Science.gov (United States)

    Pochanin, Gennadiy P.; Masalov, Sergey A.

    2014-05-01

    Transient electromagnetic fields are of great interest in Ukraine. The following topics are studied by research teams, with high-level achievements all over the world: (i) Ultra-Wide Band/Short-pulse radar techniques (IRE and LLC "Transient Technologies", for more information please visit http://applied.ire.kharkov.ua/radar%20systems_their%20components%20and%20relevant%20technologies_e.html and http://viy.ua); (ii) Ground Penetrating Radar (GPR) with stepped frequency sounding signals (IRE); (iii) Continuous-Wave (CW) radar with phase-shift keying signals (IRE); and (iv) Radio-wave interference investigation (Scientific and Technical Centre of The Subsurface Investigation, http://geophysics.ua). GPR applications are mainly in search works, for example GPR is often used to search for treasures. It is also used to identify leaks and diffusion of petroleum in soil, in storage areas, as well as for fault location of pipelines. Furthermore, GPR is used for the localization of underground utilities and for diagnostics of the technical state of hydro dams. Deeper GPR probing was performed to identify landslides in Crimea. Rescue radar with CW signal was designed in IRE to search for living people trapped under the rubble of collapsed buildings. The fourth version of this radar has been recently created, showing higher stability and noise immunity. Radio-wave interference investigation allows studying the soil down to tens of meters. It is possible to identify areas with increased conductivity (moisture) of the soil. LLC "Transient Technologies" is currently working with Shevchenko Kyiv University on a cooperation program in which the construction of a test site is one of the planned tasks. In the framework of this program, a GPR with a 300 MHz antenna was handed to the geological Faculty of the University. Employees of "Transient Technologies" held introductory lectures with a practical demonstration for students majoring in geophysics. The authors participated to GPR

  19. Detection of Weather Radar Clutter

    DEFF Research Database (Denmark)

    Bøvith, Thomas

    2008-01-01

    classification and use a range of different techniques and input data. The first method uses external information from multispectral satellite images to detect clutter. The information in the visual, near-infrared, and infrared parts of the spectrum can be used to distinguish between cloud and cloud-free areas......Weather radars provide valuable information on precipitation in the atmosphere but due to the way radars work, not only precipitation is observed by the weather radar. Weather radar clutter, echoes from non-precipitating targets, occur frequently in the data, resulting in lowered data quality....... Especially in the application of weather radar data in quantitative precipitation estimation and forecasting a high data quality is important. Clutter detection is one of the key components in achieving this goal. This thesis presents three methods for detection of clutter. The methods use supervised...

  20. 18th International Laser Radar Conference

    CERN Document Server

    Neuber, Roland; Rairoux, Patrick; Wandinger, Ulla

    1997-01-01

    Lidar or laser radar, the depth-resolved remote measurement of atmospheric parameters with optical means, has become an important tool in the field of atmospheric and environmental remote sensing. In this volume the latest progress in the development of lidar methods, experiments, and applications is described. The content is based on selected and thoroughly refereed papers presented at the 18th International Laser Radar Conference, Berlin, 22-26 July 1996. The book is divided into six parts which cover the topics of tropospheric aerosols and clouds, lidar in space, wind, water vapor, troposheric trace gases and plumes, and stratospheric and mesospheric profiling. As a supplement to fundamental lidar textbooks this volume may serve as a guide for scientists, engineers, and graduate students through the blossoming field of modern lidar techniques and their contribution to atmospheric and environmental research.

  1. Updating river basin models with radar altimetry

    DEFF Research Database (Denmark)

    Michailovsky, Claire Irene B.

    suited for use in data assimilation frameworks which combine the information content from models and current observations to produce improved forecasts and reduce prediction uncertainty. The focus of the second and third papers of this thesis was therefore the use of radar altimetry as update data...... of political unwillingness to share data which is a common problem in particular in transboundary settings. In this context, remote sensing (RS) datasets provide an appealing alternative to traditional in-situ data and much research effort has gone into the use of these datasets for hydrological applications...... response of a catchment to meteorological forcing. While river discharge cannot be directly measured from space, radar altimetry (RA) can measure water level variations in rivers at the locations where the satellite ground track and river network intersect called virtual stations or VS. In this PhD study...

  2. Interception of LPI radar signals

    Science.gov (United States)

    Lee, Jim P.

    1991-11-01

    Most current radars are designed to transmit short duration pulses with relatively high peak power. These radars can be detected easily by the use of relatively modest EW intercept receivers. Three radar functions (search, anti-ship missile (ASM) seeker, and navigation) are examined to evaluate the effectiveness of potential low probability of intercept (LPI) techniques, such as waveform coding, antenna profile control, and power management that a radar may employ against current Electronic Warfare (EW) receivers. The general conclusion is that it is possible to design a LPI radar which is effective against current intercept EW receivers. LPI operation is most easily achieved at close ranges and against a target with a large radar cross section. The general system sensitivity requirement for the detection of current and projected LPI radars is found to be on the order of -100 dBmi which cannot be met by current EW receivers. Finally, three potential LPI receiver architectures, using channelized, superhet, and acousto-optic receivers with narrow RF and video bandwidths are discussed. They have shown some potential in terms of providing the sensitivity and capability in an environment where both conventional and LPI signals are present.

  3. Space Radar Image of Harvard Forest

    Science.gov (United States)

    1999-01-01

    This is a radar image of the area surrounding the Harvard Forest in north-central Massachusetts that has been operated as a ecological research facility by Harvard University since 1907. At the center of the image is the Quabbin Reservoir, and the Connecticut River is at the lower left of the image. The Harvard Forest itself is just above the reservoir. Researchers are comparing the naturally occurring physical disturbances in the forest and the recent and projected chemical disturbances and their effects on the forest ecosystem. Agricultural land appears dark blue/purple, along with low shrub vegetation and some wetlands. Urban development is bright pink; the yellow to green tints are conifer-dominated vegetation with the pitch pine sand plain at the middle left edge of the image appearing very distinctive. The green tint may indicate pure pine plantation stands, and deciduous broadleaf trees appear gray/pink with perhaps wetter sites being pinker. This image was acquired by the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) aboard the space shuttle Endeavour. SIR-C/X-SAR, a joint mission of the German, Italian and the United States space agencies, is part of NASA's Mission to Planet Earth. The image is centered at 42.50 degrees North latitude and 72.33 degrees West longitude and covers an area of 53 kilometers 63 by kilometers (33 miles by 39 miles). The colors in the image are assigned to different frequencies and polarizations of the radar as follows: red is L-band horizontally transmitted and horizontally received; green is L-band horizontally transmitted and vertically received; and blue is C-band horizontally transmitted and horizontally received.

  4. Radar signal analysis and processing using Matlab

    CERN Document Server

    Mahafza, Bassem R

    2008-01-01

    Offering radar-related software for the analysis and design of radar waveform and signal processing, this book provides comprehensive coverage of radar signals and signal processing techniques and algorithms. It contains numerous graphical plots, common radar-related functions, table format outputs, and end-of-chapter problems. The complete set of MATLAB[registered] functions and routines are available for download online.

  5. The use of radar for bathymetry assessment

    NARCIS (Netherlands)

    Aardoom, J.H.; Greidanus, H.S.F.

    1998-01-01

    The bottom topography in shallow seas can be observed by air- and spaceborne imaging radar. Bathymetric information derived from radar data is limited in accuracy, but radar has a good spatial coverage. The accuracy can be increased by assimilating the radar imagery into existing or insitu gathered

  6. Propagation of radar rainfall uncertainty in urban flood simulations

    Science.gov (United States)

    Liguori, Sara; Rico-Ramirez, Miguel

    2013-04-01

    This work discusses the results of the implementation of a novel probabilistic system designed to improve ensemble sewer flow predictions for the drainage network of a small urban area in the North of England. The probabilistic system has been developed to model the uncertainty associated to radar rainfall estimates and propagate it through radar-based ensemble sewer flow predictions. The assessment of this system aims at outlining the benefits of addressing the uncertainty associated to radar rainfall estimates in a probabilistic framework, to be potentially implemented in the real-time management of the sewer network in the study area. Radar rainfall estimates are affected by uncertainty due to various factors [1-3] and quality control and correction techniques have been developed in order to improve their accuracy. However, the hydrological use of radar rainfall estimates and forecasts remains challenging. A significant effort has been devoted by the international research community to the assessment of the uncertainty propagation through probabilistic hydro-meteorological forecast systems [4-5], and various approaches have been implemented for the purpose of characterizing the uncertainty in radar rainfall estimates and forecasts [6-11]. A radar-based ensemble stochastic approach, similar to the one implemented for use in the Southern-Alps by the REAL system [6], has been developed for the purpose of this work. An ensemble generator has been calibrated on the basis of the spatial-temporal characteristics of the residual error in radar estimates assessed with reference to rainfall records from around 200 rain gauges available for the year 2007, previously post-processed and corrected by the UK Met Office [12-13]. Each ensemble member is determined by summing a perturbation field to the unperturbed radar rainfall field. The perturbations are generated by imposing the radar error spatial and temporal correlation structure to purely stochastic fields. A

  7. Radar observations of asteroids

    International Nuclear Information System (INIS)

    Ostro, S.J.

    1989-01-01

    This paper describes echoes from 33 main-belt asteroids (MBAs) and 19 near-Earth asteroids (NEAs) have provided a wealth of new information about these objects such as sizes, shapes, spin vectors, and such surface characteristics as decimeter-scale morphology, topographic relief, regolith porosity and metal concentrations. On average, small NEAs are much rougher at decimeter scales than MBAs, comets or terrestrial planets. Some of the largest MBAs (e.g., 1 Ceres and 2 Pallas ) are smoother than the moon at decimeter scales but much rougher than the Moon at some much larger scale. There is at least a five-fold variation in the radar albedos of MBAs, implying substantial variations in the surface porosities or metal concentrations of these objects. The highest MBA albedo estimate, for 16 Psyche, is consistent with a metal concentration near unity and lunar porosities

  8. Material integrity verification radar

    International Nuclear Information System (INIS)

    Koppenjan, S.K.

    1999-01-01

    The International Atomic Energy Agency (IAEA) has the need for verification of 'as-built' spent fuel-dry storage containers and other concrete structures. The IAEA has tasked the Special Technologies Laboratory (STL) to fabricate, test, and deploy a stepped-frequency Material Integrity Verification Radar (MIVR) system to nondestructively verify the internal construction of these containers. The MIVR system is based on previously deployed high-frequency, ground penetrating radar (GPR) systems that have been developed by STL for the U.S. Department of Energy (DOE). Whereas GPR technology utilizes microwave radio frequency energy to create subsurface images, MTVR is a variation for which the medium is concrete instead of soil. The purpose is to nondestructively verify the placement of concrete-reinforcing materials, pipes, inner liners, and other attributes of the internal construction. The MIVR system underwent an initial field test on CANDU reactor spent fuel storage canisters at Atomic Energy of Canada Limited (AECL), Chalk River Laboratories, Ontario, Canada, in October 1995. A second field test at the Embalse Nuclear Power Plant in Embalse, Argentina, was completed in May 1996. The DOE GPR also was demonstrated at the site. Data collection and analysis were performed for the Argentine National Board of Nuclear Regulation (ENREN). IAEA and the Brazilian-Argentine Agency for the Control and Accounting of Nuclear Material (ABACC) personnel were present as observers during the test. Reinforcing materials were evident in the color, two-dimensional images produced by the MIVR system. A continuous pattern of reinforcing bars was evident and accurate estimates on the spacing, depth, and size were made. The potential uses for safeguard applications were jointly discussed. The MIVR system, as successfully demonstrated in the two field tests, can be used as a design verification tool for IAEA safeguards. A deployment of MIVR for Design Information Questionnaire (DIQ

  9. Signal processing in noise waveform radar

    CERN Document Server

    Kulpa, Krzysztof

    2013-01-01

    This book is devoted to the emerging technology of noise waveform radar and its signal processing aspects. It is a new kind of radar, which use noise-like waveform to illuminate the target. The book includes an introduction to basic radar theory, starting from classical pulse radar, signal compression, and wave radar. The book then discusses the properties, difficulties and potential of noise radar systems, primarily for low-power and short-range civil applications. The contribution of modern signal processing techniques to making noise radar practical are emphasized, and application examples

  10. Introduction to radar target recognition

    CERN Document Server

    Tait, P

    2006-01-01

    This new text provides an overview of the radar target recognition process and covers the key techniques being developed for operational systems. It is based on the fundamental scientific principles of high resolution radar, and explains how the techniques can be used in real systems, taking into account the characteristics of practical radar system designs and component limitations. It also addresses operational aspects, such as how high resolution modes would fit in with other functions such as detection and tracking. Mathematics is kept to a minimum and the complex techniques and issues are

  11. Study on the shipboard radar reconnaissance equipment azimuth benchmark method

    Science.gov (United States)

    Liu, Zhenxing; Jiang, Ning; Ma, Qian; Liu, Songtao; Wang, Longtao

    2015-10-01

    The future naval battle will take place in a complex electromagnetic environment. Therefore, seizing the electromagnetic superiority has become the major actions of the navy. Radar reconnaissance equipment is an important part of the system to obtain and master battlefield electromagnetic radiation source information. Azimuth measurement function is one of the main function radar reconnaissance equipments. Whether the accuracy of direction finding meets the requirements, determines the vessels successful or not active jamming, passive jamming, guided missile attack and other combat missions, having a direct bearing on the vessels combat capabilities . How to test the performance of radar reconnaissance equipment, while affecting the task as little as possible is a problem. This paper, based on radar signal simulator and GPS positioning equipment, researches and experiments on one new method, which povides the azimuth benchmark required by the direction-finding precision test anytime anywhere, for the ships at jetty to test radar reconnaissance equipment performance in direction-finding. It provides a powerful means for the naval radar reconnaissance equipments daily maintenance and repair work[1].

  12. Informational analysis for compressive sampling in radar imaging.

    Science.gov (United States)

    Zhang, Jingxiong; Yang, Ke

    2015-03-24

    Compressive sampling or compressed sensing (CS) works on the assumption of the sparsity or compressibility of the underlying signal, relies on the trans-informational capability of the measurement matrix employed and the resultant measurements, operates with optimization-based algorithms for signal reconstruction and is thus able to complete data compression, while acquiring data, leading to sub-Nyquist sampling strategies that promote efficiency in data acquisition, while ensuring certain accuracy criteria. Information theory provides a framework complementary to classic CS theory for analyzing information mechanisms and for determining the necessary number of measurements in a CS environment, such as CS-radar, a radar sensor conceptualized or designed with CS principles and techniques. Despite increasing awareness of information-theoretic perspectives on CS-radar, reported research has been rare. This paper seeks to bridge the gap in the interdisciplinary area of CS, radar and information theory by analyzing information flows in CS-radar from sparse scenes to measurements and determining sub-Nyquist sampling rates necessary for scene reconstruction within certain distortion thresholds, given differing scene sparsity and average per-sample signal-to-noise ratios (SNRs). Simulated studies were performed to complement and validate the information-theoretic analysis. The combined strategy proposed in this paper is valuable for information-theoretic orientated CS-radar system analysis and performance evaluation.

  13. Evaluation of turbulent dissipation rate retrievals from Doppler Cloud Radar

    Directory of Open Access Journals (Sweden)

    M. D. Shupe

    2012-06-01

    Full Text Available Turbulent dissipation rate retrievals from cloud radar Doppler velocity measurements are evaluated using independent, in situ observations in Arctic stratocumulus clouds. In situ validation data sets of dissipation rate are derived using sonic anemometer measurements from a tethered balloon and high frequency pressure variation observations from a research aircraft, both flown in proximity to stationary, ground-based radars. Modest biases are found among the data sets in particularly low- or high-turbulence regimes, but in general the radar-retrieved values correspond well with the in situ measurements. Root mean square differences are typically a factor of 4–6 relative to any given magnitude of dissipation rate. These differences are no larger than those found when comparing dissipation rates computed from tethered-balloon and meteorological tower-mounted sonic anemometer measurements made at spatial distances of a few hundred meters. Temporal lag analyses suggest that approximately half of the observed differences are due to spatial sampling considerations, such that the anticipated radar-based retrieval uncertainty is on the order of a factor of 2–3. Moreover, radar retrievals are clearly able to capture the vertical dissipation rate structure observed by the in situ sensors, while offering substantially more information on the time variability of turbulence profiles. Together these evaluations indicate that radar-based retrievals can, at a minimum, be used to determine the vertical structure of turbulence in Arctic stratocumulus clouds.

  14. Classification and correction of the radar bright band with polarimetric radar

    Science.gov (United States)

    Hall, Will; Rico-Ramirez, Miguel; Kramer, Stefan

    2015-04-01

    The annular region of enhanced radar reflectivity, known as the Bright Band (BB), occurs when the radar beam intersects a layer of melting hydrometeors. Radar reflectivity is related to rainfall through a power law equation and so this enhanced region can lead to overestimations of rainfall by a factor of up to 5, so it is important to correct for this. The BB region can be identified by using several techniques including hydrometeor classification and freezing level forecasts from mesoscale meteorological models. Advances in dual-polarisation radar measurements and continued research in the field has led to increased accuracy in the ability to identify the melting snow region. A method proposed by Kitchen et al (1994), a form of which is currently used operationally in the UK, utilises idealised Vertical Profiles of Reflectivity (VPR) to correct for the BB enhancement. A simpler and more computationally efficient method involves the formation of an average VPR from multiple elevations for correction that can still cause a significant decrease in error (Vignal 2000). The purpose of this research is to evaluate a method that relies only on analysis of measurements from an operational C-band polarimetric radar without the need for computationally expensive models. Initial results show that LDR is a strong classifier of melting snow with a high Critical Success Index of 97% when compared to the other variables. An algorithm based on idealised VPRs resulted in the largest decrease in error when BB corrected scans are compared to rain gauges and to lower level scans with a reduction in RMSE of 61% for rain-rate measurements. References Kitchen, M., R. Brown, and A. G. Davies, 1994: Real-time correction of weather radar data for the effects of bright band, range and orographic growth in widespread precipitation. Q.J.R. Meteorol. Soc., 120, 1231-1254. Vignal, B. et al, 2000: Three methods to determine profiles of reflectivity from volumetric radar data to correct

  15. ARM Cloud Radar Simulator Package for Global Climate Models Value-Added Product

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yuying [North Carolina State Univ., Raleigh, NC (United States); Xie, Shaocheng [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-05-01

    It has been challenging to directly compare U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility ground-based cloud radar measurements with climate model output because of limitations or features of the observing processes and the spatial gap between model and the single-point measurements. To facilitate the use of ARM radar data in numerical models, an ARM cloud radar simulator was developed to converts model data into pseudo-ARM cloud radar observations that mimic the instrument view of a narrow atmospheric column (as compared to a large global climate model [GCM] grid-cell), thus allowing meaningful comparison between model output and ARM cloud observations. The ARM cloud radar simulator value-added product (VAP) was developed based on the CloudSat simulator contained in the community satellite simulator package, the Cloud Feedback Model Intercomparison Project (CFMIP) Observation Simulator Package (COSP) (Bodas-Salcedo et al., 2011), which has been widely used in climate model evaluation with satellite data (Klein et al., 2013, Zhang et al., 2010). The essential part of the CloudSat simulator is the QuickBeam radar simulator that is used to produce CloudSat-like radar reflectivity, but is capable of simulating reflectivity for other radars (Marchand et al., 2009; Haynes et al., 2007). Adapting QuickBeam to the ARM cloud radar simulator within COSP required two primary changes: one was to set the frequency to 35 GHz for the ARM Ka-band cloud radar, as opposed to 94 GHz used for the CloudSat W-band radar, and the second was to invert the view from the ground to space so as to attenuate the beam correctly. In addition, the ARM cloud radar simulator uses a finer vertical resolution (100 m compared to 500 m for CloudSat) to resolve the more detailed structure of clouds captured by the ARM radars. The ARM simulator has been developed following the COSP workflow (Figure 1) and using the capabilities available in COSP

  16. Radar spectrum opportunities for cognitive communications transmission

    OpenAIRE

    Wang, L; McGeehan, JP; Williams, C; Doufexi, A

    2008-01-01

    In relation to opportunistic access to radar spectrum, the impact of the radar on a communication system is investigated in this paper. This paper illustrates that by exploring the spatial and temporal opportunities in the radar spectrum and therefore improving the tolerance level to radar interference, a substantial increase on the throughput of a communication system is possible. Results are presented regarding the impact of swept radars on a WiMAX system. The results show the impact of SIR...

  17. Digital Beamforming Synthetic Aperture Radar Developments at NASA Goddard Space Flight Center

    Science.gov (United States)

    Rincon, Rafael; Fatoyinbo, Temilola; Osmanoglu, Batuhan; Lee, Seung Kuk; Du Toit, Cornelis F.; Perrine, Martin; Ranson, K. Jon; Sun, Guoqing; Deshpande, Manohar; Beck, Jaclyn; hide

    2016-01-01

    Advanced Digital Beamforming (DBF) Synthetic Aperture Radar (SAR) technology is an area of research and development pursued at the NASA Goddard Space Flight Center (GSFC). Advanced SAR architectures enhances radar performance and opens a new set of capabilities in radar remote sensing. DBSAR-2 and EcoSAR are two state-of-the-art radar systems recently developed and tested. These new instruments employ multiple input-multiple output (MIMO) architectures characterized by multi-mode operation, software defined waveform generation, digital beamforming, and configurable radar parameters. The instruments have been developed to support several disciplines in Earth and Planetary sciences. This paper describes the radars advanced features and report on the latest SAR processing and calibration efforts.

  18. TERRESTRIAL AND AERIAL GROUND-PENETRATING RADAR IN USE FOR THE ARCHITECTURAL RESEARCHES: ANCIENT 16TH CENTURY WATER SUPPLY AND DRAINAGE AT THE MONASTERY OF EL ESCORIAL (MADRID, SPAIN

    Directory of Open Access Journals (Sweden)

    P. Chias

    2013-07-01

    Full Text Available Remote sensing techniques in Archaeology are increasingly essential components of the methodologies used in archaeological and architectural researches. They allow uncovering unique forgotten data which are unobtainable using traditional excavation techniques, mainly because their precise location is lost. These data are still important since they can help to prevent flood effects inside the ancient building cellars and basements, as it happened periodically in El Escorial. Wide ancient drainage galleries run more than one hundred feet downhill outside the building, ensuring that rainwater and springs were adequately drained. Nowadays their plans are lost, and the lack of documents related both to the ancient water supply and drainage systems become an impediment to solve the stains of damp on the stone masonry walls and vaults, and even other occasional flooding effects. In this case, nondestructive techniques were needed to find the ancient underground passages in order to preserve the integrity of the building and its current activities. At a first stage oblique aerial infrared images taken from a helium barrage balloon helped to find easily, quickly and cheaply the buried masonry structures. Secondly, radar pulses were particularly interesting to image the subsurface as they were valuable means of assessing the presence and amount of both soil water and buried structures. The combination of both techniques proved to be an accurate and low-cost way to find the ancient drainage systems. Finally, results were produced by means of open source software.

  19. Ambiguity Function and Resolution Characteristic Analysis of DVB-S Signal for Passive Radar

    Directory of Open Access Journals (Sweden)

    Jin Wei

    2012-12-01

    Full Text Available This paper gives the performance research on the ambiguity function and resolution of passive radar based on DVB-S (Digital Video Broadcasting-Satellite signal. The radar system structure and signal model of DVB-S signal are firstly studied, then the ambiguity function of DVB-S signal is analyzed. At last, it has been obtained how the bistatic radar position impacts the resolution. Theoretical analyses and computer simulation show that DVB-S signal is applicable as an illuminator for passive radar.

  20. Solid-state radar switchboard

    Science.gov (United States)

    Thiebaud, P.; Cross, D. C.

    1980-07-01

    A new solid-state radar switchboard equipped with 16 input ports which will output data to 16 displays is presented. Each of the ports will handle a single two-dimensional radar input, or three ports will accommodate a three-dimensional radar input. A video switch card of the switchboard is used to switch all signals, with the exception of the IFF-mode-control lines. Each card accepts inputs from up to 16 sources and can pass a signal with bandwidth greater than 20 MHz to the display assigned to that card. The synchro amplifier of current systems has been eliminated and in the new design each PPI receives radar data via a single coaxial cable. This significant reduction in cabling is achieved by adding a serial-to-parallel interface and a digital-to-synchro converter located at the PPI.

  1. SMAP RADAR Calibration and Validation

    Science.gov (United States)

    West, R. D.; Jaruwatanadilok, S.; Chaubel, M. J.; Spencer, M.; Chan, S. F.; Chen, C. W.; Fore, A.

    2015-12-01

    The Soil Moisture Active Passive (SMAP) mission launched on Jan 31, 2015. The mission employs L-band radar and radiometer measurements to estimate soil moisture with 4% volumetric accuracy at a resolution of 10 km, and freeze-thaw state at a resolution of 1-3 km. Immediately following launch, there was a three month instrument checkout period, followed by six months of level 1 (L1) calibration and validation. In this presentation, we will discuss the calibration and validation activities and results for the L1 radar data. Early SMAP radar data were used to check commanded timing parameters, and to work out issues in the low- and high-resolution radar processors. From April 3-13 the radar collected receive only mode data to conduct a survey of RFI sources. Analysis of the RFI environment led to a preferred operating frequency. The RFI survey data were also used to validate noise subtraction and scaling operations in the radar processors. Normal radar operations resumed on April 13. All radar data were examined closely for image quality and calibration issues which led to improvements in the radar data products for the beta release at the end of July. Radar data were used to determine and correct for small biases in the reported spacecraft attitude. Geo-location was validated against coastline positions and the known positions of corner reflectors. Residual errors at the time of the beta release are about 350 m. Intra-swath biases in the high-resolution backscatter images are reduced to less than 0.3 dB for all polarizations. Radiometric cross-calibration with Aquarius was performed using areas of the Amazon rain forest. Cross-calibration was also examined using ocean data from the low-resolution processor and comparing with the Aquarius wind model function. Using all a-priori calibration constants provided good results with co-polarized measurements matching to better than 1 dB, and cross-polarized measurements matching to about 1 dB in the beta release. During the

  2. ASSIMILATION OF DOPPLER RADAR DATA INTO NUMERICAL WEATHER MODELS

    Energy Technology Data Exchange (ETDEWEB)

    Chiswell, S.; Buckley, R.

    2009-01-15

    During the year 2008, the United States National Weather Service (NWS) completed an eight fold increase in sampling capability for weather radars to 250 m resolution. This increase is expected to improve warning lead times by detecting small scale features sooner with increased reliability; however, current NWS operational model domains utilize grid spacing an order of magnitude larger than the radar data resolution, and therefore the added resolution of radar data is not fully exploited. The assimilation of radar reflectivity and velocity data into high resolution numerical weather model forecasts where grid spacing is comparable to the radar data resolution was investigated under a Laboratory Directed Research and Development (LDRD) 'quick hit' grant to determine the impact of improved data resolution on model predictions with specific initial proof of concept application to daily Savannah River Site operations and emergency response. Development of software to process NWS radar reflectivity and radial velocity data was undertaken for assimilation of observations into numerical models. Data values within the radar data volume undergo automated quality control (QC) analysis routines developed in support of this project to eliminate empty/missing data points, decrease anomalous propagation values, and determine error thresholds by utilizing the calculated variances among data values. The Weather Research and Forecasting model (WRF) three dimensional variational data assimilation package (WRF-3DVAR) was used to incorporate the QC'ed radar data into input and boundary conditions. The lack of observational data in the vicinity of SRS available to NWS operational models signifies an important data void where radar observations can provide significant input. These observations greatly enhance the knowledge of storm structures and the environmental conditions which influence their development. As the increase in computational power and availability has

  3. Ground Penetrating Radar Imaging of Buried Metallic Objects

    DEFF Research Database (Denmark)

    Polat, A. Burak; Meincke, Peter

    2001-01-01

    During the past decade there has been considerable research on ground penetrating radar (GPR) tomography for detecting objects such as pipes, cables, mines and barrels buried under the surface of the Earth. While the earlier researches were all based on the assumption of a homogeneous background...

  4. An Overview of Radar Waveform Optimization for Target Detection

    Directory of Open Access Journals (Sweden)

    Wang Lulu

    2016-10-01

    Full Text Available An optimal waveform design method that fully employs the knowledge of the target and the environment can further improve target detection performance, thus is of vital importance to research. In this paper, methods of radar waveform optimization for target detection are reviewed and summarized and provide the basis for the research.

  5. Proposed satellite position determination systems and techniques for Geostationary Synthetic Aperture Radar

    OpenAIRE

    Martin Fuster, Roger; Fernández Usón, Marc; Casado Blanco, David; Broquetas Ibars, Antoni

    2016-01-01

    This paper proposes two different calibration techniques for Geostationary Synthetic Aperture Radar (GEOSAR) missions requiring a high precision positioning, based on Active Radar Calibrators and Ground Based Interferometry. The research is enclosed in the preparation studies of a future GEOSAR mission providing continuous monitoring at continental scale. Peer Reviewed

  6. 47 CFR 15.509 - Technical requirements for ground penetrating radars and wall imaging systems.

    Science.gov (United States)

    2010-10-01

    ..., fire fighting, emergency rescue, scientific research, commercial mining, or construction. (1) Parties... radars and wall imaging systems. 15.509 Section 15.509 Telecommunication FEDERAL COMMUNICATIONS... ground penetrating radars and wall imaging systems. (a) The UWB bandwidth of an imaging system operating...

  7. Performance test and verification of an off-the-shelf automated avian radar tracking system.

    Science.gov (United States)

    May, Roel; Steinheim, Yngve; Kvaløy, Pål; Vang, Roald; Hanssen, Frank

    2017-08-01

    Microwave radar is an important tool for observation of birds in flight and represents a tremendous increase in observation capability in terms of amount of surveillance space that can be covered at relatively low cost. Based on off-the-shelf radar hardware, automated radar tracking systems have been developed for monitoring avian movements. However, radar used as an observation instrument in biological research has its limitations that are important to be aware of when analyzing recorded radar data. This article describes a method for exploring the detection capabilities of a dedicated short-range avian radar system used inside the operational Smøla wind-power plant. The purpose of the testing described was to find the maximum detection range for various sized birds, while controlling for the effects of flight tortuosity, flight orientation relative to the radar and ground clutter. The method was to use a dedicated test target in form of a remotely controlled unmanned aerial vehicle (UAV) with calibrated radar cross section (RCS), which enabled the design of virtually any test flight pattern within the area of interest. The UAV had a detection probability of 0.5 within a range of 2,340 m from the radar. The detection performance obtained by the RCS-calibrated test target (-11 dBm 2 , 0.08 m 2 RCS) was then extrapolated to find the corresponding performance of differently sized birds. Detection range depends on system sensitivity, the environment within which the radar is placed and the spatial distribution of birds. The avian radar under study enables continuous monitoring of bird activity within a maximum range up to 2 km dependent on the size of the birds in question. While small bird species may be detected up to 0.5-1 km, larger species may be detected up to 1.5-2 km distance from the radar.

  8. Quantitative analysis of ground penetrating radar data in the Mu Us Sandland

    Science.gov (United States)

    Fu, Tianyang; Tan, Lihua; Wu, Yongqiu; Wen, Yanglei; Li, Dawei; Duan, Jinlong

    2018-06-01

    Ground penetrating radar (GPR), which can reveal the sedimentary structure and development process of dunes, is widely used to evaluate aeolian landforms. The interpretations for GPR profiles are mostly based on qualitative descriptions of geometric features of the radar reflections. This research quantitatively analyzed the waveform parameter characteristics of different radar units by extracting the amplitude and time interval parameters of GPR data in the Mu Us Sandland in China, and then identified and interpreted different sedimentary structures. The results showed that different types of radar units had specific waveform parameter characteristics. The main waveform parameter characteristics of sand dune radar facies and sandstone radar facies included low amplitudes and wide ranges of time intervals, ranging from 0 to 0.25 and 4 to 33 ns respectively, and the mean amplitudes changed gradually with time intervals. The amplitude distribution curves of various sand dune radar facies were similar as unimodal distributions. The radar surfaces showed high amplitudes with time intervals concentrated in high-value areas, ranging from 0.08 to 0.61 and 9 to 34 ns respectively, and the mean amplitudes changed drastically with time intervals. The amplitude and time interval values of lacustrine radar facies were between that of sand dune radar facies and radar surfaces, ranging from 0.08 to 0.29 and 11 to 30 ns respectively, and the mean amplitude and time interval curve was approximately trapezoidal. The quantitative extraction and analysis of GPR reflections could help distinguish various radar units and provide evidence for identifying sedimentary structure in aeolian landforms.

  9. Runoff Analysis Considering Orographical Features Using Dual Polarization Radar Rainfall

    Science.gov (United States)

    Noh, Hui-seong; Shin, Hyun-seok; Kang, Na-rae; Lee, Choong-Ke; Kim, Hung-soo

    2013-04-01

    Recently, the necessity for rainfall estimation and forecasting using the radar is being highlighted, due to the frequent occurrence of torrential rainfall resulting from abnormal changes of weather. Radar rainfall data represents temporal and spatial distributions properly and replace the existing rain gauge networks. It is also frequently applied in many hydrologic field researches. However, the radar rainfall data has an accuracy limitation since it estimates rainfall, by monitoring clouds and precipitation particles formed around the surface of the earth(1.5-3km above the surface) or the atmosphere. In a condition like Korea where nearly 70% of the land is covered by mountainous areas, there are lots of restrictions to use rainfall radar, because of the occurrence of beam blocking areas by topography. This study is aiming at analyzing runoff and examining the applicability of (R(Z), R(ZDR) and R(KDP)) provided by the Han River Flood Control Office(HRFCO) based on the basin elevation of Nakdong river watershed. For this purpose, the amount of radar rainfall of each rainfall event was estimated according to three sub-basins of Nakdong river watershed with the average basin elevation above 400m which are Namgang dam, Andong dam and Hapcheon dam and also another three sub-basins with the average basin elevation below 150m which are Waegwan, Changryeong and Goryeong. After runoff analysis using a distribution model, Vflo model, the results were reviewed and compared with the observed runoff. This study estimated the rainfall by using the radar-rainfall transform formulas, (R(Z), R(Z,ZDR) and R(Z,ZDR,KDP) for four stormwater events and compared the results with the point rainfall of the rain gauge. As the result, it was overestimated or underestimated, depending on rainfall events. Also, calculation indicates that the values from R(Z,ZDR) and R(Z,ZDR,KDP) relatively showed the most similar results. Moreover the runoff analysis using the estimated radar rainfall is

  10. Creating soil moisture maps based on radar satellite imagery

    Science.gov (United States)

    Hnatushenko, Volodymyr; Garkusha, Igor; Vasyliev, Volodymyr

    2017-10-01

    The presented work is related to a study of mapping soil moisture basing on radar data from Sentinel-1 and a test of adequacy of the models constructed on the basis of data obtained from alternative sources. Radar signals are reflected from the ground differently, depending on its properties. In radar images obtained, for example, in the C band of the electromagnetic spectrum, soils saturated with moisture usually appear in dark tones. Although, at first glance, the problem of constructing moisture maps basing on radar data seems intuitively clear, its implementation on the basis of the Sentinel-1 data on an industrial scale and in the public domain is not yet available. In the process of mapping, for verification of the results, measurements of soil moisture obtained from logs of the network of climate stations NOAA US Climate Reference Network (USCRN) were used. This network covers almost the entire territory of the United States. The passive microwave radiometers of Aqua and SMAP satellites data are used for comparing processing. In addition, other supplementary cartographic materials were used, such as maps of soil types and ready moisture maps. The paper presents a comparison of the effect of the use of certain methods of roughening the quality of radar data on the result of mapping moisture. Regression models were constructed showing dependence of backscatter coefficient values Sigma0 for calibrated radar data of different spatial resolution obtained at different times on soil moisture values. The obtained soil moisture maps of the territories of research, as well as the conceptual solutions about automation of operations of constructing such digital maps, are presented. The comparative assessment of the time required for processing a given set of radar scenes with the developed tools and with the ESA SNAP product was carried out.

  11. Imaging of concrete specimens using inverse synthetic aperture radar

    International Nuclear Information System (INIS)

    Rhim, Hong C.; Buyukozturk, Oral

    2000-01-01

    Radar Measurement results of laboratory size concrete specimens are presented in this paper. The purpose of this research work is to study various aspects of the radar method in an effort to develop an improved radar system for nondestructive testing of concrete structures. The radar system used for the study is an Inverse Synthetic Aperture Radar (ISAR), which is capable of transmitting microwaves at three different frequency ranges of 2-3.4, 3.4-5.8, and 8-12 GHz. Radar measurement setup is such that the radar is locates 14.4 m away from a concrete target to satisfy a far-field criterion. The concrete target is rotated for 20 degrees during the measurements for the generation of two-dimensional (cross-range) imagery. Concrete targets used for the measurements have the dimensions of 305 mm (width)x305 mm (height)x92 mm (thickness) with different inside configurations. Comparisons are made for dry and wet specimens, specimens with and without inclusions. Each specimen is made to model various situations that a concrete structure can have in reality. Results show that center frequency, frequency bandwidth, and polarization of the incident wave have different effects on identifying the thickness or inclusions inside concrete specimens. Results also suggest that a certain combination of measurement parameters is suitable for a specific application area. Thus, measurement parameters can be optimized for a specific problem. The findings are presented and discussed in details in the paper. Signal processing schemes implemented for imaging of the specimens are also discussed

  12. Sea Ice Movements from Synthetic Aperture Radar

    Science.gov (United States)

    1981-12-01

    correlating these components. B-l8 These correlations are also plotted in figure l1. 5.3.3.2 AUlications of the space correlation. The spatial...aperture radar. To appear in J. of Geophys. Res. Hastings, A. D. Jr., 1971. Surface climate of the Arctic Basin. Report ETL- TR-71-5, Earth Sciences Division...Administration Grant NA50-AA-D-00015, which was funded in part by the Global Atmospheric Research Program and the Office of Climate Dynarics, Divisic

  13. Borehole radar diffraction tomography

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Seong Jun; Kim, Jung Ho; Yi, Myeong Jong; Chung, Seung Hwan; Lee, Hee Il [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1997-12-01

    Tomography is widely used as imaging method for determining subsurface structure. Among the reconstruction algorithms for tomographic imaging, travel time tomography is almost applied to imaging subsurface. But isolated small body comparable with the wavelength could not be well recognized by travel time tomography. Other tomographic method are need to improve the imaging process. In the study of this year, diffraction tomography was investigated. The theory for diffraction tomography is based on the 1st-order Born approximation. Multisource holography, which is similar to Kirchihoff migration, is compared with diffraction tomography. To improve 1st-order Born diffraction tomography, two kinds of filter designed from multisource holography and 2-D green function, respectively, applied on the reconstructed image. The algorithm was tested for the numerical modeling data of which algorithm consists of the analytic computation of radar signal in transmitter and receiver regions and 2-D FDM scheme for the propagation of electromagnetic waves in media. The air-filled cavity model to show a typical diffraction pattern was applied to diffraction tomography imaging, and the result shows accurate location and area of cavity. But the calculated object function is not well matched the real object function, because the air-filled cavity model is not satisfied week scattered inhomogeneity for 1st born approximation, and the error term is included in estimating source wavelet from received signals. In spite of the object function error, the diffraction tomography assist for interpretation of subsurface as if conducted with travel time tomography. And the fracture model was tested, 1st born diffraction tomographic image is poor because of limited view angle coverage and violation of week scatter assumption, but the filtered image resolve the fracture somewhat better. The tested diffraction tomography image confirms effectiveness of filter for enhancing resolution. (author). 14

  14. Radar rainfall image repair techniques

    Directory of Open Access Journals (Sweden)

    Stephen M. Wesson

    2004-01-01

    Full Text Available There are various quality problems associated with radar rainfall data viewed in images that include ground clutter, beam blocking and anomalous propagation, to name a few. To obtain the best rainfall estimate possible, techniques for removing ground clutter (non-meteorological echoes that influence radar data quality on 2-D radar rainfall image data sets are presented here. These techniques concentrate on repairing the images in both a computationally fast and accurate manner, and are nearest neighbour techniques of two sub-types: Individual Target and Border Tracing. The contaminated data is estimated through Kriging, considered the optimal technique for the spatial interpolation of Gaussian data, where the 'screening effect' that occurs with the Kriging weighting distribution around target points is exploited to ensure computational efficiency. Matrix rank reduction techniques in combination with Singular Value Decomposition (SVD are also suggested for finding an efficient solution to the Kriging Equations which can cope with near singular systems. Rainfall estimation at ground level from radar rainfall volume scan data is of interest and importance in earth bound applications such as hydrology and agriculture. As an extension of the above, Ordinary Kriging is applied to three-dimensional radar rainfall data to estimate rainfall rate at ground level. Keywords: ground clutter, data infilling, Ordinary Kriging, nearest neighbours, Singular Value Decomposition, border tracing, computation time, ground level rainfall estimation

  15. Hydrologic applications of weather radar

    Science.gov (United States)

    Seo, Dong-Jun; Habib, Emad; Andrieu, Hervé; Morin, Efrat

    2015-12-01

    By providing high-resolution quantitative precipitation information (QPI), weather radars have revolutionized hydrology in the last two decades. With the aid of GIS technology, radar-based quantitative precipitation estimates (QPE) have enabled routine high-resolution hydrologic modeling in many parts of the world. Given the ever-increasing need for higher-resolution hydrologic and water resources information for a wide range of applications, one may expect that the use of weather radar will only grow. Despite the tremendous progress, a number of significant scientific, technological and engineering challenges remain to realize its potential. New challenges are also emerging as new areas of applications are discovered, explored and pursued. The purpose of this special issue is to provide the readership with some of the latest advances, lessons learned, experiences gained, and science issues and challenges related to hydrologic applications of weather radar. The special issue features 20 contributions on various topics which reflect the increasing diversity as well as the areas of focus in radar hydrology today. The contributions may be grouped as follows:

  16. Micro-Doppler Feature Extraction and Recognition Based on Netted Radar for Ballistic Targets

    Directory of Open Access Journals (Sweden)

    Feng Cun-qian

    2015-12-01

    Full Text Available This study examines the complexities of using netted radar to recognize and resolve ballistic midcourse targets. The application of micro-motion feature extraction to ballistic mid-course targets is analyzed, and the current status of application and research on micro-motion feature recognition is concluded for singlefunction radar networks such as low- and high-resolution imaging radar networks. Advantages and disadvantages of these networks are discussed with respect to target recognition. Hybrid-mode radar networks combine low- and high-resolution imaging radar and provide a specific reference frequency that is the basis for ballistic target recognition. Main research trends are discussed for hybrid-mode networks that apply micromotion feature extraction to ballistic mid-course targets.

  17. Extended Target Recognition in Cognitive Radar Networks

    Directory of Open Access Journals (Sweden)

    Xiqin Wang

    2010-11-01

    Full Text Available We address the problem of adaptive waveform design for extended target recognition in cognitive radar networks. A closed-loop active target recognition radar system is extended to the case of a centralized cognitive radar network, in which a generalized likelihood ratio (GLR based sequential hypothesis testing (SHT framework is employed. Using Doppler velocities measured by multiple radars, the target aspect angle for each radar is calculated. The joint probability of each target hypothesis is then updated using observations from different radar line of sights (LOS. Based on these probabilities, a minimum correlation algorithm is proposed to adaptively design the transmit waveform for each radar in an amplitude fluctuation situation. Simulation results demonstrate performance improvements due to the cognitive radar network and adaptive waveform design. Our minimum correlation algorithm outperforms the eigen-waveform solution and other non-cognitive waveform design approaches.

  18. German Radar Observation Shuttle Experiment (ROSE)

    Science.gov (United States)

    Sleber, A. J.; Hartl, P.; Haydn, R.; Hildebrandt, G.; Konecny, G.; Muehlfeld, R.

    1984-01-01

    The success of radar sensors in several different application areas of interest depends on the knowledge of the backscatter of radar waves from the targets of interest, the variance of these interaction mechanisms with respect to changing measurement parameters, and the determination of the influence of he measuring systems on the results. The incidence-angle dependency of the radar cross section of different natural targets is derived. Problems involved by the combination of data gained with different sensors, e.g., MSS-, TM-, SPOTand SAR-images are analyzed. Radar cross-section values gained with ground-based radar spectrometers and spaceborne radar imaging, and non-imaging scatterometers and spaceborne radar images from the same areal target are correlated. The penetration of L-band radar waves into vegetated and nonvegetated surfaces is analyzed.

  19. NOAA NEXt-Generation RADar (NEXRAD) Products

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset consists of Level III weather radar products collected from Next-Generation Radar (NEXRAD) stations located in the contiguous United States, Alaska,...

  20. MST radar data-base management

    Science.gov (United States)

    Wickwar, V. B.

    1983-01-01

    Data management for Mesospheric-Stratospheric-Tropospheric, (MST) radars is addressed. An incoherent-scatter radar data base is discussed in terms of purpose, centralization, scope, and nature of the data base management system.

  1. Design of multi-frequency CW radars

    CERN Document Server

    Jankiraman, Mohinder

    2007-01-01

    This book deals with the basic theory for design and analysis of Low Probability of Intercept (LPI) radar systems. The design of one such multi-frequency high resolution LPI radar, PANDORA, is covered.

  2. Modern approach to relativity theory (radar formulation)

    International Nuclear Information System (INIS)

    Strel'tsov, V.N.

    1991-01-01

    The main peculiarities of the radar formulation of the relativity theory are presented. This formulation operates with the retarded (light) distances and relativistic or radar length introduced on their basis. 21 refs.; 1 tab

  3. Meteor detection on ST (MST) radars

    International Nuclear Information System (INIS)

    Avery, S.K.

    1987-01-01

    The ability to detect radar echoes from backscatter due to turbulent irregularities of the radio refractive index in the clear atmosphere has lead to an increasing number of established mesosphere - stratosphere - troposphere (MST or ST) radars. Humidity and temperature variations are responsible for the echo in the troposphere and stratosphere and turbulence acting on electron density gradients provides the echo in the mesosphere. The MST radar and its smaller version, the ST radar, are pulsed Doppler radars operating in the VHF - UHF frequency range. These echoes can be used to determine upper atmosphere winds at little extra cost to the ST radar configuration. In addition, the meteor echoes can supplement mesospheric data from an MST radar. The detection techniques required on the ST radar for delineating meteor echo returns are described

  4. SAR Ambiguity Study for the Cassini Radar

    Science.gov (United States)

    Hensley, Scott; Im, Eastwood; Johnson, William T. K.

    1993-01-01

    The Cassini Radar's synthetic aperture radar (SAR) ambiguity analysis is unique with respect to other spaceborne SAR ambiguity analyses owing to the non-orbiting spacecraft trajectory, asymmetric antenna pattern, and burst mode of data collection. By properly varying the pointing, burst mode timing, and radar parameters along the trajectory this study shows that the signal-to-ambiguity ratio of better than 15 dB can be achieved for all images obtained by the Cassini Radar.

  5. Radar operation in a hostile electromagnetic environment

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter

    2014-03-01

    Radar ISR does not always involve cooperative or even friendly targets. An adversary has numerous techniques available to him to counter the effectiveness of a radar ISR sensor. These generally fall under the banner of jamming, spoofing, or otherwise interfering with the EM signals required by the radar sensor. Consequently mitigation techniques are prudent to retain efficacy of the radar sensor. We discuss in general terms a number of mitigation techniques.

  6. Radar reflection off extensive air showers

    CERN Document Server

    Stasielak, J; Bertaina, M; Blümer, J; Chiavassa, A; Engel, R; Haungs, A; Huege, T; Kampert, K -H; Klages, H; Kleifges, M; Krömer, O; Ludwig, M; Mathys, S; Neunteufel, P; Pekala, J; Rautenberg, J; Riegel, M; Roth, M; Salamida, F; Schieler, H; Šmída, R; Unger, M; Weber, M; Werner, F; Wilczyński, H; Wochele, J

    2012-01-01

    We investigate the possibility of detecting extensive air showers by the radar technique. Considering a bistatic radar system and different shower geometries, we simulate reflection of radio waves off the static plasma produced by the shower in the air. Using the Thomson cross-section for radio wave reflection, we obtain the time evolution of the signal received by the antennas. The frequency upshift of the radar echo and the power received are studied to verify the feasibility of the radar detection technique.

  7. Probability and information theory, with applications to radar

    CERN Document Server

    Woodward, P M; Higinbotham, W

    1964-01-01

    Electronics and Instrumentation, Second Edition, Volume 3: Probability and Information Theory with Applications to Radar provides information pertinent to the development on research carried out in electronics and applied physics. This book presents the established mathematical techniques that provide the code in which so much of the mathematical theory of electronics and radar is expressed.Organized into eight chapters, this edition begins with an overview of the geometry of probability distributions in which moments play a significant role. This text then examines the mathematical methods in

  8. Compressive sensing for urban radar

    CERN Document Server

    Amin, Moeness

    2014-01-01

    With the emergence of compressive sensing and sparse signal reconstruction, approaches to urban radar have shifted toward relaxed constraints on signal sampling schemes in time and space, and to effectively address logistic difficulties in data acquisition. Traditionally, these challenges have hindered high resolution imaging by restricting both bandwidth and aperture, and by imposing uniformity and bounds on sampling rates.Compressive Sensing for Urban Radar is the first book to focus on a hybrid of two key areas: compressive sensing and urban sensing. It explains how reliable imaging, tracki

  9. Wind Turbine Radar Cross Section

    Directory of Open Access Journals (Sweden)

    David Jenn

    2012-01-01

    Full Text Available The radar cross section (RCS of a wind turbine is a figure of merit for assessing its effect on the performance of electronic systems. In this paper, the fundamental equations for estimating the wind turbine clutter signal in radar and communication systems are presented. Methods of RCS prediction are summarized, citing their advantages and disadvantages. Bistatic and monostatic RCS patterns for two wind turbine configurations, a horizontal axis three-blade design and a vertical axis helical design, are shown. The unique electromagnetic scattering features, the effect of materials, and methods of mitigating wind turbine clutter are also discussed.

  10. Principles of modern radar advanced techniques

    CERN Document Server

    Melvin, William

    2012-01-01

    Principles of Modern Radar: Advanced Techniques is a professional reference for practicing engineers that provides a stepping stone to advanced practice with in-depth discussions of the most commonly used advanced techniques for radar design. It will also serve advanced radar academic and training courses with a complete set of problems for students as well as solutions for instructors.

  11. Efficient Ways to Learn Weather Radar Polarimetry

    Science.gov (United States)

    Cao, Qing; Yeary, M. B.; Zhang, Guifu

    2012-01-01

    The U.S. weather radar network is currently being upgraded with dual-polarization capability. Weather radar polarimetry is an interdisciplinary area of engineering and meteorology. This paper presents efficient ways to learn weather radar polarimetry through several basic and practical topics. These topics include: 1) hydrometeor scattering model…

  12. 46 CFR 184.404 - Radars.

    Science.gov (United States)

    2010-10-01

    ... within one mile of land must be fitted with a FCC Type Accepted general marine radar system for surface... Federal Communications Commission (FCC) type accepted general marine radar system for surface navigation... 46 Shipping 7 2010-10-01 2010-10-01 false Radars. 184.404 Section 184.404 Shipping COAST GUARD...

  13. Radar meteors range distribution model. IV. Ionization coefficient

    Czech Academy of Sciences Publication Activity Database

    Pecinová, Drahomíra; Pecina, Petr

    2008-01-01

    Roč. 38, č. 1 (2008), s. 12-20 ISSN 1335-1842 R&D Projects: GA ČR GA205/03/1405 Institutional research plan: CEZ:AV0Z10030501 Keywords : physics of meteors * radar meteors * range distribution Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  14. Towards Inverse Synthetic Aperture Radar (ISAR) for small sea vessels

    CSIR Research Space (South Africa)

    Abdul Gaffar, MY

    2006-12-01

    Full Text Available Aperture Radar (ISAR) for Small Sea Vessels M.Y. Abdul Gaffar Council for Scientific and Industrial Research University of Cape Town Slide 2 © CSIR 2006 www.csir.co.za What is ISAR? • Technique that produces cross range...

  15. Development of Antennas for Subsurface Radars within ACE

    DEFF Research Database (Denmark)

    Yarovoy, Alexander; Meincke, Peter; Dauvignac, Jean-Yves

    2007-01-01

    The paper gives an overview of the joint activities of the ACE-2 partners in the area of antennas for surface penetrating radar. Main areas of joint research and development are discussed and main results of joint activities are presented. Special attention is given to experimental verification...

  16. A Machine Learning-based Rainfall System for GPM Dual-frequency Radar

    Science.gov (United States)

    Tan, H.; Chandrasekar, V.; Chen, H.

    2017-12-01

    Precipitation measurement produced by the Global Precipitation Measurement (GPM) Dual-frequency Precipitation Radar (DPR) plays an important role in researching the water circle and forecasting extreme weather event. Compare with its predecessor - Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR), GRM DPR measures precipitation in two different frequencies (i.e., Ku and Ka band), which can provide detailed information on the microphysical properties of precipitation particles, quantify particle size distribution and quantitatively measure light rain and falling snow. This paper presents a novel Machine Learning system for ground-based and space borne radar rainfall estimation. The system first trains ground radar data for rainfall estimation using rainfall measurements from gauges and subsequently uses the ground radar based rainfall estimates to train GPM DPR data in order to get space based rainfall product. Therein, data alignment between space DPR and ground radar is conducted using the methodology proposed by Bolen and Chandrasekar (2013), which can minimize the effects of potential geometric distortion of GPM DPR observations. For demonstration purposes, rainfall measurements from three rain gauge networks near Melbourne, Florida, are used for training and validation purposes. These three gauge networks, which are located in Kennedy Space Center (KSC), South Florida Water Management District (SFL), and St. Johns Water Management District (STJ), include 33, 46, and 99 rain gauge stations, respectively. Collocated ground radar observations from the National Weather Service (NWS) Weather Surveillance Radar - 1988 Doppler (WSR-88D) in Melbourne (i.e., KMLB radar) are trained with the gauge measurements. The trained model is then used to derive KMLB radar based rainfall product, which is used to train GPM DPR data collected from coincident overpasses events. The machine learning based rainfall product is compared against the GPM standard products

  17. Universal Library for Building Radar Operator Interface

    Directory of Open Access Journals (Sweden)

    A. A. Karankevich

    2014-01-01

    Full Text Available The article contains the results of the development of a software library, used for building software interfaces for radars being developed in BMSTU Radioelectronic Technics Scientific and Research Institute. The library is a software application library written in C++ using Qt and OpenGL libraries.The article describes the requirements, that the library is supposed to meet, in particular — cross-platform capabilities and versatility of the solution. The data types, that library uses, are described. The description of theinterface elements developed is shown, and some pictures of their operation are given.The article shows the main interface elements used. They are: «Matrix» that shows twodimensional data, «Waterfall», that is used for time scanning of the parameter specified, and «Plan Position Indicator» that shows circular scan from surveillance radar without geometric distortions.The part «Library implementation» shows the example of radiolocation station interface, that was based on this library, used in the working model of ultrashortpulse radar. Some results of the operation of this interface are also shown. The experiment shows the system working with two people in the field. As people start to move, the system becomes capable of distinguishing moving targets and stationary surface. The article shows the system operation the same way as the system operator can see it through his interface.The conclusion contains brief results of the development, the sphere of application of the software, and the prospects of the further development of the library.

  18. Observation of snowfall with a low-power FM-CW K-band radar (Micro Rain Radar)

    Science.gov (United States)

    Kneifel, Stefan; Maahn, Maximilian; Peters, Gerhard; Simmer, Clemens

    2011-06-01

    Quantifying snowfall intensity especially under arctic conditions is a challenge because wind and snow drift deteriorate estimates obtained from both ground-based gauges and disdrometers. Ground-based remote sensing with active instruments might be a solution because they can measure well above drifting snow and do not suffer from flow distortions by the instrument. Clear disadvantages are, however, the dependency of e.g. radar returns on snow habit which might lead to similar large uncertainties. Moreover, high sensitivity radars are still far too costly to operate in a network and under harsh conditions. In this paper we compare returns from a low-cost, low-power vertically pointing FM-CW radar (Micro Rain Radar, MRR) operating at 24.1 GHz with returns from a 35.5 GHz cloud radar (MIRA36) for dry snowfall during a 6-month observation period at an Alpine station (Environmental Research Station Schneefernerhaus, UFS) at 2,650 m height above sea level. The goal was to quantify the potential and limitations of the MRR in relation to what is achievable by a cloud radar. The operational MRR procedures to derive standard radar variables like effective reflectivity factor ( Z e) or the mean Doppler velocity ( W) had to be modified for snowfall since the MRR was originally designed for rain observations. Since the radar returns from snowfall are weaker than from comparable rainfall, the behavior of the MRR close to its detection threshold has been analyzed and a method is proposed to quantify the noise level of the MRR based on clear sky observations. By converting the resulting MRR- Z e into 35.5 GHz equivalent Z e values, a remaining difference below 1 dBz with slightly higher values close to the noise threshold could be obtained. Due to the much higher sensitivity of MIRA36, the transition of the MRR from the true signal to noise can be observed, which agrees well with the independent clear sky noise estimate. The mean Doppler velocity differences between both radars

  19. Radioprotection and radar: practical aspects

    International Nuclear Information System (INIS)

    Pepersack, J.P.

    1979-01-01

    The author, on basis of his experience in radar-radioprotection, exposes the standard and security norms and recommendations to be applied for the preventive adapation of the work-areas as well as for the follow-up of the exposed workers. (author)

  20. Characterizing the degree of convective clustering using radar reflectivity and its application to evaluating model simulations

    Science.gov (United States)

    Cheng, W. Y.; Kim, D.; Rowe, A.; Park, S.

    2017-12-01

    Despite the impact of mesoscale convective organization on the properties of convection (e.g., mixing between updrafts and environment), parameterizing the degree of convective organization has only recently been attempted in cumulus parameterization schemes (e.g., Unified Convection Scheme UNICON). Additionally, challenges remain in determining the degree of convective organization from observations and in comparing directly with the organization metrics in model simulations. This study addresses the need to objectively quantify the degree of mesoscale convective organization using high quality S-PolKa radar data from the DYNAMO field campaign. One of the most noticeable aspects of mesoscale convective organization in radar data is the degree of convective clustering, which can be characterized by the number and size distribution of convective echoes and the distance between them. We propose a method of defining contiguous convective echoes (CCEs) using precipitating convective echoes identified by a rain type classification algorithm. Two classification algorithms, Steiner et al. (1995) and Powell et al. (2016), are tested and evaluated against high-resolution WRF simulations to determine which method better represents the degree of convective clustering. Our results suggest that the CCEs based on Powell et al.'s algorithm better represent the dynamical properties of the convective updrafts and thus provide the basis of a metric for convective organization. Furthermore, through a comparison with the observational data, the WRF simulations driven by the DYNAMO large-scale forcing, similarly applied to UNICON Single Column Model simulations, will allow us to evaluate the ability of both WRF and UNICON to simulate convective clustering. This evaluation is based on the physical processes that are explicitly represented in WRF and UNICON, including the mechanisms leading to convective clustering, and the feedback to the convective properties.

  1. Synthetic aperture radar capabilities in development

    Energy Technology Data Exchange (ETDEWEB)

    Miller, M. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    The Imaging and Detection Program (IDP) within the Laser Program is currently developing an X-band Synthetic Aperture Radar (SAR) to support the Joint US/UK Radar Ocean Imaging Program. The radar system will be mounted in the program`s Airborne Experimental Test-Bed (AETB), where the initial mission is to image ocean surfaces and better understand the physics of low grazing angle backscatter. The Synthetic Aperture Radar presentation will discuss its overall functionality and a brief discussion on the AETB`s capabilities. Vital subsystems including radar, computer, navigation, antenna stabilization, and SAR focusing algorithms will be examined in more detail.

  2. Radar application in void and bar detection

    International Nuclear Information System (INIS)

    Amry Amin Abas; Mohamad Pauzi Ismail; Suhairy Sani

    2003-01-01

    Radar is one of the new non-destructive testing techniques for concrete and structures inspection. Radar is a non-ionizing electromagnetic wave that can penetrate deep into concrete or soil in about several tenths of meters. Method of inspection using radar enables us to perform high resolution detection, imaging and mapping of subsurface concrete and soil condition. This paper will discuss the use of radar for void and bar detection and sizing. The samples used in this paper are custom made samples and comparison will be made to validate the use of radar in detecting, locating and also size determination of voids and bars. (Author)

  3. An assimilation test of Doppler radar reflectivity and radial velocity from different height layers in improving the WRF rainfall forecasts

    Science.gov (United States)

    Tian, Jiyang; Liu, Jia; Yan, Denghua; Li, Chuanzhe; Chu, Zhigang; Yu, Fuliang

    2017-12-01

    Hydrological forecasts require high-resolution and accurate rainfall information, which is one of the most difficult variables to be captured by the mesoscale Numerical Weather Prediction (NWP) systems. Radar data assimilation is an effective method for improving rainfall forecasts by correcting the initial and lateral boundary conditions of the NWP system. The aim of this study is to explore an efficient way of utilizing the Doppler radar observations for data assimilation, which is implemented by exploring the effect of assimilating radar data from different height layers on the improvement of the NWP rainfall accuracy. The Weather Research and Forecasting (WRF) model is used for numerical rainfall forecast in the Zijingguan catchment located in the ;Jing-Jin-Ji; (Beijing-Tianjin-Hebei) Region of Northern China, and the three-dimensional variational data assimilation (3-DVar) technique is adopted to assimilate the radar data. Radar reflectivity and radial velocity are assimilated separately and jointly. Each type of radar data is divided into seven data sets according to the height layers: (1) 2000 m, and (7) all layers. The results show that radar reflectivity assimilation leads to better results than radial velocity assimilation. The accuracy of the forecasted rainfall deteriorates with the rise of the height of the assimilated radar reflectivity. The same results can be found when assimilating radar reflectivity and radial velocity at the same time. The conclusions of this study provide a reference for efficient assimilation of the radar data in improving the NWP rainfall products.

  4. Radar meteor rates and solar activity

    International Nuclear Information System (INIS)

    Prikryl, P.

    1983-01-01

    The short-term variation of diurnal radar meteor rates with solar activity represented by solar microwave flux Fsub(10.7), and sunspots relative number Rsub(z), is investigated. Applying the superposed-epoch analysis to the observational material of radar meteor rates from Christchurch (1960-61 and 1963-65), a decrease in the recorded radar rates is found during days of enhanced solar activity. No effect of geomagnetic activity similar to the one reported for the Swedish and Canadian radar meteor data was found by the author in the Christchurch data. A possible explanation of the absence of the geomagnetic effect on radar meteor rates from New Zealand due to a lower echo ceiling height of the Christchurch radar is suggested. The variation of the atmospheric parameters as a possible cause of the observed variation in radar meteor rates is also discussed. (author)

  5. Reconfigurable L-band Radar Transceiver using Digital Signal Synthesis, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — This Phase II proposal, builds upon the extensive research and digital radar design that has been successfully completed during the Phase I contract. Key innovations...

  6. 3-D Imaging by Laser Radar and Applications in Preventing and Combating Crime and Terrorism

    National Research Council Canada - National Science Library

    Letalick, Dietmar; Ahlberg, Joergen; Andersson, Pierre; Chevalier, Tomas; Groenwall, Christina; Larsson, Hakan; Persson, Asa; Klasen, Lena

    2004-01-01

    This paper describes the ongoing research on 3-dimensional (3-D) imaging at FOI. Specifically, we address the new possibilities brought by laser radars, focusing on systems for high resolution 3-D imaging...

  7. Soft-core dataflow processor architecture optimised for radar signal processing: Article

    CSIR Research Space (South Africa)

    Broich, R

    2014-10-01

    Full Text Available Current radar signal processors lack either performance or flexibility. Custom soft-core processors exhibit potential in high-performance signal processing applications, yet remain relatively unexplored in research literature. In this paper, we use...

  8. Filtration of the FMICW radar output signals by the advanced windows

    African Journals Online (AJOL)

    Filtration of the FMICW radar output signals by the advanced windows. ... PROMOTING ACCESS TO AFRICAN RESEARCH ... This paper deals with the special types of windows application on the two dimensional spectrum obtained using the ...

  9. Comparative study of MLT mean winds using MF radars located at ...

    Indian Academy of Sciences (India)

    Medium Frequency Radar, Indian Institute of Geomagnetism, Shivaji University ... Research Laboratory, Indian Institute of Geomagnetism, Tirunelveli 627 011, India. ... paper is to describe mesosphere and lower thermosphere (MLT) wind field.

  10. Overview of Experimental Pulse-Doppler Radar Data Collected Oct 1999

    National Research Council Canada - National Science Library

    Hughes, Steven

    2000-01-01

    The Defence Research Establishment Ottawa has designed and constructed an experimental air-to-air radar system as the first step in demonstrating an air-to-air surveillance capability for the Canadian...

  11. Wind profile radar for study of Antarctic air circulation. Progetto di un radar 'wind-profiler' per lo studio della circolazione atmosferica antartica

    Energy Technology Data Exchange (ETDEWEB)

    Ragaini, E.; Sarango, M.F.; Vasquez, E.H.

    1992-10-01

    After a brief discussion of meteorological methods used in the Antarctic, the paper gives an outline of a coordinated international research project whose objective is to set up a wind profiler radar station that would give meteorologists information regarding Antarctic atmospheric dynamics useful in their investigation of the causes and effects of the hole in the ozone layer. The radar instrumentation is to provide continuous readings of wind velocity at varying altitudes above the polar continent.

  12. Weather Radar Estimations Feeding an Artificial Neural Network Model Weather Radar Estimations Feeding an Artificial Neural Network Model

    Directory of Open Access Journals (Sweden)

    Dawei Han

    2012-02-01

    Full Text Available The application of ANNs (Artifi cial Neural Networks has been studied by many researchers in modelling rainfall runoff processes. However, the work so far has been focused on the rainfall data from traditional raingauges. Weather radar is a modern technology which could provide high resolution rainfall in time and space. In this study, a comparison in rainfall runoff modelling between the raingauge and weather radar has been carried out. The data were collected from Brue catchment in Southwest of England, with 49 raingauges covering 136 km2 and two C-band weather radars. This raingauge network is extremely dense (for research purposes and does not represent the usual raingauge density in operational flood forecasting systems. The ANN models were set up with both lumped and spatial rainfall input. The results showed that raingauge data outperformed radar data in all the events tested, regardless of the lumped and spatial input. La aplicación de Redes Neuronales Artificiales (RNA en el modelado de lluvia-flujo ha sido estudiada ampliamente. Sin embargo, hasta ahora se han utilizado datos provenientes de pluviómetros tradicionales. Los radares meteorológicos son una tecnología moderna que puede proveer datos de lluvia de alta resolución en tiempo y espacio. Este es un trabajo de comparación en el modelado lluvia-flujo entre pluviómetros y radares meteorológicos. Los datos provienen de la cuenca del río Brue en el suroeste de Inglaterra, con 49 pluviómetros cubriendo 136 km2 y dos radares meteorológicos en la banda C. Esta red de pluviómetros es extremadamente densa (para investigación y no representa la densidad usual en sistemas de predicción de inundaciones. Los modelos de RNA fueron implementados con datos de entrada de lluvia tanto espaciados como no distribuidos. Los resultados muestran que los datos de los pluviómetros fueron mejores que los datos de los radares en todos los eventos probados.

  13. Study of the Bistatic Radar Cross Section of a 155-mm Artillery Round

    Science.gov (United States)

    2017-06-01

    ARL-TR-8045 ● JUNE 2017 US Army Research Laboratory Study of the Bistatic Radar Cross Section of a 155-mm Artillery Round by...when it is no longer needed. Do not return it to the originator. ARL-TR-8045 ● JUNE 2017 US Army Research Laboratory Study of the...signature. This means that as far as polarization goes, the bistatic radar is an example where the reciprocity principle cannot be applied . Finally, we

  14. Radar Rainfall Statistics During PECAN

    Science.gov (United States)

    Romatschke, U.; Weckwerth, T.

    2017-12-01

    The Plains Elevated Convection At Night (PECAN) field campaign, based in Kansas, USA, took place from May to July 2015. It was designed to understand the causes and improve predictions of the central US nocturnal precipitation maximum. Over 100 instruments were utilized to sample the pre-convective and convective conditions within and around unorganized storms and Mesoscale Convective Systems (MCSs). We analyze quantitative precipitation estimates (QPEs) derived from a dense network of NEXRADs which, combined with S-Pol, cover an area extending from the eastern side of the Rocky Mountains over the Central Great Plains. As expected, precipitation maxima occurred during the afternoon and evening over the eastern Rocky Mountains and during the night over the plains. The precipitation over the mountains is almost exclusively associated with smaller scale storms which are triggered by solar heating over the elevated terrain. The mountain triggered storms quickly grow and merge to the size of MCSs and are then advected east over the plains. Storms are also initiated over the plains but at much lower frequency than over the mountains. The diurnal cycle of plain initiation is much less pronounced with a broad peak in the afternoon and evening but also significant convection initiation during the night. The nocturnal precipitation over the plains is primarily associated with the MCSs advected from the mountains which merge with the storms triggered over the plains. Some precipitation over the plains is generated by pristine storms triggered over the plains but their precipitation contribution is mostly secondary compared to the merged systems.

  15. Radar observations of Comet Halley

    International Nuclear Information System (INIS)

    Campbell, D.B.; Harmon, J.K.; Shapiro, I.I.

    1989-01-01

    Five nights of Arecibo radar observations of Comet Halley are reported which reveal a feature in the overall average spectrum which, though weak, seems consistent with being an echo from the comet. The large radar cross section and large bandwidth of the feature suggest that the echo is predominantly from large grains which have been ejected from the nucleus. Extrapolation of the dust particle size distribution to large grain sizes gives a sufficient number of grains to account for the echo. The lack of a detectable echo from the nucleus, combined with estimates of its size and rotation rate from spacecraft encounters and other data, indicate that the nucleus has a surface of relatively high porosity. 33 references

  16. Terahertz radar cross section measurements.

    Science.gov (United States)

    Iwaszczuk, Krzysztof; Heiselberg, Henning; Jepsen, Peter Uhd

    2010-12-06

    We perform angle- and frequency-resolved radar cross section (RCS) measurements on objects at terahertz frequencies. Our RCS measurements are performed on a scale model aircraft of size 5-10 cm in polar and azimuthal configurations, and correspond closely to RCS measurements with conventional radar on full-size objects. The measurements are performed in a terahertz time-domain system with freely propagating terahertz pulses generated by tilted pulse front excitation of lithium niobate crystals and measured with sub-picosecond time resolution. The application of a time domain system provides ranging information and also allows for identification of scattering points such as weaponry attached to the aircraft. The shapes of the models and positions of reflecting parts are retrieved by the filtered back projection algorithm.

  17. Radar Control Optimal Resource Allocation

    Science.gov (United States)

    2015-07-13

    Dartmouth, Nova Scotia, Canada by the McMaster University Intelligent PIXel (IPIX) X-band Polarimetric Coherent Radar during the OHGR - Dartmouth...following coefficients [ q2, 4p22q, 12p12q, 12p11q, 12|P | ] (26) for A4 and [ q2, 4p22q, 4q(3 p12 + r22), 12(p11q + p22r22 − qr12), 12(|P |+ 2r22p12

  18. Radar channel balancing with commutation

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter

    2014-02-01

    When multiple channels are employed in a pulse-Doppler radar, achieving and maintaining balance between the channels is problematic. In some circumstances the channels may be commutated to achieve adequate balance. Commutation is the switching, trading, toggling, or multiplexing of the channels between signal paths. Commutation allows modulating the imbalance energy away from the balanced energy in Doppler, where it can be mitigated with filtering.

  19. Radar-based hail detection

    Czech Academy of Sciences Publication Activity Database

    Skripniková, Kateřina; Řezáčová, Daniela

    2014-01-01

    Roč. 144, č. 1 (2014), s. 175-185 ISSN 0169-8095 R&D Projects: GA ČR(CZ) GAP209/11/2045; GA MŠk LD11044 Institutional support: RVO:68378289 Keywords : hail detection * weather radar * hail damage risk Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 2.844, year: 2014 http://www.sciencedirect.com/science/article/pii/S0169809513001804

  20. Radar-eddy current GPR

    OpenAIRE

    A. O. Abramovych

    2014-01-01

    Introduction. At present there are many electrical schematic metal detectors (the most common kind of ground penetrating radar), which are differ in purpose. Each scheme has its own advantages and disadvantages compared to other schemes. Designing metal detector problem of optimal selection of functional units most schemes can only work with a narrow range of special purpose units. Functional units used in circuits can be replaced by better ones, but specialization schemes do not provide such...

  1. The Python ARM Radar Toolkit (Py-ART, a Library for Working with Weather Radar Data in the Python Programming Language

    Directory of Open Access Journals (Sweden)

    Jonathan J Helmus

    2016-07-01

    Full Text Available The Python ARM Radar Toolkit is a package for reading, visualizing, correcting and analysing data from weather radars. Development began to meet the needs of the Atmospheric Radiation Measurement Climate Research Facility and has since expanded to provide a general-purpose framework for working with data from weather radars in the Python programming language. The toolkit is built on top of libraries in the Scientific Python ecosystem including NumPy, SciPy, and matplotlib, and makes use of Cython for interfacing with existing radar libraries written in C and to speed up computationally demanding algorithms. The source code for the toolkit is available on GitHub and is distributed under a BSD license.

  2. Detecting and classifying low probability of intercept radar

    CERN Document Server

    Pace, Philip E

    2008-01-01

    This revised and expanded second edition brings you to the cutting edge with new chapters on LPI radar design, including over-the-horizon radar, random noise radar, and netted LPI radar. You also discover critical LPI detection techniques, parameter extraction signal processing techniques, and anti-radiation missile design strategies to counter LPI radar.

  3. Combining C- and X-band Weather Radars for Improving Precipitation Estimates over Urban Areas

    DEFF Research Database (Denmark)

    Nielsen, Jesper Ellerbæk

    of future system state. Accurate and reliable weather radar measurements are, therefore, important for future developments and achievements within urban drainage. This PhD study investigates two types of weather radars. Both systems are in operational use in Denmark today. A network of meteorological C...... individually and owned by local water utility companies. Although the two radar systems use similar working principles, the systems have significant differences regarding technology, temporal resolution, spatial resolution, range and scanning strategy. The focus of the research was to combine the precipitation...

  4. Improving Weather Radar Precipitation Estimates by Combining two Types of Radars

    DEFF Research Database (Denmark)

    Nielsen, Jesper Ellerbæk; Thorndahl, Søren Liedtke; Rasmussen, Michael R.

    2014-01-01

    This paper presents a demonstration of how Local Area Weather Radar (LAWR) X-band measurements can be combined with meteorological C–band measurements into a single radar product. For this purpose, a blending method has been developed which combines the strengths of the two radar systems. Combining...... the two radar types achieves a radar product with both long range and high temporal resolution. It is validated that the blended radar product performs better than the individual radars based on ground observations from laser disdrometers. However, the data combination is challenged by lower performance...... of the LAWR. Although both radars benefits from the data combination, it is also found that advection based temporal interpolation is a more favourable method for increasing the temporal resolution of meteorological C–band measurements....

  5. Radar probing of the auroral plasma

    International Nuclear Information System (INIS)

    Brekke, A.

    1977-01-01

    The European Incoherent Scatter Radar in the Auroral Zone (EISCAT) is an intereuropean organization planning to install an incoherent scatter radar system in Northern Scandinavia. It is supported by Finland, France, Norway, Great Britain, Sweden and West Germany, and its headquarters is in Kiruna, Sweden. The radar is planned to be operating in 1979. In order to introduce students and young scientists to the incoherent scatter radar technique, a summer school was held in Tromsoe, from 5th to 13th June 1975. In these proceedings an introduction to the basic theory of fluctuations in a plasma is given. Some of the present incoherent scatter radars now in use are presented and special considerations with respect to the planned EISACT facility are discussed. Reviews of some recent results and scientific problems relevant to EISCAT are also presented and finally a presentation of some observational techniques complementary to incoherent scatter radars is included. (Ed.)

  6. Utilizing Q-Learning to allow a radar to choose its transmit frequency, adapting to its environment

    CSIR Research Space (South Africa)

    Wabeke, LO

    2010-06-01

    Full Text Available Recent research show that utilization of knowledge of the environment can allow a radar system to adapt its processing to improve its performance. Furthermore, a radar system that utilize both a-priori and measured knowledge in an adaptive close...

  7. Tactile Radar: experimenting a computer game with visually disabled.

    Science.gov (United States)

    Kastrup, Virgínia; Cassinelli, Alvaro; Quérette, Paulo; Bergstrom, Niklas; Sampaio, Eliana

    2017-09-18

    Visually disabled people increasingly use computers in everyday life, thanks to novel assistive technologies better tailored to their cognitive functioning. Like sighted people, many are interested in computer games - videogames and audio-games. Tactile-games are beginning to emerge. The Tactile Radar is a device through which a visually disabled person is able to detect distal obstacles. In this study, it is connected to a computer running a tactile-game. The game consists in finding and collecting randomly arranged coins in a virtual room. The study was conducted with nine congenital blind people including both sexes, aged 20-64 years old. Complementary methods of first and third person were used: the debriefing interview and the quasi-experimental design. The results indicate that the Tactile Radar is suitable for the creation of computer games specifically tailored for visually disabled people. Furthermore, the device seems capable of eliciting a powerful immersive experience. Methodologically speaking, this research contributes to the consolidation and development of first and third person complementary methods, particularly useful in disabled people research field, including the evaluation by users of the Tactile Radar effectiveness in a virtual reality context. Implications for rehabilitation Despite the growing interest in virtual games for visually disabled people, they still find barriers to access such games. Through the development of assistive technologies such as the Tactile Radar, applied in virtual games, we can create new opportunities for leisure, socialization and education for visually disabled people. The results of our study indicate that the Tactile Radar is adapted to the creation of video games for visually disabled people, providing a playful interaction with the players.

  8. Lightning Initiation Forecasting: An Operational Dual-Polarimetric Radar Technique

    Science.gov (United States)

    Woodard, Crystal J.; Carey, L. D.; Petersen, W. A.; Roeder, W. P.

    2011-01-01

    The objective of this NASA MSFC and NOAA CSTAR funded study is to develop and test operational forecast algorithms for the prediction of lightning initiation utilizing the C-band dual-polarimetric radar, UAHuntsville's Advanced Radar for Meteorological and Operational Research (ARMOR). Although there is a rich research history of radar signatures associated with lightning initiation, few studies have utilized dual-polarimetric radar signatures (e.g., Z(sub dr) columns) and capabilities (e.g., fuzzy-logic particle identification [PID] of precipitation ice) in an operational algorithm for first flash forecasting. The specific goal of this study is to develop and test polarimetric techniques that enhance the performance of current operational radar reflectivity based first flash algorithms. Improving lightning watch and warning performance will positively impact personnel safety in both work and leisure environments. Advanced warnings can provide space shuttle launch managers time to respond appropriately to secure equipment and personnel, while they can also provide appropriate warnings for spectators and players of leisure sporting events to seek safe shelter. Through the analysis of eight case dates, consisting of 35 pulse-type thunderstorms and 20 non-thunderstorm case studies, lightning initiation forecast techniques were developed and tested. The hypothesis is that the additional dual-polarimetric information could potentially reduce false alarms while maintaining high probability of detection and increasing lead-time for the prediction of the first lightning flash relative to reflectivity-only based techniques. To test the hypothesis, various physically-based techniques using polarimetric variables and/or PID categories, which are strongly correlated to initial storm electrification (e.g., large precipitation ice production via drop freezing), were benchmarked against the operational reflectivity-only based approaches to find the best compromise between

  9. The Comet Radar Explorer Mission

    Science.gov (United States)

    Asphaug, Erik; Belton, Mike; Bockelee-Morvan, Dominique; Chesley, Steve; Delbo, Marco; Farnham, Tony; Gim, Yonggyu; Grimm, Robert; Herique, Alain; Kofman, Wlodek; Oberst, Juergen; Orosei, Roberto; Piqueux, Sylvain; Plaut, Jeff; Robinson, Mark; Sava, Paul; Heggy, Essam; Kurth, William; Scheeres, Dan; Denevi, Brett; Turtle, Elizabeth; Weissman, Paul

    2014-11-01

    Missions to cometary nuclei have revealed major geological surprises: (1) Global scale layers - do these persist through to the interior? Are they a record of primary accretion? (2) Smooth regions - are they landslides originating on the surface? Are they cryovolcanic? (3) Pits - are they impact craters or sublimation pits, or rooted in the interior? Unambiguous answers to these and other questions can be obtained by high definition 3D radar reflection imaging (RRI) of internal structure. RRI can answer many of the great unknowns in planetary science: How do primitive bodies accrete? Are cometary nuclei mostly ice? What drives their spectacular activity and evolution? The Comet Radar Explorer (CORE) mission will image the detailed internal structure of the nucleus of 10P/Tempel 2. This ~16 x 8 x 7 km Jupiter Family Comet (JFC), or its parent body, originated in the outer planets region possibly millions of years before planet formation. CORE arrives post-perihelion and observes the comet’s waning activity from safe distance. Once the nucleus is largely dormant, the spacecraft enters a ~20-km dedicated Radar Mapping Orbit (RMO). The exacting design of the RRI experiment and the precise navigation of RMO will achieve a highly focused 3D radar reflection image of internal structure, to tens of meters resolution, and tomographic images of velocity and attenuation to hundreds of meters resolution, tied to the gravity model and shape. Visible imagers will produce maps of the surface morphology, albedo, color, texture, and photometric response, and images for navigation and shape determination. The cameras will also monitor the structure and dynamics of the coma, and its dusty jets, allowing their correlation in 3D with deep interior structures and surface features. Repeated global high-resolution thermal images will probe the near-surface layers heated by the Sun. Derived maps of thermal inertia will be correlated with the radar boundary response, and photometry and

  10. Radar imaging of Saturn's rings

    Science.gov (United States)

    Nicholson, Philip D.; French, Richard G.; Campbell, Donald B.; Margot, Jean-Luc; Nolan, Michael C.; Black, Gregory J.; Salo, Heikki J.

    2005-09-01

    We present delay-Doppler images of Saturn's rings based on radar observations made at Arecibo Observatory between 1999 and 2003, at a wavelength of 12.6 cm and at ring opening angles of 20.1°⩽|B|⩽26.7°. The average radar cross-section of the A ring is ˜77% relative to that of the B ring, while a stringent upper limit of 3% is placed on the cross-section of the C ring and 9% on that of the Cassini Division. These results are consistent with those obtained by Ostro et al. [1982, Icarus 49, 367-381] from radar observations at |B|=21.4°, but provide higher resolution maps of the rings' reflectivity profile. The average cross-section of the A and B rings, normalized by their projected unblocked area, is found to have decreased from 1.25±0.31 to 0.74±0.19 as the rings have opened up, while the circular polarization ratio has increased from 0.64±0.06 to 0.77±0.06. The steep decrease in cross-section is at variance with previous radar measurements [Ostro et al., 1980, Icarus 41, 381-388], and neither this nor the polarization variations are easily understood within the framework of either classical, many-particle-thick or monolayer ring models. One possible explanation involves vertical size segregation in the rings, whereby observations at larger elevation angles which see deeper into the rings preferentially see the larger particles concentrated near the rings' mid-plane. These larger particles may be less reflective and/or rougher and thus more depolarizing than the smaller ones. Images from all four years show a strong m=2 azimuthal asymmetry in the reflectivity of the A ring, with an amplitude of ±20% and minima at longitudes of 67±4° and 247±4° from the sub-Earth point. We attribute the asymmetry to the presence of gravitational wakes in the A ring as invoked by Colombo et al. [1976, Nature 264, 344-345] to explain the similar asymmetry long seen at optical wavelengths. A simple radiative transfer model suggests that the enhancement of the azimuthal

  11. Short-term ensemble radar rainfall forecasts for hydrological applications

    Science.gov (United States)

    Codo de Oliveira, M.; Rico-Ramirez, M. A.

    2016-12-01

    Flooding is a very common natural disaster around the world, putting local population and economy at risk. Forecasting floods several hours ahead and issuing warnings are of main importance to permit proper response in emergency situations. However, it is important to know the uncertainties related to the rainfall forecasting in order to produce more reliable forecasts. Nowcasting models (short-term rainfall forecasts) are able to produce high spatial and temporal resolution predictions that are useful in hydrological applications. Nonetheless, they are subject to uncertainties mainly due to the nowcasting model used, errors in radar rainfall estimation, temporal development of the velocity field and to the fact that precipitation processes such as growth and decay are not taken into account. In this study an ensemble generation scheme using rain gauge data as a reference to estimate radars errors is used to produce forecasts with up to 3h lead-time. The ensembles try to assess in a realistic way the residual uncertainties that remain even after correction algorithms are applied in the radar data. The ensembles produced are compered to a stochastic ensemble generator. Furthermore, the rainfall forecast output was used as an input in a hydrodynamic sewer network model and also in hydrological model for catchments of different sizes in north England. A comparative analysis was carried of how was carried out to assess how the radar uncertainties propagate into these models. The first named author is grateful to CAPES - Ciencia sem Fronteiras for funding this PhD research.

  12. Probing Small Lakes on Titan Using the Cassini RADAR Altimeter

    Science.gov (United States)

    Mastrogiuseppe, M.; Poggiali, V.; Hayes, A.; Lunine, J. I.; Seu, R.; Lorenz, R. D.; Mitri, G.; Mitchell, K. L.; Janssen, M. A.; Casarano, D.; Notarnicola, C.; Le Gall, A. A.

    2017-12-01

    The T126 Cassini's final flyby of Titan has offered a unique opportunity to observe an area in the Northern Polar terrain, where several small - medium size (10 - 50 km) hydrocarbon lakes are present and have been previously imaged by Cassini. The successful observation allowed the radar to operate at the closest approach over several small lakes, using its altimetry mode for the investigation of depth and liquid composition. Herein we present the result of a dedicate processing previously applied to altimetric data acquired over Ligeia Mare where the radar revealed the bathymetry and composition of the sea [1,2]. We show that, the optimal geometry condition met during the T126 fly-by allowed the radar to probe Titan's lakes revealing that such small liquid bodies can exceed one-hundred meters of depth. [1] M. Mastrogiuseppe et al. (2014, Mar.). The bathymetry of a Titan Sea. Geophysical Research Letters. [Online]. 41 (5), pp. 1432-1437. Available: http://dx.doi.org/10.1002/2013GL058618 [2] M.Mastrogiuseppe et al. (2016, Oct). Radar Sounding Using the Cassini Altimeter: Waveform Modeling and Monte Carlo Approach for Data Inversion of Observations of Titan's Seas, IEEE Transactions On Geoscience And Remote Sensing, Vol. 54, No. 10, doi: 10.1109/TGRS.2016.2563426.

  13. Textural features for radar image analysis

    Science.gov (United States)

    Shanmugan, K. S.; Narayanan, V.; Frost, V. S.; Stiles, J. A.; Holtzman, J. C.

    1981-01-01

    Texture is seen as an important spatial feature useful for identifying objects or regions of interest in an image. While textural features have been widely used in analyzing a variety of photographic images, they have not been used in processing radar images. A procedure for extracting a set of textural features for characterizing small areas in radar images is presented, and it is shown that these features can be used in classifying segments of radar images corresponding to different geological formations.

  14. Signal compression in radar using FPGA

    OpenAIRE

    Escamilla Hemández, Enrique; Kravchenko, Víctor; Ponomaryov, Volodymyr; Duchen Sánchez, Gonzalo; Hernández Sánchez, David

    2010-01-01

    We present the hardware implementation of radar real time processing procedures using a simple, fast technique based on FPGA (Field Programmable Gate Array) architecture. This processing includes different window procedures during pulse compression in synthetic aperture radar (SAR). The radar signal compression processing is realized using matched filter, and classical and novel window functions, where we focus on better solution for minimum values of sidelobes. The proposed architecture expl...

  15. Tangent hyperbolic circular frequency diverse array radars

    Directory of Open Access Journals (Sweden)

    Sarah Saeed

    2016-03-01

    Full Text Available Frequency diverse array (FDA with uniform frequency offset (UFO has been in spot light of research for past few years. Not much attention has been devoted to non-UFOs in FDA. This study investigates tangent hyperbolic (TH function for frequency offset selection scheme in circular FDAs (CFDAs. Investigation reveals a three-dimensional single-maximum beampattern, which promises to enhance system detection capability and signal-to-interference plus noise ratio. Furthermore, by utilising the versatility of TH function, a highly configurable type array system is achieved, where beampatterns of three different configurations of FDA can be generated, just by adjusting a single function parameter. This study further examines the utility of the proposed TH-CFDA in some practical radar scenarios.

  16. Sixteenth International Laser Radar Conference, Part 1

    International Nuclear Information System (INIS)

    Mccormick, M.P.

    1992-07-01

    This publication contains extended abstracts of papers presented at the 16th International Laser Radar Conference. One-hundred ninety-five papers were presented in both oral and poster sessions. The topics of the conference sessions were: (1) Mt. Pinatubo Volcanic Dust Layer Observations; (2) Global Change/Ozone Measurements; (3) GLOBE/LAWS/LITE; (4) Mesospheric Measurements and Measurement Systems; (5) Middle Atmosphere; (6) Wind Measurements and Measurement Systems; (7) Imaging and Ranging; (8) Water Vapor Measurements; (9) Systems and Facilities; and (10) Laser Devices and Technology. This conference reflects the breadth of research activities being conducted in the lidar field. These abstracts address subjects from lidar-based atmospheric investigations relating to global change to the development of new lidar systems and technology

  17. Radar reflection off extensive air showers

    Directory of Open Access Journals (Sweden)

    Werner F.

    2013-06-01

    Full Text Available We investigate the possibility of detecting extensive air showers by the radar technique. Considering a bistatic radar system and different shower geometries, we simulate reflection of radio waves off the static plasma produced by the shower in the air. Using the Thomson cross-section for radio wave reflection, we obtain the time evolution of the signal received by the antennas. The frequency upshift of the radar echo and the power received are studied to verify the feasibility of the radar detection technique.

  18. Preliminary Analysis of X-Band and Ka-Band Radar for Use in the Detection of Icing Conditions Aloft

    Science.gov (United States)

    Reehorst, Andrew L.; Koenig, George G.

    2004-01-01

    NASA and the U.S. Army Cold Regions Research and Engineering Laboratory (CRREL) have an on-going activity to develop remote sensing technologies for the detection and measurement of icing conditions aloft. Radar has been identified as a strong tool for this work. However, since the remote detection of icing conditions with the intent to identify areas of icing hazard is a new and evolving capability, there are no set requirements for radar sensitivity. This work is an initial attempt to quantify, through analysis, the sensitivity requirements for an icing remote sensing radar. The primary radar of interest for cloud measurements is Ka-band, however, since NASA is currently using an X-band unit, this frequency is also examined. Several aspects of radar signal analysis were examined. Cloud reflectivity was calculated for several forms of cloud using two different techniques. The Air Force Geophysical Laboratory (AFGL) cloud models, with different drop spectra represented by a modified gamma distribution, were utilized to examine several categories of cloud formation. Also a fundamental methods approach was used to allow manipulation of the cloud droplet size spectra. And an analytical icing radar simulator was developed to examine the complete radar system response to a configurable multi-layer cloud environment. Also discussed is the NASA vertical pointing X-band radar. The radar and its data system are described, and several summer weather events are reviewed.

  19. The Next Generation of Airborne Polarimetric Doppler Weather Radar: NCAR/EOL Airborne Phased Array Radar (APAR) Development

    Science.gov (United States)

    Moore, James; Lee, Wen-Chau; Loew, Eric; Vivekanandan, Jothiram; Grubišić, Vanda; Tsai, Peisang; Dixon, Mike; Emmett, Jonathan; Lord, Mark; Lussier, Louis; Hwang, Kyuil; Ranson, James

    2017-04-01

    The National Center for Atmospheric Research (NCAR) Earth observing Laboratory (EOL) is entering the third year of preliminary system design studies, engineering prototype testing and project management plan preparation for the development of a novel Airborne Phased Array Radar (APAR). This system being designed by NCAR/EOL will be installed and operated on the NSF/NCAR C-130 aircraft. The APAR system will consist of four removable C-band Active Electronically Scanned Arrays (AESA) strategically placed on the fuselage of the aircraft. Each AESA measures approximately 1.5 x 1.9 m and is composed of 3000 active radiating elements arranged in an array of line replaceable units (LRU) to simplify maintenance. APAR will provide unprecedented observations, and in conjunction with the advanced radar data assimilation schema, will be able to address the key science questions to improve understanding and predictability of significant and high-impact weather APAR, operating at C-band, allows the measurement of 3-D kinematics of the more intense portions of storms (e.g. thunderstorm dynamics and tornadic development, tropical cyclone rainband structure and evolution) with less attenuation compared with current airborne Doppler radar systems. Polarimetric measurements are not available from current airborne tail Doppler radars. However, APAR, with dual-Doppler and dual polarization diversity at a lesser attenuating C-band wavelength, will further advance the understanding of the microphysical processes within a variety of precipitation systems. The radar is sensitive enough to provide high resolution measurements of winter storm dynamics and microphysics. The planned APAR development that would bring the system to operational readiness for research community use aboard the C-130 is expected to take 8 years once major funding support is realized. The authors will review the overall APAR design and provide new details of the system based on our Technical Requirements Document

  20. Nearshore Processes, Currents and Directional Wave Spectra Monitoring Using Coherent and Non-coherent Imaging Radars

    Science.gov (United States)

    Trizna, D.; Hathaway, K.

    2007-05-01

    Two new radar systems have been developed for real-time measurement of near-shore processes, and results are presented for measurements of ocean wave spectra, near-shore sand bar structure, and ocean currents. The first is a non-coherent radar based on a modified version of the Sitex radar family, with a data acquisition system designed around an ISR digital receiver card. The card operates in a PC computer with inputs from a Sitex radar modified for extraction of analogue signals for digitization. Using a 9' antenna and 25 kW transmit power system, data were collected during 2007 at the U.S. Army Corps of Engineers Field Research Facility (FRF), Duck, NC during winter and spring of 2007. The directional wave spectrum measurements made are based on using a sequence of 64 to 640 antenna rotations to form a snapshot series of radar images of propagating waves. A square window is extracted from each image, typically 64 x 64 pixels at 3-m resolution. Then ten sets of 64 windows are submitted to a three-dimensional Fast Fourier Transform process to generate radar image spectra in the frequency-wavenumber space. The relation between the radar image spectral intensity and wave spectral intensity derived from the FRF pressure gauge array was used for a test set of data, in order to establish a modulation transfer function (MTF) for each frequency component. For 640 rotations, 10 of such spectra are averaged for improved statistics. The wave spectrum so generated was compared for extended data sets beyond those used to establish the MTF, and those results are presented here. Some differences between the radar and pressure sensor data that are observed are found to be due to the influence of the wind field, as the radar echo image weakens for light winds. A model is developed to account for such an effect to improve the radar estimate of the directional wave spectrum. The radar ocean wave imagery is severely influenced only by extremely heavy rain-fall rates, so that

  1. Improved Micro Rain Radar snow measurements using Doppler spectra post-processing

    Directory of Open Access Journals (Sweden)

    M. Maahn

    2012-11-01

    Full Text Available The Micro Rain Radar 2 (MRR is a compact Frequency Modulated Continuous Wave (FMCW system that operates at 24 GHz. The MRR is a low-cost, portable radar system that requires minimum supervision in the field. As such, the MRR is a frequently used radar system for conducting precipitation research. Current MRR drawbacks are the lack of a sophisticated post-processing algorithm to improve its sensitivity (currently at +3 dBz, spurious artefacts concerning radar receiver noise and the lack of high quality Doppler radar moments. Here we propose an improved processing method which is especially suited for snow observations and provides reliable values of effective reflectivity, Doppler velocity and spectral width. The proposed method is freely available on the web and features a noise removal based on recognition of the most significant peak. A dynamic dealiasing routine allows observations even if the Nyquist velocity range is exceeded. Collocated observations over 115 days of a MRR and a pulsed 35.2 GHz MIRA35 cloud radar show a very high agreement for the proposed method for snow, if reflectivities are larger than −5 dBz. The overall sensitivity is increased to −14 and −8 dBz, depending on range. The proposed method exploits the full potential of MRR's hardware and substantially enhances the use of Micro Rain Radar for studies of solid precipitation.

  2. Radar network communication through sensing of frequency hopping

    Science.gov (United States)

    Dowla, Farid; Nekoogar, Faranak

    2013-05-28

    In one embodiment, a radar communication system includes a plurality of radars having a communication range and being capable of operating at a sensing frequency and a reporting frequency, wherein the reporting frequency is different than the sensing frequency, each radar is adapted for operating at the sensing frequency until an event is detected, each radar in the plurality of radars has an identification/location frequency for reporting information different from the sensing frequency, a first radar of the radars which senses the event sends a reporting frequency corresponding to its identification/location frequency when the event is detected, and all other radars in the plurality of radars switch their reporting frequencies to match the reporting frequency of the first radar upon detecting the reporting frequency switch of a radar within the communication range. In another embodiment, a method is presented for communicating information in a radar system.

  3. The NASA radar entomology program at Wallops Flight Center

    Science.gov (United States)

    Vaughn, C. R.

    1979-01-01

    NASA contribution to radar entomology is presented. Wallops Flight Center is described in terms of its radar systems. Radar tracking of birds and insects was recorded from helicopters for airspeed and vertical speed.

  4. Multiple-scattering in radar systems: A review

    International Nuclear Information System (INIS)

    Battaglia, Alessandro; Tanelli, Simone; Kobayashi, Satoru; Zrnic, Dusan; Hogan, Robin J.; Simmer, Clemens

    2010-01-01

    Although extensively studied within the lidar community, the multiple scattering phenomenon has always been considered a rare curiosity by radar meteorologists. Up to few years ago its appearance has only been associated with two- or three-body-scattering features (e.g. hail flares and mirror images) involving highly reflective surfaces. Recent atmospheric research aimed at better understanding of the water cycle and the role played by clouds and precipitation in affecting the Earth's climate has driven the deployment of high frequency radars in space. Examples are the TRMM 13.5 GHz, the CloudSat 94 GHz, the upcoming EarthCARE 94 GHz, and the GPM dual 13-35 GHz radars. These systems are able to detect the vertical distribution of hydrometeors and thus provide crucial feedbacks for radiation and climate studies. The shift towards higher frequencies increases the sensitivity to hydrometeors, improves the spatial resolution and reduces the size and weight of the radar systems. On the other hand, higher frequency radars are affected by stronger extinction, especially in the presence of large precipitating particles (e.g. raindrops or hail particles), which may eventually drive the signal below the minimum detection threshold. In such circumstances the interpretation of the radar equation via the single scattering approximation may be problematic. Errors will be large when the radiation emitted from the radar after interacting more than once with the medium still contributes substantially to the received power. This is the case if the transport mean-free-path becomes comparable with the instrument footprint (determined by the antenna beam-width and the platform altitude). This situation resembles to what has already been experienced in lidar observations, but with a predominance of wide- versus small-angle scattering events. At millimeter wavelengths, hydrometeors diffuse radiation rather isotropically compared to the visible or near infrared region where scattering is

  5. Method for radar detection of persons wearing wires

    OpenAIRE

    Fox, William P.

    2014-01-01

    8,730,098 B1 Methods are described for radar detection of persons wearing wires using radar spectra data including the vertical polarization (VV) radar cross section and the horizontal polarization (HH) radar cross section for a person. In one embodiment, the ratio of the vertical polarization (VV) radar cross section to the horizontal polarization (HH) radar cross section for a person is compared to a detection threshold to determine whether the person is wearing wire...

  6. Joint Efforts Towards European HF Radar Integration

    Science.gov (United States)

    Rubio, A.; Mader, J.; Griffa, A.; Mantovani, C.; Corgnati, L.; Novellino, A.; Schulz-Stellenfleth, J.; Quentin, C.; Wyatt, L.; Ruiz, M. I.; Lorente, P.; Hartnett, M.; Gorringe, P.

    2016-12-01

    During the past two years, significant steps have been made in Europe for achieving the needed accessibility to High Frequency Radar (HFR) data for a pan-European use. Since 2015, EuroGOOS Ocean Observing Task Teams (TT), such as HFR TT, are operational networks of observing platforms. The main goal is on the harmonization of systems requirements, systems design, data quality, improvement and proof of the readiness and standardization of HFR data access and tools. Particular attention is being paid by HFR TT to converge from different projects and programs toward those common objectives. First, JERICO-NEXT (Joint European Research Infrastructure network for Coastal Observatory - Novel European eXpertise for coastal observaTories, H2020 2015 Programme) will contribute on describing the status of the European network, on seeking harmonization through exchange of best practices and standardization, on developing and giving access to quality control procedures and new products, and finally on demonstrating the use of such technology in the general scientific strategy focused by the Coastal Observatory. Then, EMODnet (European Marine Observation and Data Network) Physics started to assemble HF radar metadata and data products within Europe in a uniform way. This long term program is providing a combined array of services and functionalities to users for obtaining free of charge data, meta-data and data products on the physical conditions of European sea basins and oceans. Additionally, the Copernicus Marine Environment Monitoring Service (CMEMS) delivers from 2015 a core information service to any user related to 4 areas of benefits: Maritime Safety, Coastal and Marine Environment, Marine Resources, and Weather, Seasonal Forecasting and Climate activities. INCREASE (Innovation and Networking for the integration of Coastal Radars into EuropeAn marine SErvices - CMEMS Service Evolution 2016) will set the necessary developments towards the integration of existing European

  7. INTERFEROMETRIC SYNTHETIC APERTURE RADAR (INSAR TECHNOLOGY AND GEOMORPHOLOGY INTERPRETATION

    Directory of Open Access Journals (Sweden)

    M. Maghsoudi

    2013-09-01

    Full Text Available Geomorphology is briefly the study of landforms and their formative processes on the surface of the planet earth as human habitat. The landforms evolution and the formative processes can best be studied by technologies with main application in study of elevation. Interferometric Synthetic Aperture Radar (InSAR is the appropriate technology for this application. With phase differences calculations in radar waves, the results of this technology can extensively be interpreted for geomorphologic researches. The purpose of the study is to review the geomorphologic studies using InSAR and also the technical studies about InSAR with geomorphologic interpretations. This study states that the InSAR technology can be recommended to be employed as a fundamental for geomorphology researches.

  8. Array-Based Ultrawideband through-Wall Radar: Prediction and Assessment of Real Radar Abilities

    Directory of Open Access Journals (Sweden)

    Nadia Maaref

    2013-01-01

    Full Text Available This paper deals with a new through-the-wall (TTW radar demonstrator for the detection and the localisation of people in a room (in a noncooperative way with the radar situated outside but in the vicinity of the first wall. After modelling the propagation through various walls and quantifying the backscattering by the human body, an analysis of the technical considerations which aims at defining the radar design is presented. Finally, an ultrawideband (UWB frequency modulated continuous wave (FMCW radar is proposed, designed, and implemented. Some representative trials show that this radar is able to localise and track moving people behind a wall in real time.

  9. Pocket radar guide key facts, equations, and data

    CERN Document Server

    Curry, G Richard

    2010-01-01

    ThePocket Radar Guideis a concise collection of key radar facts and important radar data that provides you with necessary radar information when you are away from your office or references. It includes statements and comments on radar design, operation, and performance; equations describing the characteristics and performance of radar systems and their components; and tables with data on radar characteristics and key performance issues.It is intended to supplement other radar information sources by providing a pocket companion to refresh memory and provide details whenever you need them such a

  10. Customizable Digital Receivers for Radar

    Science.gov (United States)

    Moller, Delwyn; Heavey, Brandon; Sadowy, Gregory

    2008-01-01

    Compact, highly customizable digital receivers are being developed for the system described in 'Radar Interferometer for Topographic Mapping of Glaciers and Ice Sheets' (NPO-43962), NASA Tech Briefs, Vol. 31, No. 7 (August 2007), page 72. The receivers are required to operate in unison, sampling radar returns received by the antenna elements in a digital beam-forming (DBF) mode. The design of these receivers could also be adapted to commercial radar systems. At the time of reporting the information for this article, there were no commercially available digital receivers capable of satisfying all of the operational requirements and compact enough to be mounted directly on the antenna elements. A provided figure depicts the overall system of which the digital receivers are parts. Each digital receiver includes an analog-to-digital converter (ADC), a demultiplexer (DMUX), and a field-programmable gate array (FPGA). The ADC effects 10-bit band-pass sampling of input signals having frequencies up to 3.5 GHz. The input samples are demultiplexed at a user-selectable rate of 1:2 or 1:4, then buffered in part of the FPGA that functions as a first-in/first-out (FIFO) memory. Another part of the FPGA serves as a controller for the ADC, DMUX, and FIFO memory and as an interface between (1) the rest of the receiver and (2) a front-panel data port (FPDP) bus, which is an industry-standard parallel data bus that has a high data-rate capability and multichannel configuration suitable for DBF. Still other parts of the FPGA in each receiver perform signal-processing functions. The digital receivers can be configured to operate in a stand-alone mode, or in a multichannel mode as needed for DBF. The customizability of the receiver makes it applicable to a broad range of system architectures. The capability for operation of receivers in either a stand-alone or a DBF mode enables the use of the receivers in an unprecedentedly wide variety of radar systems.

  11. Visual Attention to Radar Displays

    Science.gov (United States)

    Moray, N.; Richards, M.; Brophy, C.

    1984-01-01

    A model is described which predicts the allocation of attention to the features of a radar display. It uses the growth of uncertainty and the probability of near collision to call the eye to a feature of the display. The main source of uncertainty is forgetting following a fixation, which is modelled as a two dimensional diffusion process. The model was used to predict information overload in intercept controllers, and preliminary validation obtained by recording eye movements of intercept controllers in simulated and live (practice) interception.

  12. Radar Methods in Urban Environments

    Science.gov (United States)

    2016-10-26

    and A. Nehorai, "A low-complexity multi-target tracking algorithm in urban environments using sparse modeling ,’’ Signal Processing, Vol. 92, pp. 2199...AFRL-AFOSR-VA-TR-2016-0344 Radar Methods in Urban Environments Arye Nehorai WASHINGTON UNIVERSITY THE Final Report 10/26/2016 DISTRIBUTION A...of information   if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ORGANIZATION . 1. REPORT DATE

  13. Nowcasting of 1-h precipitation using radar and NWP data

    Czech Academy of Sciences Publication Activity Database

    Sokol, Zbyněk

    2006-01-01

    Roč. 328, 1-2 (2006), s. 200-211 ISSN 0022-1694 R&D Projects: GA ČR GA205/04/0114; GA AV ČR IBS3042101 Institutional research plan: CEZ:AV0Z30420517 Keywords : Precipitation forecast * Regression models * Nowcasting * Radar Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 2.117, year: 2006

  14. Inverse synthetic aperture radar imaging principles, algorithms and applications

    CERN Document Server

    Chen , Victor C

    2014-01-01

    Inverse Synthetic Aperture Radar Imaging: Principles, Algorithms and Applications is based on the latest research on ISAR imaging of moving targets and non-cooperative target recognition (NCTR). With a focus on the advances and applications, this book will provide readers with a working knowledge on various algorithms of ISAR imaging of targets and implementation with MATLAB. These MATLAB algorithms will prove useful in order to visualize and manipulate some simulated ISAR images.

  15. Doppler Processing with Ultra-Wideband (UWB) Radar Revisited

    Science.gov (United States)

    2018-01-01

    REPORT TYPE Technical Note 3. DATES COVERED (From - To) December 2017 4. TITLE AND SUBTITLE Doppler Processing with Ultra-Wideband (UWB) Radar...unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT This technical note revisits previous work performed at the US Army Research Laboratory related to...target considered previously is proportional to a delayed version of the transmitted signal, up to a complex constant factor. We write the received

  16. Ultra-wideband radar sensors and networks

    Science.gov (United States)

    Leach, Jr., Richard R; Nekoogar, Faranak; Haugen, Peter C

    2013-08-06

    Ultra wideband radar motion sensors strategically placed in an area of interest communicate with a wireless ad hoc network to provide remote area surveillance. Swept range impulse radar and a heart and respiration monitor combined with the motion sensor further improves discrimination.

  17. Weather radar rainfall data in urban hydrology

    NARCIS (Netherlands)

    Thorndahl, Søren; Einfalt, Thomas; Willems, Patrick; Ellerbæk Nielsen, Jesper; ten Veldhuis, J.A.E.; Arnbjerg-Nielsen, Karsten; Rasmussen, Michael R.; Molnar, Peter

    2017-01-01

    Application of weather radar data in urban hydrological applications has evolved significantly during the past decade as an alternative to traditional rainfall observations with rain gauges. Advances in radar hardware, data processing, numerical models, and emerging fields within urban hydrology

  18. High-precision positioning of radar scatterers

    NARCIS (Netherlands)

    Dheenathayalan, P.; Small, D.; Schubert, A.; Hanssen, R.F.

    2016-01-01

    Remote sensing radar satellites cover wide areas and provide spatially dense measurements, with millions of scatterers. Knowledge of the precise position of each radar scatterer is essential to identify the corresponding object and interpret the estimated deformation. The absolute position accuracy

  19. A Scanning Microwave Radar and Radiometer

    DEFF Research Database (Denmark)

    Skou, Niels

    1995-01-01

    The Scanning Microwave Radar and Radiometer (SMRR) is a line scanner featuring a combined radar and radiometer system operating around 35 and 94 GHz. The layout of the SMRR is shown. The 2 offset antenna parabolas scan in synchronism, the receiver antenna has the highest gain in order to ensure...

  20. Incidence angle normalization of radar backscatter data

    Science.gov (United States)

    NASA’s Soil Moisture Passive Active (SMAP) satellite (~2014) will include a radar system that will provide L-band multi-polarization backscatter at a constant incidence angle of 40º. During the pre-launch phase of the project there is a need for observations that will support the radar-based soil mo...

  1. Synthetic aperture radar: principles and applications

    International Nuclear Information System (INIS)

    Khan, N.A.; Yahya, K.M.

    2003-01-01

    In this paper an introduction to synthetic aperture radar is presented. Synthetic aperture radar is a relatively new remote sensing platform and the technology has matured a lot in the last two decades. This paper introduces the concepts behind SAR principles as well as the major areas where this new technology has shown additional information. (author)

  2. Wind energy applications of synthetic aperture radar

    DEFF Research Database (Denmark)

    Badger, Merete

    Synthetic aperture radars (SAR), mounted on satellites or aircraft, have proven useful for ocean wind mapping. Wind speeds at the height 10 m may be retrieved from measurements of radar backscatter using empirical model functions. The resulting windfields are valuable in offshore wind energy plan...

  3. Classification of Agricultural Crops in Radar Images

    NARCIS (Netherlands)

    Hoogeboom, P.

    1983-01-01

    For the past few years an accurate X-band SLAR system with digital recording has been available in The Netherlands. The images of this system are corrected to indicate radar backscatter coefficients (gamma) instead of arbitrary greytones. In 1980 a radar measurement campaign was organized in the

  4. Classification of radar echoes using fractal geometry

    International Nuclear Information System (INIS)

    Azzaz, Nafissa; Haddad, Boualem

    2017-01-01

    Highlights: • Implementation of two concepts of fractal geometry to classify two types of meteorological radar echoes. • A new approach, called a multi-scale fractal dimension is used for classification between fixed echoes and rain echoes. • An Automatic identification system of meteorological radar echoes was proposed using fractal geometry. - Abstract: This paper deals with the discrimination between the precipitation echoes and the ground echoes in meteorological radar images using fractal geometry. This study aims to improve the measurement of precipitations by weather radars. For this, we considered three radar sites: Bordeaux (France), Dakar (Senegal) and Me lbourne (USA). We showed that the fractal dimension based on contourlet and the fractal lacunarity are pertinent to discriminate between ground and precipitation echoes. We also demonstrated that the ground echoes have a multifractal structure but the precipitations are more homogeneous than ground echoes whatever the prevailing climate. Thereby, we developed an automatic classification system of radar using a graphic interface. This interface, based on the fractal geometry makes possible the identification of radar echoes type in real time. This system can be inserted in weather radar for the improvement of precipitation estimations.

  5. A Wing Pod-based Millimeter Wave Cloud Radar on HIAPER

    Science.gov (United States)

    Vivekanandan, Jothiram; Tsai, Peisang; Ellis, Scott; Loew, Eric; Lee, Wen-Chau; Emmett, Joanthan

    2014-05-01

    , occupy minimum cabin space and maximize scan coverage, a pod-based configuration was adopted. Currently, the radar system is capable of collecting observations between zenith and nadir in a fixed scanning mode. Measurements are corrected for aircraft attitude changes. The near-nadir and zenith pointing observations minimize the cross-track Doppler contamination in the radial velocity measurements. An extensive engineering monitoring mechanism is built into the recording system status such as temperature, pressure, various electronic components' status and receiver characteristics. Status parameters are used for real-time system stability estimates and correcting radar system parameters. The pod based radar system is mounted on a modified Gulfstream V aircraft, which is operated and maintained by the National Center for Atmospheric Research (NCAR) on behalf of the National Science Foundation (NSF). The aircraft is called the High-Performance Instrumented Airborne Platform for Environmental Research (HIAPER) (Laursen et al., 2006). It is also instrumented with high spectral resolution lidar (HSRL) and an array of in situ and remote sensors for atmospheric research. As part of the instrument suite for HIAPER, the NSF funded the development of the HIAPER Cloud Radar (HCR). The HCR is an airborne, millimeter-wavelength, dual-polarization, Doppler radar that serves the atmospheric science community by providing cloud remote sensing capabilities for the NSF/NCAR G-V (HIAPER) aircraft. An optimal radar configuration that is capable of maximizing the accuracy of both qualitative and quantitative estimated cloud microphysical and dynamical properties is the most attractive option to the research community. The Technical specifications of cloud radar are optimized for realizing the desired scientific performance for the pod-based configuration. The radar was both ground and flight tested and preliminary measurements of Doppler and polarization measurements were collected. HCR

  6. Millimeter wave radars raise weapon IQ

    Science.gov (United States)

    Lerner, E. J.

    1985-02-01

    The problems encountered by laser and IR homing devices for guided munitions may be tractable with warhead-mounted mm-wave radars. Operating at about 100 GHz and having several kilometers range, mm-wave radars see through darkness, fog, rain and smoke. The radar must be coupled with an analyzer that discerns moving and stationary targets and higher priority targets. The target lock-on can include shut-off of the transmitter and reception of naturally-generated mm-waves bouncing off the target when in the terminal phase of the flight. Monopulse transmitters have simplified the radar design, although mass production of finline small radar units has yet to be accomplished, particularly in combining GaAs, ferrites and other materials on one monolithic chip.

  7. Remote sensing with laser spectrum radar

    Science.gov (United States)

    Wang, Tianhe; Zhou, Tao; Jia, Xiaodong

    2016-10-01

    The unmanned airborne (UAV) laser spectrum radar has played a leading role in remote sensing because the transmitter and the receiver are together at laser spectrum radar. The advantages of the integrated transceiver laser spectrum radar is that it can be used in the oil and gas pipeline leak detection patrol line which needs the non-contact reflective detection. The UAV laser spectrum radar can patrol the line and specially detect the swept the area are now in no man's land because most of the oil and gas pipelines are in no man's land. It can save labor costs compared to the manned aircraft and ensure the safety of the pilots. The UAV laser spectrum radar can be also applied in the post disaster relief which detects the gas composition before the firefighters entering the scene of the rescue.

  8. Meteor observation by the Kyoto meteor radar

    International Nuclear Information System (INIS)

    Kato, S.; Tsuda, T.

    1987-01-01

    The Kyoto Meteor Radar is a monostatic coherent pulsed Doppler radar operating on the frequency of 31.57 MH. The system is computer controlled and uses radio interferometry for echo height determination. The antenna, an improvement, can be directed either to the north or the east. The system has been continuously collecting data on winds at meteor heights by radar observation. The meteor echo rate was also measured, the echo rate distribution with height and the daily variation in height integrated echo rate are discussed. Investigations of atmospheric tides are being pursued by cooperative observations. A novel approach to the study of gravity waves was attempted using the meteor radar which is able to detect the horizontal propagation of the waves by observing the changing phase through the region illuminated by the radar

  9. Progress in coherent laser radar

    Science.gov (United States)

    Vaughan, J. M.

    1986-01-01

    Considerable progress with coherent laser radar has been made over the last few years, most notably perhaps in the available range of high performance devices and components and the confidence with which systems may now be taken into the field for prolonged periods of operation. Some of this increasing maturity was evident at the 3rd Topical Meeting on Coherent Laser Radar: Technology and Applications. Topics included in discussions were: mesoscale wind fields, nocturnal valley drainage and clear air down bursts; airborne Doppler lidar studies and comparison of ground and airborne wind measurement; wind measurement over the sea for comparison with satellite borne microwave sensors; transport of wake vortices at airfield; coherent DIAL methods; a newly assembled Nd-YAG coherent lidar system; backscatter profiles in the atmosphere and wavelength dependence over the 9 to 11 micrometer region; beam propagation; rock and soil classification with an airborne 4-laser system; technology of a global wind profiling system; target calibration; ranging and imaging with coherent pulsed and CW system; signal fluctuations and speckle. Some of these activities are briefly reviewed.

  10. BALTRAD Advanced Weather Radar Networking

    Directory of Open Access Journals (Sweden)

    Daniel Michelson

    2018-03-01

    Full Text Available BALTRAD software exchanges weather-radar data internationally, operationally, and in real-time, and it processes the data using a common toolbox of algorithms available to every node in the decentralized radar network. This approach enables each node to access and process its own and international data to meet its local needs. The software system is developed collaboratively by the BALTRAD partnership, mostly comprising the national Meteorological and Hydrological institutes in the European Union’s Baltic Sea Region. The most important sub-systems are for data exchange, data management, scheduling and event handling, and data processing. C, Java, and Python languages are used depending on the sub-system, and sub-systems communicate using well-defined interfaces. Software is available from a dedicated Git server. BALTRAD software has been deployed throughout Europe and more recently in Canada. Funding statement: From 2009–2014, the BALTRAD and BALTRAD+ projects were part-financed by the European Union (European Regional Development Fund and European Neighbourhood and Partnership Instrument, with project numbers #009 and #101, respectively.

  11. Doppler Radar Vital Signs Detection Method Based on Higher Order Cyclostationary.

    Science.gov (United States)

    Yu, Zhibin; Zhao, Duo; Zhang, Zhiqiang

    2017-12-26

    Due to the non-contact nature, using Doppler radar sensors to detect vital signs such as heart and respiration rates of a human subject is getting more and more attention. However, the related detection-method research meets lots of challenges due to electromagnetic interferences, clutter and random motion interferences. In this paper, a novel third-order cyclic cummulant (TOCC) detection method, which is insensitive to Gaussian interference and non-cyclic signals, is proposed to investigate the heart and respiration rate based on continuous wave Doppler radars. The k -th order cyclostationary properties of the radar signal with hidden periodicities and random motions are analyzed. The third-order cyclostationary detection theory of the heart and respiration rate is studied. Experimental results show that the third-order cyclostationary approach has better estimation accuracy for detecting the vital signs from the received radar signal under low SNR, strong clutter noise and random motion interferences.

  12. Translation compensation and micro-Doppler extraction for precession ballistic targets with a wideband terahertz radar

    Science.gov (United States)

    Yang, Qi; Deng, Bin; Wang, Hongqiang; Zhang, Ye; Qin, Yuliang

    2018-01-01

    Imaging, classification, and recognition techniques of ballistic targets in midcourse have always been the focus of research in the radar field for military applications. However, the high velocity translation of ballistic targets will subject range profile and Doppler to translation, slope, and fold, which are especially severe in the terahertz region. Therefore, a two-step translation compensation method based on envelope alignment is presented. The rough compensation is based on the traditional envelope alignment algorithm in inverse synthetic aperture radar imaging, and the fine compensation is supported by distance fitting. Then, a wideband imaging radar system with a carrier frequency of 0.32 THz is introduced, and an experiment on a precession missile model is carried out. After translation compensation with the method proposed in this paper, the range profile and the micro-Doppler distributions unaffected by translation are obtained, providing an important foundation for the high-resolution imaging and micro-Doppler extraction of the terahertz radar.

  13. A Novel Motion Compensation Method for Random Stepped Frequency Radar with M-sequence

    Science.gov (United States)

    Liao, Zhikun; Hu, Jiemin; Lu, Dawei; Zhang, Jun

    2018-01-01

    The random stepped frequency radar is a new kind of synthetic wideband radar. In the research, it has been found that it possesses a thumbtack-like ambiguity function which is considered to be the ideal one. This also means that only a precise motion compensation could result in the correct high resolution range profile. In this paper, we will introduce the random stepped frequency radar coded by M-sequence firstly and briefly analyse the effect of relative motion between target and radar on the distance imaging, which is called defocusing problem. Then, a novel motion compensation method, named complementary code cancellation, will be put forward to solve this problem. Finally, the simulated experiments will demonstrate its validity and the computational analysis will show up its efficiency.

  14. Space Radar Image of Chernobyl

    Science.gov (United States)

    1994-01-01

    This is an image of the Chernobyl nuclear power plant and its surroundings, centered at 51.17 north latitude and 30.15 west longitude. The image was acquired by the Spaceborne Imaging Radar-C and X-band Synthetic Aperture Radar aboard the space shuttle Endeavour on its 16th orbit on October 1, 1994. The area is located on the northern border of the Ukraine Republic and was produced by using the L-band (horizontally transmitted and received) polarization. The differences in the intensity are due to differences in vegetation cover, with brighter areas being indicative of more vegetation. These data were acquired as part of a collaboration between NASA and the National Space Agency of Ukraine in Remote Sensing and Earth Sciences. NASA has included several sites provided by the Ukrainian space agency as targets of opportunity during the second flight of SIR-C/X-SAR. The Ukrainian space agency also plans to conduct airborne surveys of these sites during the mission. The Chernobyl nuclear power plant is located toward the top of the image near the Pripyat River. The 12-kilometer (7.44-mile)-long cooling pond is easily distinguishable as an elongated dark shape in the center near the top of the image. The reactor complex is visible as the bright area to the extreme left of the cooling pond and the city of Chernobyl is the bright area just below the cooling pond next to the Pripyat River. The large dark area in the bottom right of the image is the Kiev Reservoir just north of Kiev. Also visible is the Dnieper River, which feeds into the Kiev Reservoir from the top of the image. The Soviet government evacuated 116,000 people within 30 kilometers (18.6 miles) of the Chernobyl reactor after the explosion and fire on April 26, 1986. Spaceborne Imaging Radar-C and X-band Synthetic Aperture Radar (SIR-C/X-SAR) is part of NASA's Mission to Planet Earth. The radars illuminate Earth with microwaves, allowing detailed observations at any time, regardless of weather or sunlight

  15. Radar

    DEFF Research Database (Denmark)

    Nielsen, Tom

    2009-01-01

    Bidrag til arkitektens opgørelse (baseret på en række forskellige indlæg) over hvor dansk arkitektur står, med korte bud på spørgsmålene: Kan man ud over stedsanknytningen tale om en særlig dansk arkitektur?, Hvad er dansk arkitekturs største kvalitet, vores vigtigste force? og Hvad er dansk arki...

  16. Closed form fourier-based transmit beamforming for MIMO radar

    KAUST Repository

    Lipor, John J.

    2014-05-01

    In multiple-input multiple-output (MIMO) radar setting, it is often desirable to design correlated waveforms such that power is transmitted only to a given set of locations, a process known as beampattern design. To design desired beam-pattern, current research uses iterative algorithms, first to synthesize the waveform covariance matrix, R, then to design the actual waveforms to realize R. In contrast to this, we present a closed form method to design R that exploits discrete Fourier transform and Toeplitz matrix. The resulting covariance matrix fulfills the practical constraints and performance is similar to that of iterative methods. Next, we present a radar architecture for the desired beampattern that does not require the synthesis of covariance matrix nor the design of correlated waveforms. © 2014 IEEE.

  17. Surface Current Measurements In Terra Nova Bay By Hf Radar

    Science.gov (United States)

    Flocco, D.; Falco, P.; Wadhams, P.; Spezie, G.

    We present the preliminary results of a field experiment carried out within frame- work of the CLIMA project of the Italian National Programme for Antarctic Research (PNRA) and in cooperation with the Scott Polar Research Institute of Cambridge. Dur- ing the second period (02/12/1999-23/01/2000) of the XV Italian expedition a coastal radar was used to characterize the current field in the area of Terra Nova Bay (TNB). One of the aims of the CLIMA (Climatic Long-term Interactions for the Mass balance in Antarctica) project is to determine the role of the polynya in the sea ice mass bal- ance, water structure and local climate. The OSCR-II experiment was planned in order to provide surface current measurements in the area of TNB polynya, one of the most important coastal polynya of the Ross Sea. OSCR (Ocean Surface Current Radar) is a shore based, remote sensing system designed to measure sea surface currents in coastal waters. Two radar sites (a master and a slave) provide with radial current mea- surements; data combined from both sites yield the total current vector. Unfortunately the master and slave stations did not work together throughout the whole period of the experiment. A description of the experiment and a discussion of the results, will be proposed.

  18. Radar-based rainfall estimation: Improving Z/R relations through comparison of drop size distributions, rainfall rates and radar reflectivity patterns

    Science.gov (United States)

    Neuper, Malte; Ehret, Uwe

    2014-05-01

    The relation between the measured radar reflectivity factor Z and surface rainfall intensity R - the Z/R relation - is profoundly complex, so that in general one speaks about radar-based quantitative precipitation estimation (QPE) rather than exact measurement. Like in Plato's Allegory of the Cave, what we observe in the end is only the 'shadow' of the true rainfall field through a very small backscatter of an electromagnetic signal emitted by the radar, which we hope has been actually reflected by hydrometeors. The meteorological relevant and valuable Information is gained only indirectly by more or less justified assumptions. One of these assumptions concerns the drop size distribution, through which the rain intensity is finally associated with the measured radar reflectivity factor Z. The real drop size distribution is however subject to large spatial and temporal variability, and consequently so is the true Z/R relation. Better knowledge of the true spatio-temporal Z/R structure therefore has the potential to improve radar-based QPE compared to the common practice of applying a single or a few standard Z/R relations. To this end, we use observations from six laser-optic disdrometers, two vertically pointing micro rain radars, 205 rain gauges, one rawindsonde station and two C-band Doppler radars installed or operated in and near the Attert catchment (Luxembourg). The C-band radars and the rawindsonde station are operated by the Belgian and German Weather Services, the rain gauge data was partly provided by the French, Dutch, Belgian, German Weather Services and the Ministry of Agriculture of Luxembourg and the other equipment was installed as part of the interdisciplinary DFG research project CAOS (Catchment as Organized Systems). With the various data sets correlation analyzes were executed. In order to get a notion on the different appearance of the reflectivity patterns in the radar image, first of all various simple distribution indices (for example the

  19. New look at radar auroral motions

    International Nuclear Information System (INIS)

    Greenwald, R.A.; Ecklund, W.L.

    1975-01-01

    During October 1974, three modifications were temporarily added to the NOAA radar auroral backscatter facility located at Anchorage, Alaska. These modifications included (1) a multiple azimuth antenna system. (2) an on-line computer for processing amplitude and mean Doppler profiles of the radar backscatter, and (3) a 13-baud Barker coder. In combination with the radar these modifications provided data relevant to understanding both the microscopic and the macroscopic nature of the radar aurora. Appreciable structure was often found in the Doppler velocity profiles of radar auroral irregularities. Doppler velocities of nearly 2000 m/s were observed. By combining scatter amplitude profiles and mean Doppler profiles from the five azimuths we have produced contour maps of the scatter intensity and the Doppler velocity. The scatter intensity maps often indicate appreciable temporal and spatial structure in the radar auroral irregularities, corroborating the results of Tsunoda et al. (1974). The mean Doppler contour maps indicate that there is also appreciable temporal and spatial structure in the flow velocities of radar auroral irregularities. At those times when there appears to be large-scale uniformity in the irregularity flow, the Doppler velocity varies with azimuth in a manner that is consistent with a cosine-dependent azimuthal variation

  20. Condor equatorial electrojet campaign: Radar results

    International Nuclear Information System (INIS)

    Kudeki, E.; Fejer, B.G.; Farley, D.T.; Hanuise, C.

    1987-01-01

    A review of the experimental and theoretical background to the Condor equatorial electrojet compaign is followed by the presentation and discussion of VHF radar interferometer and HF radar backscatter data taken concurrently with two rocket in situ experiments reported in companion papers (Pfaff et al., this issue (a, b). Both experiments were conducted in strongly driven periods with the on-line radar interferometer displaying signatures of what has been interpreted in earlier radar work (Kudeki et al., 1982) as kilometer scale gradient drift waves. Low-frequency density fluctuations detected by in situ rocket sensors confirm the earlier interpretation. VHF radar/rocket data comparisons also indicate the existence of a turbulent layer in the upper portion of the daytime electrojet at about 108 km altitude driven purely by the two-stream instability. Nonlinear mode coupling of linearly growing two-stream waves to linearly damped 3-m vertical modes could account for the radar echoes scattered from this layer, which showed no indication of large-scale gradient drift waves. Nonlinear mode coupling may therefore compete with the wave-induced anomalous diffusion mechanism proposed recently by Sudan (1983) for the saturation of directly excited two-stream waves. Nighttime radar data show a bifurcated layer with the two parts having comparable echo strength but oppositely directed zonal drift velocities. The lower layer shows narrow backscatter spectra; the upper layer is characterized by kilometer scale waves and vertically propagating type 1 waves

  1. Using phase for radar scatterer classification

    Science.gov (United States)

    Moore, Linda J.; Rigling, Brian D.; Penno, Robert P.; Zelnio, Edmund G.

    2017-04-01

    Traditional synthetic aperture radar (SAR) systems tend to discard phase information of formed complex radar imagery prior to automatic target recognition (ATR). This practice has historically been driven by available hardware storage, processing capabilities, and data link capacity. Recent advances in high performance computing (HPC) have enabled extremely dense storage and processing solutions. Therefore, previous motives for discarding radar phase information in ATR applications have been mitigated. First, we characterize the value of phase in one-dimensional (1-D) radar range profiles with respect to the ability to correctly estimate target features, which are currently employed in ATR algorithms for target discrimination. These features correspond to physical characteristics of targets through radio frequency (RF) scattering phenomenology. Physics-based electromagnetic scattering models developed from the geometrical theory of diffraction are utilized for the information analysis presented here. Information is quantified by the error of target parameter estimates from noisy radar signals when phase is either retained or discarded. Operating conditions (OCs) of signal-tonoise ratio (SNR) and bandwidth are considered. Second, we investigate the value of phase in 1-D radar returns with respect to the ability to correctly classify canonical targets. Classification performance is evaluated via logistic regression for three targets (sphere, plate, tophat). Phase information is demonstrated to improve radar target classification rates, particularly at low SNRs and low bandwidths.

  2. Forensic Application of FM-CW and Pulse Radar

    Energy Technology Data Exchange (ETDEWEB)

    S. K. Koppenjan; R. S. Freeland; M. L. Miller; R. E. Yoder

    2003-01-01

    Ground-penetrating radar (GPR) technology has supplied vital assistance in criminal investigations. However, law enforcement personnel desire further developments such that the technology is rapidly deployable, and that it provides both a simple user interface and sophisticated target identification. To assist in the development of target identification algorithms, our efforts involve gathering background GPR data for the various site conditions and circumstances that often typify clandestine burials. For this study, forensic anthropologists established shallow-grave plots at The University of Tennessee Anthropological Research Facility (ARF) that are specific to GPR research. These plots contain donated human cadavers lying in various configurations and depths, surrounded by assorted construction material and backfill debris. We scanned the plots using two GPR technologies: (1) a multi-frequency synthetic-aperture FM-CW radar (200-700 MHz) (GPR-X) developed by the U.S. Department of Energy's (DOE) Special Technologies Laboratory (STL), Bechtel Nevada (Koppenjan et al., 2000), and (2) a commercial pulse radar (SIR-20) manufactured by Geophysical Survey Systems, Inc. (400 and 900 MHz)(GSSI). The sweep-frequency data show the large biological mass decomposing within the torso as encircled ''hot spots.'' The 400-MHz pulse radar exhibit major horizontal reflectors above the body, with shadow reflectors (horizontal multiples) occurring beneath the body at 60 cm depth. The 400-MHz antenna was able to discern the grave walls and folded tarp covering the lower body. Under these moist, clay-rich conditions, the 900-MHz antenna was able to penetrate slightly beyond 30 cm beneath the concrete layer. However, neither system was able to penetrate beyond a one meter depth in the moist, clay-rich soil (fine, mixed, thermic Typic Paleudalf). Example scans from each system are provided, along with a discussion of the survey protocol and general performance.

  3. Foliage penetration radar detection and characterization of objects under trees

    CERN Document Server

    Davis, Mark

    2011-01-01

    This book covers all aspects of foliage penetration (FOPEN) radar, concentrating on both airborne military radar systems as well as earth resource mapping radars. It is the first concise and thorough treatment of FOPEN, covering the results of a decade-long investment by DARPA in characterizing foliage and earth surface with ultrawideband UHF and VHF synthetic aperture radar (SAR).

  4. The use of radar for bathymetry in shallow seas

    NARCIS (Netherlands)

    Greidanus, H.

    1997-01-01

    The bottom topography in shallow seas can be observed by air- and space borne radar. The paper reviews the radar imaging mechanism, and discusses the possibilities and limitations for practical use of radar in bathymetric applications, including the types of radar instruments available for this

  5. Radar ornithology and the conservation of migratory birds

    Science.gov (United States)

    Sidney A. Gauthreaux; Carroll G. Belser

    2005-01-01

    It is possible to study with surveillance radar the movements of migrating birds in the atmosphere at different spatial scales. At a spatial scale within a range of 6 kilometers, high-resolution, 3-centimeter wavelength surveillance radar (e.g. BIRDRAD) can detect the departure of migrants from different types of habitat within a few kilometers of the radar. The radar...

  6. Radar Image with Color as Height, Sman Teng, Temple, Cambodia

    Science.gov (United States)

    2002-01-01

    This image of Cambodia's Angkor region, taken by NASA's Airborne Synthetic Aperture Radar (AIRSAR), reveals a temple (upper-right) not depicted on early 19th Century French archeological survey maps and American topographic maps. The temple, known as 'Sman Teng,' was known to the local Khmer people, but had remained unknown to historians due to the remoteness of its location. The temple is thought to date to the 11th Century: the heyday of Angkor. It is an important indicator of the strategic and natural resource contributions of the area northwest of the capitol, to the urban center of Angkor. Sman Teng, the name designating one of the many types of rice enjoyed by the Khmer, was 'discovered' by a scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif., working in collaboration with an archaeological expert on the Angkor region. Analysis of this remote area was a true collaboration of archaeology and technology. Locating the temple of Sman Teng required the skills of scientists trained to spot the types of topographic anomalies that only radar can reveal.This image, with a pixel spacing of 5 meters (16.4 feet), depicts an area of approximately 5 by 4.7 kilometers (3.1 by 2.9 miles). North is at top. Image brightness is from the P-band (68 centimeters, or 26.8 inches) wavelength radar backscatter, a measure of how much energy the surface reflects back toward the radar. Color is used to represent elevation contours. One cycle of color represents 25 meters (82 feet) of elevation change, so going from blue to red to yellow to green and back to blue again corresponds to 25 meters (82 feet) of elevation change.AIRSAR flies aboard a NASA DC-8 based at NASA's Dryden Flight Research Center, Edwards, Calif. In the TOPSAR mode, AIRSAR collects radar interferometry data from two spatially separated antennas (2.6 meters, or 8.5 feet). Information from the two antennas is used to form radar backscatter imagery and to generate highly accurate elevation data. Built

  7. Integrated High-Speed Digital Optical True-Time-Delay Modules for Synthetic Aperture Radars, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Crystal Research, Inc. proposes an integrated high-speed digital optical true-time-delay module for advanced synthetic aperture radars. The unique feature of this...

  8. Radar Exploration of Cometary Nuclei

    Science.gov (United States)

    Gim, Yonggyu; Heggy, E.; Belton, M.; Weissman, P.; Asphaug, E.

    2012-10-01

    We have developed a mission formulation, based on the use of previously flown planetary radar sounding techniques, to image the 3D internal structure of the nucleus of a Jupiter-family comet (JFC). Believed to originate in the outer solar system and to be delivered recently to the inner solar system from the Kuiper Belt, JFCs are among the most primitive bodies accessible by spacecraft, and are indicated in the 2010 Decadal Survey as primary targets for primitive bodies sample return. We consider a sounder design operating at dual frequencies, 5 and 15 MHz center frequencies with 1 and 10 MHz bandwidths, respectively. Operating from close orbit about the nucleus of a spinning comet nucleus, CORE obtains a dense network of echoes that are used to image its interior structure to 10 m and to map the dielectric properties inside the nucleus to better than 200 m throughout. Clear images of internal structure and dielectric composition will reveal how the nucleus was formed and how it has evolved. Radiometric tracking of the spacecraft orbit will provide an interior mass distribution that constrains the radar-based models of interior composition. High-resolution visible and infrared color images provide surface and exterior boundary conditions for interior models and hypotheses. They present the geology and morphology of the nucleus surface at meter-scales, and the time-evolving activity, structure, and composition of the inner coma. By making global yet detailed connections from interior to exterior, the data from CORE will provide answers to fundamental questions about the earliest stages of planetesimal evolution and planet formation, will be an important complement to the Rosetta mission science, and will lay the foundation for comet nucleus sample return.

  9. Radar, sonar, and holography an introduction

    CERN Document Server

    Kock, Winston E

    1974-01-01

    Radar, Sonar, and Holography: An Introduction provides an introduction to the technology of radar and sonar. Because the new science of holography is affecting both these fields quite strongly, the book includes an explanation of the fundamental principles underlying this new art (including the subjects of wave coherence, interference, and diffraction) and of the hologram process itself. Finally, numerous examples are discussed which show how holography is providing new horizons to radar and sonar systems. The book thus also provides a simple approach to the new technology of holography. The

  10. Image Registration Methode in Radar Interferometry

    Directory of Open Access Journals (Sweden)

    S. Chelbi

    2015-08-01

    Full Text Available This article presents a methodology for the determination of the registration of an Interferometric Synthetic radar (InSAR pair images with half pixel precision. Using the two superposed radar images Single Look complexes (SLC [1-4], we developed an iterative process to superpose these two images according to their correlation coefficient with a high coherence area. This work concerns the exploitation of ERS Tandem pair of radar images SLC of the Algiers area acquired on 03 January and 04 January 1994. The former is taken as a master image and the latter as a slave image.

  11. Signal compression in radar using FPGA

    OpenAIRE

    Enrique Escamilla Hemández; Víctor Kravchenko; Volodymyr Ponomaryov; Gonzalo Duchen Sánchez; David Hernández Sánchez

    2010-01-01

    El presente artículo muestra la puesta en práctica de hardware para realizar el procesamiento en tiempo real de la señal de radar usando una técnica simple, rápida basada en arquitectura de FPGA (Field Programmable Gate Array). El proceso incluye diversos procedimientos de enventanado durante la compresión del pulso del radar de apertura sintética (SAR). El proceso de compresión de la señal de radar se hace con un filtro acoplado. que aplica funciones clásicas y nuevas de enventanado, donde n...

  12. Radar orthogonality and radar length in Finsler and metric spacetime geometry

    Science.gov (United States)

    Pfeifer, Christian

    2014-09-01

    The radar experiment connects the geometry of spacetime with an observers measurement of spatial length. We investigate the radar experiment on Finsler spacetimes which leads to a general definition of radar orthogonality and radar length. The directions radar orthogonal to an observer form the spatial equal time surface an observer experiences and the radar length is the physical length the observer associates to spatial objects. We demonstrate these concepts on a forth order polynomial Finsler spacetime geometry which may emerge from area metric or premetric linear electrodynamics or in quantum gravity phenomenology. In an explicit generalization of Minkowski spacetime geometry we derive the deviation from the Euclidean spatial length measure in an observers rest frame explicitly.

  13. Investigating hydrocarbon contamination using ground penetrating radar

    International Nuclear Information System (INIS)

    Roest, P.B. van der; Brasser, D.J.S.; Wagebaert, A.P.J.; Stam, P.H.

    1996-01-01

    The increasing costs of remediating contaminated sites has stimulated research for cost reducing techniques in soil investigation and clean-up techniques. Under the traditional approach soil borings and groundwater wells are used to investigate contaminated soil. These are useful tools to determine the amount and characteristics of the contamination, but they are inefficient and costly in providing information on the location and extent of contamination as they only give information on one point. This often leads to uncertainty in estimating clean-up costs or, even worse, to unsuccessful clean-ups. MAP Environmental Research has developed a technology using Ground Penetrating Radar (GPR) in combination with in-house developed software to locate and define the extent of hydrocarbon contamination. With this technology, the quality of site investigation is increased while costs are reduced. Since 1994 MAP has been improving its technology and has applied it to over 100 projects, which all have been checked afterwards by conventional drilling. This paper gives some general characteristics of the method and presents a case study. The emphasis of this paper lies on the practical application of GPR to hydrocarbon contamination detection

  14. Effects of Atmospheric Refraction on an Airborne Weather Radar Detection and Correction Method

    Directory of Open Access Journals (Sweden)

    Lei Wang

    2015-01-01

    Full Text Available This study investigates the effect of atmospheric refraction, affected by temperature, atmospheric pressure, and humidity, on airborne weather radar beam paths. Using three types of typical atmospheric background sounding data, we established a simulation model for an actual transmission path and a fitted correction path of an airborne weather radar beam during airplane take-offs and landings based on initial flight parameters and X-band airborne phased-array weather radar parameters. Errors in an ideal electromagnetic beam propagation path are much greater than those of a fitted path when atmospheric refraction is not considered. The rates of change in the atmospheric refraction index differ with weather conditions and the radar detection angles differ during airplane take-off and landing. Therefore, the airborne radar detection path must be revised in real time according to the specific sounding data and flight parameters. However, an error analysis indicates that a direct linear-fitting method produces significant errors in a negatively refractive atmosphere; a piecewise-fitting method can be adopted to revise the paths according to the actual atmospheric structure. This study provides researchers and practitioners in the aeronautics and astronautics field with updated information regarding the effect of atmospheric refraction on airborne weather radar detection and correction methods.

  15. Meteorite Fall Detection and Analysis via Weather Radar: Worldwide Potential for Citizen Science

    Science.gov (United States)

    Fries, M.; Bresky, C.; Laird, C.; Reddy, V.; Hankey, M.

    2017-12-01

    Meteorite falls can be detected using weather radars, facilitating rapid recovery of meteorites to minimize terrestrial alteration. Imagery from the US NEXRAD radar network reveals over two dozen meteorite falls where meteorites have been recovered, and about another dozen that remain unrecovered. Discovery of new meteorite falls is well suited to "citizen science" and similar outreach activities, as well as automation of computational components into internet-based search tools. Also, there are many more weather radars employed worldwide than those in the US NEXRAD system. Utilization of weather radars worldwide for meteorite recovery can not only expand citizen science opportunities but can also lead to significant improvement in the number of freshly-fallen meteorites available for research. We will discuss the methodologies behind locating and analyzing meteorite falls using weather radar, and how to make them available for citizen science efforts. An important example is the Aquarius Project, a Chicago-area consortium recently formed with the goal of recovering meteorites from Lake Michigan. This project has extensive student involvement geared toward development of actual hardware for recovering meteorites from the lake floor. Those meteorites were identified in weather radar imagery as they fell into the lake from a large meteor on 06 Feb 2017. Another example of public interaction is the meteor detection systems operated by the American Meteor Society (AMS). The AMS website has been developed to allow public reporting of meteors, effectively enabling citizen science to locate and describe significant meteor events worldwide.

  16. A Two-Stage Reconstruction Processor for Human Detection in Compressive Sensing CMOS Radar.

    Science.gov (United States)

    Tsao, Kuei-Chi; Lee, Ling; Chu, Ta-Shun; Huang, Yuan-Hao

    2018-04-05

    Complementary metal-oxide-semiconductor (CMOS) radar has recently gained much research attraction because small and low-power CMOS devices are very suitable for deploying sensing nodes in a low-power wireless sensing system. This study focuses on the signal processing of a wireless CMOS impulse radar system that can detect humans and objects in the home-care internet-of-things sensing system. The challenges of low-power CMOS radar systems are the weakness of human signals and the high computational complexity of the target detection algorithm. The compressive sensing-based detection algorithm can relax the computational costs by avoiding the utilization of matched filters and reducing the analog-to-digital converter bandwidth requirement. The orthogonal matching pursuit (OMP) is one of the popular signal reconstruction algorithms for compressive sensing radar; however, the complexity is still very high because the high resolution of human respiration leads to high-dimension signal reconstruction. Thus, this paper proposes a two-stage reconstruction algorithm for compressive sensing radar. The proposed algorithm not only has lower complexity than the OMP algorithm by 75% but also achieves better positioning performance than the OMP algorithm especially in noisy environments. This study also designed and implemented the algorithm by using Vertex-7 FPGA chip (Xilinx, San Jose, CA, USA). The proposed reconstruction processor can support the 256 × 13 real-time radar image display with a throughput of 28.2 frames per second.

  17. Dynamic Gesture Recognition with a Terahertz Radar Based on Range Profile Sequences and Doppler Signatures.

    Science.gov (United States)

    Zhou, Zhi; Cao, Zongjie; Pi, Yiming

    2017-12-21

    The frequency of terahertz radar ranges from 0.1 THz to 10 THz, which is higher than that of microwaves. Multi-modal signals, including high-resolution range profile (HRRP) and Doppler signatures, can be acquired by the terahertz radar system. These two kinds of information are commonly used in automatic target recognition; however, dynamic gesture recognition is rarely discussed in the terahertz regime. In this paper, a dynamic gesture recognition system using a terahertz radar is proposed, based on multi-modal signals. The HRRP sequences and Doppler signatures were first achieved from the radar echoes. Considering the electromagnetic scattering characteristics, a feature extraction model is designed using location parameter estimation of scattering centers. Dynamic Time Warping (DTW) extended to multi-modal signals is used to accomplish the classifications. Ten types of gesture signals, collected from a terahertz radar, are applied to validate the analysis and the recognition system. The results of the experiment indicate that the recognition rate reaches more than 91%. This research verifies the potential applications of dynamic gesture recognition using a terahertz radar.

  18. A Two-Stage Reconstruction Processor for Human Detection in Compressive Sensing CMOS Radar

    Directory of Open Access Journals (Sweden)

    Kuei-Chi Tsao

    2018-04-01

    Full Text Available Complementary metal-oxide-semiconductor (CMOS radar has recently gained much research attraction because small and low-power CMOS devices are very suitable for deploying sensing nodes in a low-power wireless sensing system. This study focuses on the signal processing of a wireless CMOS impulse radar system that can detect humans and objects in the home-care internet-of-things sensing system. The challenges of low-power CMOS radar systems are the weakness of human signals and the high computational complexity of the target detection algorithm. The compressive sensing-based detection algorithm can relax the computational costs by avoiding the utilization of matched filters and reducing the analog-to-digital converter bandwidth requirement. The orthogonal matching pursuit (OMP is one of the popular signal reconstruction algorithms for compressive sensing radar; however, the complexity is still very high because the high resolution of human respiration leads to high-dimension signal reconstruction. Thus, this paper proposes a two-stage reconstruction algorithm for compressive sensing radar. The proposed algorithm not only has lower complexity than the OMP algorithm by 75% but also achieves better positioning performance than the OMP algorithm especially in noisy environments. This study also designed and implemented the algorithm by using Vertex-7 FPGA chip (Xilinx, San Jose, CA, USA. The proposed reconstruction processor can support the 256 × 13 real-time radar image display with a throughput of 28.2 frames per second.

  19. Empirical Soil Moisture Estimation with Spaceborne L-band Polarimetric Radars: Aquarius, SMAP, and PALSAR-2

    Science.gov (United States)

    Burgin, M. S.; van Zyl, J. J.

    2017-12-01

    Traditionally, substantial ancillary data is needed to parametrize complex electromagnetic models to estimate soil moisture from polarimetric radar data. The Soil Moisture Active Passive (SMAP) baseline radar soil moisture retrieval algorithm uses a data cube approach, where a cube of radar backscatter values is calculated using sophisticated models. In this work, we utilize the empirical approach by Kim and van Zyl (2009) which is an optional SMAP radar soil moisture retrieval algorithm; it expresses radar backscatter of a vegetated scene as a linear function of soil moisture, hence eliminating the need for ancillary data. We use 2.5 years of L-band Aquarius radar and radiometer derived soil moisture data to determine two coefficients of a linear model function on a global scale. These coefficients are used to estimate soil moisture with 2.5 months of L-band SMAP and L-band PALSAR-2 data. The estimated soil moisture is compared with the SMAP Level 2 radiometer-only soil moisture product; the global unbiased RMSE of the SMAP derived soil moisture corresponds to 0.06-0.07 cm3/cm3. In this study, we leverage the three diverse L-band radar data sets to investigate the impact of pixel size and pixel heterogeneity on soil moisture estimation performance. Pixel sizes range from 100 km for Aquarius, over 3, 9, 36 km for SMAP, to 10m for PALSAR-2. Furthermore, we observe seasonal variation in the radar sensitivity to soil moisture which allows the identification and quantification of seasonally changing vegetation. Utilizing this information, we further improve the estimation performance. The research described in this paper is supported by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Copyright 2017. All rights reserved.

  20. Very high latitude F-region irregularities observed by HF-radar backscatter

    International Nuclear Information System (INIS)

    Baker, K.B.; Greenwald, R.A.; Tsunoda, R.T.

    1983-01-01

    In February and March, 1982, a coherent scatter HF radar was operated from Cleary, Alaska to observe 7- to 15-m wavelength F-region plasma irregularities near the poleward edge of the auroral zone and in the polar cap. The radar operated for five days from February 25 to March 1 and produced approximately 700,000 Doppler spectra during that time. Of those nearly 700,000 spectra, approximately 10% showed backscattered power 3 dB or more above the noise level. A ray tracing technique using electron densities determined by the Chatanika incoherent scatter radar was used to predict locations where the HF waves were approximately normal to the magnetic field. If those locations were also to contain small scale electron density structure, then one would expect them to backscatter the HF waves. Several comparisons were made between predicted and observed locations of radiowave backscatter and excellent agreement was obtained. In addition, comparisons of the Doppler velocities observed by the coherent scatter HF radar and those observed by the Chatanika radar showed good agreement, suggesting that the plasma irregularities observed by the HF radar drift with the ambient plasma. In addition, average vector velocities calculated for the entire 5-day period show a flow pattern consistent with polar cap convection models. This again indicates that the irregularities drift with the plasma, as is predicted by a number of theories of F-region plasma irregularities. In the summer of 1983, the research program begun with those measurements will be continued with a steerable phased-array HF radar located at Goose Bay, Labrador, that will view the same ionospheric region as does the Sondre Stromfjord incoherent scatter radar

  1. Development Of Signal Detection For Radar Navigation System

    OpenAIRE

    Theingi Win Hlaing; Hla Myo Tun; Zaw Min Naing; Win Khaing Moe

    2017-01-01

    This paper aims to evaluate the performance of target detection in the presence of sea clutter. Radar detection of a background of unwanted clutter due to echoes from sea clutter or land is a problem of interest in the radar field. Radar detector has been developed by assuming the radar clutter is Gaussian distributed. However as technology emerges the radar distribution is seen to deviates from the Gaussian assumption. Thus detectors designs based on Gaussian assumption are no longer optimum...

  2. Radar Polarimetry and Interferometry (La polarimetrie et l'interferometrie radar) (CD-ROM)

    National Research Council Canada - National Science Library

    Keydel, W; Boerner, W. M; Pottier, E; Lee, J. S; Ferro-Famil, L; Hellmann, M; Cloude, S. R

    2005-01-01

    ...: Scientists and engineers already engaged in the fields of radar surveillance, reconnaissance and scattering measurements, for instance, generally gain their specialist knowledge in both polarimetry...

  3. Synthetic impulse and aperture radar (SIAR) a novel multi-frequency MIMO radar

    CERN Document Server

    Chen, Baixiao

    2014-01-01

    Analyzes and discusses the operating principle, signal processing method, and experimental results of this advanced radar technology This book systematically discusses the operating principle, signal processing method, target measurement technology, and experimental results of a new kind of radar called synthetic impulse and aperture radar (SIAR). The purpose is to help readers acquire an insight into the concept and principle of the SIAR, to know its operation mode, signal processing method, the difference between the traditional radar and itself, the designing ideals, and the developing me

  4. Flood Monitoring using X-band Dual-polarization Radar Network

    Science.gov (United States)

    Chandrasekar, V.; Wang, Y.; Maki, M.; Nakane, K.

    2009-09-01

    sensitivity and fast temporal update across the coverage. Strong clutter is expected from buildings in the neighborhood which act as perfect reflectors. The reduction in radar size enables flexible deployment, such as rooftop installation, with small infrastructure requirement, which is critical in a metropolitan region. Dual-polarization based technologies can be implemented for real-time mitigation of rain attenuations and accurate estimation of rainfall. The NSF Engineering Research Center for Collaborative Adaptive Sensing of the Atmosphere (CASA) is developing the technologies and the systems for network centric weather observation. The Differential propagation phase (Kdp) has higher sensitivity at X-band compared to S and C band. It is attractive to use Kdp to derive Quantitative Precipitation Estimation (QPE) because it is immune to rain attenuation, calibration biases, partial beam blockage, and hail contamination. Despite the advantage of Kdp for radar QPE, the estimation of Kdp itself is a challenge as the range derivative of the differential propagation phase profiles. An adaptive Kdp algorithm was implemented in the CASA IP1 testbed that substantially reduces the fluctuation in light rain and the bias at heavy rain. The Kdp estimation also benefits from the higher resolution in the IP1 radar network. The performance of the IP1 QPE product was evaluated for all major rain events against the USDA Agriculture Research Service's gauge network (MicroNet) in the Little Washita watershed, which comprises 20 weather stations in the center of the test bed. The cross-comparison with gauge measurements shows excellent agreement for the storm events during the Spring Experiments of 2007 and 2008. The hourly rainfall estimates compared to the gauge measurements have a very small bias of few percent and a normalized standard error of 21%. The IP1 testbed was designed with overlapping coverage among its radar nodes. The study area is covered by multiple radars and the aspect of

  5. Radar-based collision avoidance for unmanned surface vehicles

    Science.gov (United States)

    Zhuang, Jia-yuan; Zhang, Lei; Zhao, Shi-qi; Cao, Jian; Wang, Bo; Sun, Han-bing

    2016-12-01

    Unmanned surface vehicles (USVs) have become a focus of research because of their extensive applications. To ensure safety and reliability and to perform complex tasks autonomously, USVs are required to possess accurate perception of the environment and effective collision avoidance capabilities. To achieve these, investigation into realtime marine radar target detection and autonomous collision avoidance technologies is required, aiming at solving the problems of noise jamming, uneven brightness, target loss, and blind areas in marine radar images. These technologies should also satisfy the requirements of real-time and reliability related to high navigation speeds of USVs. Therefore, this study developed an embedded collision avoidance system based on the marine radar, investigated a highly real-time target detection method which contains adaptive smoothing algorithm and robust segmentation algorithm, developed a stable and reliable dynamic local environment model to ensure the safety of USV navigation, and constructed a collision avoidance algorithm based on velocity obstacle (V-obstacle) which adjusts the USV's heading and speed in real-time. Sea trials results in multi-obstacle avoidance firstly demonstrate the effectiveness and efficiency of the proposed avoidance system, and then verify its great adaptability and relative stability when a USV sailing in a real and complex marine environment. The obtained results will improve the intelligent level of USV and guarantee the safety of USV independent sailing.

  6. Radar data processing using a distributed computational system

    Science.gov (United States)

    Mota, Gilberto F.

    1992-06-01

    This research specifies and validates a new concurrent decomposition scheme, called Confined Space Search Decomposition (CSSD), to exploit parallelism of Radar Data Processing algorithms using a Distributed Computational System. To formalize the specification, we propose and apply an object-oriented methodology called Decomposition Cost Evaluation Model (DCEM). To reduce the penalties of load imbalance, we propose a distributed dynamic load balance heuristic called Object Reincarnation (OR). To validate the research, we first compare our decomposition with an identified alternative using the proposed DCEM model and then develop a theoretical prediction of selected parameters. We also develop a simulation to check the Object Reincarnation Concept.

  7. Greenland Radar Ice Sheet Thickness Measurements

    Data.gov (United States)

    National Aeronautics and Space Administration — Two 150-MHz coherent radar depth sounders were developed and flown over the Greenland ice sheet to obtain ice thickness measurements in support of PARCA...

  8. Identifying structural damage with ground penetrating radar

    CSIR Research Space (South Africa)

    Van Schoor, Abraham M

    2008-07-01

    Full Text Available Ground penetrating radar (GPR) and electrical resistance tomography (ERT) surveys were conducted in an urban environment in an attempt to identify the cause of severe structural damage to a historically significant residential property...

  9. Simulating lightning tests to radar system

    NARCIS (Netherlands)

    Blaj, M.A.; Buesink, Frederik Johannes Karel; Leferink, Frank Bernardus Johannes

    2010-01-01

    The risk of destruction due to lightning makes simulating the effects of lightning strikes a necessity. We modeled a radar enclosure and simulated the effect of a lightning strike. The results have been validated using full threat lightning current tests.

  10. UWB Sampler for Wireless Communications and Radar

    National Research Council Canada - National Science Library

    Han, Jeongwoo; Nguyen, Cam

    2005-01-01

    An ultra wideband (UWB) sampler, realized using step recovery and Schottky diodes on coplanar waveguide, coplanar strips and slotlines, has been developed for UWB wireless communications and radar systems...

  11. VERTICAL ACTIVITY ESTIMATION USING 2D RADAR

    African Journals Online (AJOL)

    hennie

    estimates on aircraft vertical behaviour from a single 2D radar track. ... Fortunately, the problem of detecting relative vertical motion using a single 2D ..... awareness tools in scenarios where aerial activity sensing is typically limited to 2D.

  12. Radar Training Facility Local Area Network -

    Data.gov (United States)

    Department of Transportation — The RTF LAN system provides a progressive training environment for initial and refresher radar training qualification for new and re-hired FAA employees. Its purpose...

  13. Investigating nearby exoplanets via interstellar radar

    Science.gov (United States)

    Scheffer, Louis K.

    2014-01-01

    Interstellar radar is a potential intermediate step between passive observation of exoplanets and interstellar exploratory missions. Compared with passive observation, it has the traditional advantages of radar astronomy. It can measure surface characteristics, determine spin rates and axes, provide extremely accurate ranges, construct maps of planets, distinguish liquid from solid surfaces, find rings and moons, and penetrate clouds. It can do this even for planets close to the parent star. Compared with interstellar travel or probes, it also offers significant advantages. The technology required to build such a radar already exists, radar can return results within a human lifetime, and a single facility can investigate thousands of planetary systems. The cost, although too high for current implementation, is within the reach of Earth's economy.

  14. Snowballing and flying under the radar

    DEFF Research Database (Denmark)

    Pötz, Katharina Anna; Hjortsø, Carsten Nico Portefée

    2013-01-01

    management and venture development paths. More specifically, flying under radar in terms of operating under lower institutional requirements, and slowly accumulating resources (snowballing) are major leveraging strategies. We integrate our results into a hypothesized framework for resource management in East...

  15. Active Sensing Air Pressure Using Differential Absorption Barometric Radar

    Science.gov (United States)

    Lin, B.

    2016-12-01

    Tropical storms and other severe weathers cause huge life losses and property damages and have major impacts on public safety and national security. Their observations and predictions need to be significantly improved. This effort tries to develop a feasible active microwave approach that measures surface air pressure, especially over open seas, from space using a Differential-absorption BArometric Radar (DiBAR) operating at 50-55 GHz O2 absorption band in order to constrain assimilated dynamic fields of numerical weather Prediction (NWP) models close to actual conditions. Air pressure is the most important variable that drives atmospheric dynamics, and currently can only be measured by limited in-situ observations over oceans. Even over land there is no uniform coverage of surface air pressure measurements. Analyses show that with the proposed space radar the errors in instantaneous (averaged) pressure estimates can be as low as 4mb ( 1mb) under all weather conditions. NASA Langley research team has made substantial progresses in advancing the DiBAR concept. The feasibility assessment clearly shows the potential of surface barometry using existing radar technologies. The team has also developed a DiBAR system design, fabricated a Prototype-DiBAR (P-DiBAR) for proof-of-concept, conducted laboratory, ground and airborne P-DiBAR tests. The flight test results are consistent with the instrumentation goals. The precision and accuracy of radar surface pressure measurements are within the range of the theoretical analysis of the DiBAR concept. Observational system simulation experiments for space DiBAR performance based on the existing DiBAR technology and capability show substantial improvements in tropical storm predictions, not only for the hurricane track and position but also for the hurricane intensity. DiBAR measurements will provide us an unprecedented level of the prediction and knowledge on global extreme weather and climate conditions.

  16. Architecture for a 1-GHz Digital RADAR

    Science.gov (United States)

    Mallik, Udayan

    2011-01-01

    An architecture for a Direct RF-digitization Type Digital Mode RADAR was developed at GSFC in 2008. Two variations of a basic architecture were developed for use on RADAR imaging missions using aircraft and spacecraft. Both systems can operate with a pulse repetition rate up to 10 MHz with 8 received RF samples per pulse repetition interval, or at up to 19 kHz with 4K received RF samples per pulse repetition interval. The first design describes a computer architecture for a Continuous Mode RADAR transceiver with a real-time signal processing and display architecture. The architecture can operate at a high pulse repetition rate without interruption for an infinite amount of time. The second design describes a smaller and less costly burst mode RADAR that can transceive high pulse repetition rate RF signals without interruption for up to 37 seconds. The burst-mode RADAR was designed to operate on an off-line signal processing paradigm. The temporal distribution of RF samples acquired and reported to the RADAR processor remains uniform and free of distortion in both proposed architectures. The majority of the RADAR's electronics is implemented in digital CMOS (complementary metal oxide semiconductor), and analog circuits are restricted to signal amplification operations and analog to digital conversion. An implementation of the proposed systems will create a 1-GHz, Direct RF-digitization Type, L-Band Digital RADAR--the highest band achievable for Nyquist Rate, Direct RF-digitization Systems that do not implement an electronic IF downsample stage (after the receiver signal amplification stage), using commercially available off-the-shelf integrated circuits.

  17. Radar Location Equipment Development Program: Phase I

    Energy Technology Data Exchange (ETDEWEB)

    Sandness, G.A.; Davis, K.C.

    1985-06-01

    The work described in this report represents the first phase of a planned three-phase project designed to develop a radar system for monitoring waste canisters stored in a thick layer of bedded salt at the Waste Isolation Pilot Plant near Carlsbad, New Mexico. The canisters will be contained in holes drilled into the floor of the underground waste storage facility. It is hoped that these measurements can be made to accuracies of +-5 cm and +-2/sup 0/, respectively. The initial phase of this project was primarily a feasibility study. Its principal objective was to evaluate the potential effectiveness of the radar method in the planned canister monitoring application. Its scope included an investigation of the characteristics of radar signals backscattered from waste canisters, a test of preliminary data analysis methods, an assessment of the effects of salt and bentonite (a proposed backfill material) on the propagation of the radar signals, and a review of current ground-penetrating radar technology. A laboratory experiment was performed in which radar signals were backscattered from simulated waste canisters. The radar data were recorded by a digital data acquisition system and were subsequently analyzed by three different computer-based methods to extract estimates of canister location and tilt. Each of these methods yielded results that were accurate within a few centimeters in canister location and within 1/sup 0/ in canister tilt. Measurements were also made to determine the signal propagation velocities in salt and bentonite (actually a bentonite/sand mixture) and to estimate the signal attenuation rate in the bentonite. Finally, a product survey and a literature search were made to identify available ground-penetrating radar systems and alternative antenna designs that may be particularly suitable for this unique application. 10 refs., 21 figs., 4 tabs.

  18. Radar Location Equipment Development Program: Phase I

    International Nuclear Information System (INIS)

    Sandness, G.A.; Davis, K.C.

    1985-06-01

    The work described in this report represents the first phase of a planned three-phase project designed to develop a radar system for monitoring waste canisters stored in a thick layer of bedded salt at the Waste Isolation Pilot Plant near Carlsbad, New Mexico. The canisters will be contained in holes drilled into the floor of the underground waste storage facility. It is hoped that these measurements can be made to accuracies of +-5 cm and +-2 0 , respectively. The initial phase of this project was primarily a feasibility study. Its principal objective was to evaluate the potential effectiveness of the radar method in the planned canister monitoring application. Its scope included an investigation of the characteristics of radar signals backscattered from waste canisters, a test of preliminary data analysis methods, an assessment of the effects of salt and bentonite (a proposed backfill material) on the propagation of the radar signals, and a review of current ground-penetrating radar technology. A laboratory experiment was performed in which radar signals were backscattered from simulated waste canisters. The radar data were recorded by a digital data acquisition system and were subsequently analyzed by three different computer-based methods to extract estimates of canister location and tilt. Each of these methods yielded results that were accurate within a few centimeters in canister location and within 1 0 in canister tilt. Measurements were also made to determine the signal propagation velocities in salt and bentonite (actually a bentonite/sand mixture) and to estimate the signal attenuation rate in the bentonite. Finally, a product survey and a literature search were made to identify available ground-penetrating radar systems and alternative antenna designs that may be particularly suitable for this unique application. 10 refs., 21 figs., 4 tabs

  19. Single Bit Radar Systems for Digital Integration

    OpenAIRE

    Bjørndal, Øystein

    2017-01-01

    Small, low cost, radar systems have exciting applications in monitoring and imaging for the industrial, healthcare and Internet of Things (IoT) sectors. We here explore, and show the feasibility of, several single bit square wave radar architectures; that benefits from the continuous improvement in digital technologies for system-on-chip digital integration. By analysis, simulation and measurements we explore novel and harmonic-rich continuous wave (CW), stepped-frequency CW (SFCW) and freque...

  20. Development of a Software-Defined Radar

    Science.gov (United States)

    2017-10-01

    disrupt desired radar operation. The cognitive radar system discussed herein mitigates the effects of RFI by sensing and adapting the transmitted...present received data, and plot processed data. Top right: Calculates a “ flicker ” rate caused by an unknown issue where blank data are received due to...and plot processed data. Top right: Calculates a “ flicker ” rate caused by an unknown issue where blank data are received due to missed

  1. Improving ISR Radar Utilization (How I quit blaming the user and made the radar easier to use).

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter

    2014-08-01

    In modern multi - sensor multi - mode Intelligence, Surveillance, and Reconnaissance ( ISR ) platforms, the plethora of options available to a sensor/payload operator are quite large, leading to an over - worked operator often down - selecting to favorite sensors an d modes. For example, Full Motion Video (FMV) is justifiably a favorite sensor at the expense of radar modes, even if radar modes can offer unique and advantageous information. The challenge is then to increase the utilization of the radar modes in a man ner attractive to the sensor/payload operator. We propose that this is best accomplished by combining sensor modes and displays into 'super - modes'. - 4 - Acknowledgements This report is the result of a n unfunded research and development activity . Sandia Natio nal Laboratories is a multi - program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE - AC04 - 94AL850 00.

  2. Levee Health Monitoring With Radar Remote Sensing

    Science.gov (United States)

    Jones, C. E.; Bawden, G. W.; Deverel, S. J.; Dudas, J.; Hensley, S.; Yun, S.

    2012-12-01

    the entire network of more than 1100 miles of levees in the area, has used several sets of in situ data to validate the results. This type of levee health status information acquired with radar remote sensing could provide a cost-effective method to significantly improve the spatial and temporal coverage of levee systems and identify areas of concern for targeted levee maintenance, repair, and emergency response in the future. Our results show, for example, that during an emergency, when time is of the essence, SAR remote sensing offers the potential of rapidly providing levee status information that is effectively impossible to obtain over large areas using conventional monitoring, e.g., through high precision measurements of subcentimeter-scale levee movement prior to failure. The research described here was carried out in part at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

  3. Distress detection, location, and communications using advanced space technology. [satellite-borne synthetic aperture radar

    Science.gov (United States)

    Sivertson, W. E., Jr.

    1977-01-01

    This paper briefly introduces a concept for low-cost, global, day-night, all-weather disaster warning and assistance. Evolving, advanced space technology with passive radio frequency reflectors in conjunction with an imaging synthetic aperture radar is employed to detect, identify, locate, and provide passive communication with earth users in distress. This concept evolved from a broad NASA research on new global search and rescue techniques. Appropriate airborne radar test results from this research are reviewed and related to potential disaster applications. The analysis indicates the approach has promise for disaster communications relative to floods, droughts, earthquakes, volcanic eruptions, and severe storms.

  4. Raindrop size distribution and radar reflectivity-rain rate relationships for radar hydrology

    NARCIS (Netherlands)

    Uijlenhoet, R.

    2001-01-01

    The conversion of the radar reflectivity factor Z (mm6m-3) to rain rate R (mm h-1) is a crucial step in the hydrological application of weather radar measurements. It has been common practice for over 50 years now to take for this conversion a simple power law relationship between Z and R. It is the

  5. A 100 GHz Polarimetric Compact Radar Range for Scale-Model Radar Cross Section Measurements

    Science.gov (United States)

    2013-10-01

    common radar bands. ACKNOWLEDGEMENTS The authors wish to thank David Jillson (UML STL – Electrical Engineer) for efforts involved in RF and DC wiring...Waldman J., Fetterman H.R., Duffy P.E., Bryant T.G., Tannenwald P.E., “Submillimeter Model Measurements and Their Applications to Millimeter Radar

  6. Worldwide Weather Radar Imagery May Allow Substantial Increase in Meteorite Fall Recovery

    Science.gov (United States)

    Fries, Marc; Matson, Robert; Schaefer, Jacob; Fries, Jeffery; Hankey, Mike; Anderson, Lindsay

    2014-01-01

    Weather radar imagery is a valuable new technique for the rapid recovery of meteorite falls, to include falls which would not otherwise be recovered (e.g. Battle Mountain). Weather radar imagery reveals about one new meteorite fall per year (18 falls since 1998), using weather radars in the United States alone. However, an additional 75 other nations operate weather radar networks according to the UN World Meteorological Organization (WMO). If the imagery of those radars were analyzed, the current rate of meteorite falls could be improved considerably, to as much as 3.6 times the current recovery rate based on comparison of total radar areal coverage. Recently, the addition of weather radar imagery, seismometry and internet-based aggregation of eyewitness reports has improved the speed and accuracy of fresh meteorite fall recovery [e.g. 1,2]. This was demonstrated recently with the radar-enabled recovery of the Sutter's Mill fall [3]. Arguably, the meteorites recovered via these methods are of special scientific value as they are relatively unweathered, fresh falls. To illustrate this, a recent SAO/NASA ADS search using the keyword "meteorite" shows that all 50 of the top search results included at least one named meteorite recovered from a meteorite fall. This is true even though only 1260 named meteorite falls are recorded among the >49,000 individual falls recorded in the Meteoritical Society online database. The US NEXRAD system used thus far to locate meteorite falls covers most of the United States' surface area. Using a WMO map of the world's weather radars, we estimate that the total coverage of the other 75 national weather radar networks equals about 3.6x NEXRAD's coverage area. There are two findings to draw from this calculation: 1) For the past 16 years during which 18 falls are seen in US radar data, there should be an additional 65 meteorite falls recorded in worldwide radar imagery. Also: 2) if all of the world's radar data could be analyzed, the

  7. The contribution of the Georges Heights Experimental Radar Antenna to Australian radio astronomy

    Science.gov (United States)

    Orchiston, Wayne; Wendt, Harry

    2017-12-01

    During the late 1940s and throughout the1950s Australia was one of the world’s foremost astronomical nations owing primarily to the dynamic Radio Astronomy Group within the Commonwealth Scientific and Industrial Organisation’s Division of Radiophysics based in Sydney. The earliest celestial observations were made with former WWII radar antennas and simple Yagi aerials attached to recycled radar receivers, before more sophisticated purpose-built radio telescopes of various types were designed and developed. One of the recycled WWII antennas that was used extensively for pioneering radio astronomical research was an experimental radar antenna that initially was located at the Division’s short-lived Georges Heights Field Station but in 1948 was relocated to the new Potts Hill Field Station in suburban Sydney. In this paper we describe this unique antenna, and discuss the wide-ranging solar, galactic and extragalactic research programs that it was used for.

  8. 3D And 4D Cloud Lifecycle Investigations Using Innovative Scanning Radar Analysis Methods. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kollias, Pavlos [Stony Brook Univ., NY (United States)

    2017-04-23

    With the vast upgrades to the ARM program radar measurement capabilities in 2010 and beyond, our ability to probe the 3D structure of clouds and associated precipitation has increased dramatically. This project build on the PI's and co-I's expertisein the analysis of radar observations. The first research thrust aims to document the 3D morphological (as depicted by the radar reflectivity structure) and 3D dynamical (cloud$-$scale eddies) structure of boundary layer clouds. Unraveling the 3D dynamical structure of stratocumulus and shallow cumulus clouds requires decomposition of the environmental wind contribution and particle sedimentation velocity from the observed radial Doppler velocity. The second thrust proposes to unravel the mechanism of cumulus entrainment (location, scales) and its impact on microphysics utilizing radar measurements from the vertically pointing and new scanning radars at the ARM sites. The third research thrust requires the development of a cloud$-$tracking algorithm that monitors the properties of cloud.

  9. Value of a dual-polarized gap-filling radar in support of southern California post-fire debris-flow warnings

    Science.gov (United States)

    Jorgensen, David P.; Hanshaw, Maiana N.; Schmidt, Kevin M.; Laber, Jayme L; Staley, Dennis M.; Kean, Jason W.; Restrepo, Pedro J.

    2011-01-01

    A portable truck-mounted C-band Doppler weather radar was deployed to observe rainfall over the Station Fire burn area near Los Angeles, California, during the winter of 2009/10 to assist with debris-flow warning decisions. The deployments were a component of a joint NOAA–U.S. Geological Survey (USGS) research effort to improve definition of the rainfall conditions that trigger debris flows from steep topography within recent wildfire burn areas. A procedure was implemented to blend various dual-polarized estimators of precipitation (for radar observations taken below the freezing level) using threshold values for differential reflectivity and specific differential phase shift that improves the accuracy of the rainfall estimates over a specific burn area sited with terrestrial tipping-bucket rain gauges. The portable radar outperformed local Weather Surveillance Radar-1988 Doppler (WSR-88D) National Weather Service network radars in detecting rainfall capable of initiating post-fire runoff-generated debris flows. The network radars underestimated hourly precipitation totals by about 50%. Consistent with intensity–duration threshold curves determined from past debris-flow events in burned areas in Southern California, the portable radar-derived rainfall rates exceeded the empirical thresholds over a wider range of storm durations with a higher spatial resolution than local National Weather Service operational radars. Moreover, the truck-mounted C-band radar dual-polarimetric-derived estimates of rainfall intensity provided a better guide to the expected severity of debris-flow events, based on criteria derived from previous events using rain gauge data, than traditional radar-derived rainfall approaches using reflectivity–rainfall relationships for either the portable or operational network WSR-88D radars. Part of the reason for the improvement was due to siting the radar closer to the burn zone than the WSR-88Ds, but use of the dual-polarimetric variables

  10. Space Radar Image of Wenatchee, Washington

    Science.gov (United States)

    1994-01-01

    This spaceborne radar image shows a segment of the Columbia River as it passes through the area of Wenatchee, Washington, about 220 kilometers (136 miles) east of Seattle. The Wenatchee Mountains, part of the Cascade Range, are shown in green at the lower left of the image. The Cascades create a 'rain shadow' for the region, limiting rainfall east of the range to less than 26 centimeters (10 inches) per year. The radar's ability to see different types of vegetation is highlighted in the contrast between the pine forests, that appear in green and the dry valley plain that shows up as dark purple. The cities of Wenatchee and East Wenatchee are the grid-like areas straddling the Columbia River in the left center of the image. With a population of about 60,000, the region produces about half of Washington state's lucrative apple crop. Several orchard areas appear as green rectangular patches to the right of the river in the lower right center. Radar images such as these can be used to monitor land use patterns in areas such as Wenatchee, that have diverse and rapidly changing urban, agricultural and wild land pressures. This image was acquired by Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) onboard the space shuttle Endeavour on October 10, 1994. The image is 38 kilometers by 45 kilometers (24 miles by 30 miles) and is centered at 47.3 degrees North latitude, 120.1 degrees West longitude. North is toward the upper left. The colors are assigned to different radar frequencies and polarizations of the radar as follows: red is L-band, horizontally transmitted and received; green is L-band, horizontally transmitted, vertically received; and blue is C-band, horizontally transmitted, vertically received. SIR-C/X-SAR, a joint mission of the German, Italian, and United States space agencies, is part of NASA's Mission to Planet Earth.

  11. Sea clutter scattering, the K distribution and radar performance

    CERN Document Server

    Ward, Keith; Watts, Simon

    2013-01-01

    Sea Clutter: Scattering, the K Distribution and Radar Performance, 2nd Edition gives an authoritative account of our current understanding of radar sea clutter. Topics covered include the characteristics of radar sea clutter, modelling radar scattering by the ocean surface, statistical models of sea clutter, the simulation of clutter and other random processes, detection of small targets in sea clutter, imaging ocean surface features, radar detection performance calculations, CFAR detection, and the specification and measurement of radar performance. The calculation of the performance of pract

  12. Radar principles for the nonspecialist, 3rd edition

    CERN Document Server

    Toomay, John

    2004-01-01

    Radar Principles for the Non-specialist, Third Edition continues its popular tradition: to distill the very complex technology of radar into its fundamentals, tying them to the laws of nature on one end and to the most modern and complex systems on the other. It starts with electromagnetic propagation, describes a radar of the utmost simplicity, and derives the radar range equation from that simple radar. Once the range equation is available, the book attacks the meaning of each term in it, moving through antennas, detection and tracking, radar cross-section, waveforms andsignal proces

  13. Using the VAHIRR Radar Algorithm to Investigate Lightning Cessation

    Science.gov (United States)

    Stano, Geoffrey T.; Schultz, Elise V.; Petersen, Walter A.

    2012-01-01

    Accurately determining the threat posed by lightning is a major area for improved operational forecasts. Most efforts have focused on the initiation of lightning within a storm, with far less effort spent investigating lightning cessation. Understanding both components, initiation and cessation, are vital to improving lightning safety. Few organizations actively forecast lightning onset or cessation. One such organization is the 45th Weather Squadron (45WS) for the Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS). The 45WS has identified that charged anvil clouds remain a major threat of continued lightning and can greatly extend the window of a potential lightning strike. Furthermore, no discernable trend of total lightning activity has been observed consistently for all storms. This highlights the need for more research to find a robust method of knowing when a storm will cease producing lightning. Previous lightning cessation work has primarily focused on forecasting the cessation of cloud-to -ground lightning only. A more recent, statistical study involved total lightning (both cloud-to-ground and intracloud). Each of these previous works has helped the 45WS take steps forward in creating improved and ultimately safer lightning cessation forecasts. Each study has either relied on radar data or recommended increased use of radar data to improve cessation forecasts. The reasoning is that radar data is able to either directly or by proxy infer more about dynamical environment leading to cloud electrification and eventually lightning cessation. The authors of this project are focusing on a two ]step approach to better incorporate radar data and total lightning to improve cessation forecasts. This project will utilize the Volume Averaged Height Integrated Radar Reflectivity (VAHIRR) algorithm originally developed during the Airborne Field Mill II (ABFM II) research project. During the project, the VAHIRR product showed a trend of increasing

  14. Three-dimensional, subsurface imaging synthetic aperture radar

    International Nuclear Information System (INIS)

    Moussally, G.J.

    1994-01-01

    The objective of this applied research and devolpment project is to develop a system known as 3-D SISAR. This sytem consists of a gound penetrating radar with software algorithms designed for detection, location, and identification of buried objects in the underground hazardous waste environments found at US DOE storage sites. Three-dimensional maps can assist the development of remdiation strategies and characterization of the digface during remediation. The system should also be useful for monitoring hydrocarbon-based contaminant migration after remediation. 5 figs

  15. Advanced radar detection schemes under mismatched signal models

    CERN Document Server

    Bandiera, Francesco

    2009-01-01

    Adaptive detection of signals embedded in correlated Gaussian noise has been an active field of research in the last decades. This topic is important in many areas of signal processing such as, just to give some examples, radar, sonar, communications, and hyperspectral imaging. Most of the existing adaptive algorithms have been designed following the lead of the derivation of Kelly's detector which assumes perfect knowledge of the target steering vector. However, in realistic scenarios, mismatches are likely to occur due to both environmental and instrumental factors. When a mismatched signal

  16. Signal compression in radar using FPGA

    Directory of Open Access Journals (Sweden)

    Enrique Escamilla Hemández

    2010-01-01

    Full Text Available El presente artículo muestra la puesta en práctica de hardware para realizar el procesamiento en tiempo real de la señal de radar usando una técnica simple, rápida basada en arquitectura de FPGA (Field Programmable Gate Array. El proceso incluye diversos procedimientos de enventanado durante la compresión del pulso del radar de apertura sintética (SAR. El proceso de compresión de la señal de radar se hace con un filtro acoplado. que aplica funciones clásicas y nuevas de enventanado, donde nos centramos en obtener una mejor atenuación para los valores de lóbulos laterales. La arquitectura propuesta explota los recursos de computación paralela de los dispositivos FPGA para alcanzar una mejor velocidad de cómputo. Las investigaciones experimentales han demostrado que los mejores resultados para el funcionamiento de la compresión del pulso se han obtenido usando las funciones atómicas, mejorando el funcionamiento del sistema del radar en presencia de ruido, y consiguiendo una pequeña degradación en la resolución de rango. La puesta en práctica del tratamiento de señales en el sistema de radar en tiempo real se discute y se justifica la eficiencia de la arquitectura de hardware propuesta.

  17. Developments in target micro-Doppler signatures analysis: radar imaging, ultrasound and through-the-wall radar

    OpenAIRE

    Clemente, C.; Balleri, A.; Woodbridge, K.; Soraghan, J. J.

    2013-01-01

    Target motions, other than the main bulk translation of the target, induce Doppler modulations around the main Doppler shift that form what is commonly called a target micro-Doppler signature. Radar micro-Doppler signatures are generally both target and action speci c and hence can be used to classify and recognise targets as well as to identify possible threats. In recent years, research into the use of micro-Doppler signatures for target classi cation to address many defence and security ch...

  18. Manajemen Redaksional Pada Surat Kabar Harian Umum Radar Cirebon (Studi Deskriptif Kualitatif Manajemen Redaksional pada Surat Kabar Harian Umum Radar Cirebon Periode Januari-Mei 2013

    Directory of Open Access Journals (Sweden)

    M Irfan Fazryansyah

    2014-01-01

    Full Text Available Mass media after the era of reform becomes the mass communication facility and instrument shaper of public opinion , it is helping in human life to exchanging ideas, sharing of experience and information in the volume of a relatively large. This research aims to understand planning, organizing, mobilizing and supervision in the management of editorial on daily newspaper of Radar Cirebon. A method of this research is descriptive qualitative, data was gathered by direct interview, observasion and availability of literature studies. Based on covered can be drawn conclusions that ( 1 In the planning stages, daily newspaper of Radar Cirebon well to plan, it is seen from the success of meeting and a meeting of the editor. ( 2 the organizing stages, the editor management has forming the organization structure and their duty to each personel.( 3 The mobilization phase is very important to editor management in daily newspaper of Radar Cirebon, because of mobilizarion, the management of material goes well, start from the reporting process, writing, editing till becoming the news. (4 In the phase supervision in editorial management of daily newspaper of Radar Cirebon conducted in the form of direct briefing to reporters during a news manuscript edited by the editor still experiencing a shortage of data.

  19. Broadband Counter-Wound Spiral Antenna for Subsurface Radar Applications

    National Research Council Canada - National Science Library

    Yong, Lim

    2003-01-01

    Subsurface radar also known as ground-penetrating radar is increasingly being used for the detection and location of buried objects such as mines and structure that are found within the upper regions...

  20. Operational Bright-Band Snow Level Detection Using Doppler Radar

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A method to detect the bright-band snow level from radar reflectivity and Doppler vertical velocity data collection with an atmospheric profiling Doppler radar. The...

  1. Autonomous Non-Linear Classification of LPI Radar Signal Modulations

    National Research Council Canada - National Science Library

    Gulum, Taylan O

    2007-01-01

    ...) radar modulations is investigated. A software engineering architecture that allows a full investigation of various preprocessing algorithms and classification techniques is applied to a database of important LPI radar waveform...

  2. Distributed Subarray Antennas for Multifunction Phased-Array Radar

    National Research Council Canada - National Science Library

    Lin, Chih-heng

    2003-01-01

    As the target radar cross section (RCS) continuously decreases, the need for high-resolution high-gain radar increases, One approach to high resolution is to use distributed subarray antennas (DSAs...

  3. GPM GROUND VALIDATION PAWNEE RADAR MC3E V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The Pawnee radar data for the Midlatitude Continental Convective Clouds Experiment (MC3E) held in Oklahoma were collected on May 24, 2011 to support the CHILL radar...

  4. NOAA Next Generation Radar (NEXRAD) Level 2 Base Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset consists of Level II weather radar data collected from Next-Generation Radar (NEXRAD) stations located in the contiguous United States, Alaska, Hawaii,...

  5. Ships as salient objects in synthetic aperture radar imaginary

    CSIR Research Space (South Africa)

    Schwegmann, Colin P

    2016-07-01

    Full Text Available The widespread access to Synthetic Aperture Radar data has created a need for more precise ship extraction, specifically in low-to-medium resolution imagery. While Synthetic Aperture Radar pixel resolution is improving for a large swaths...

  6. Stepped-frequency radar sensors theory, analysis and design

    CERN Document Server

    Nguyen, Cam

    2016-01-01

    This book presents the theory, analysis and design of microwave stepped-frequency radar sensors. Stepped-frequency radar sensors are attractive for various sensing applications that require fine resolution. The book consists of five chapters. The first chapter describes the fundamentals of radar sensors including applications followed by a review of ultra-wideband pulsed, frequency-modulated continuous-wave (FMCW), and stepped-frequency radar sensors. The second chapter discusses a general analysis of radar sensors including wave propagation in media and scattering on targets, as well as the radar equation. The third chapter addresses the analysis of stepped-frequency radar sensors including their principles and design parameters. Chapter 4 presents the development of two stepped-frequency radar sensors at microwave and millimeter-wave frequencies based on microwave integrated circuits (MICs), microwave monolithic integrated circuits (MMICs) and printed-circuit antennas, and discusses their signal processing....

  7. Stellwagen Bank National Marine Sanctuary - Synthetic Aperture Radar (SAR) Imagery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This geodatabase contains Synthetic Aperture Radar images (SAR), which consist of a fine resolution (12.5-50m), two-dimensional radar backscatter map of the...

  8. Challenges in X-band Weather Radar Data Calibration

    DEFF Research Database (Denmark)

    Thorndahl, Søren; Rasmussen, Michael R.

    2009-01-01

    Application of weather radar data in urban hydrology is evolving and radar data is now applied for both modelling, analysis and real time control purposes. In these contexts, it is all-important that the radar data well calibrated and adjusted in order to obtain valid quantitative precipitation e...... estimates. This paper compares two calibration procedures for a small marine X-band radar by comparing radar data with rain gauge data. Validation shows a very good consensus with regards to precipitation volumes, but more diverse results on peak rain intensities.......Application of weather radar data in urban hydrology is evolving and radar data is now applied for both modelling, analysis and real time control purposes. In these contexts, it is all-important that the radar data well calibrated and adjusted in order to obtain valid quantitative precipitation...

  9. NOAA Next Generation Radar (NEXRAD) Level 3 Products

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset consists of Level 3 weather radar products collected from Next-Generation Radar (NEXRAD) stations located in the contiguous United States, Alaska,...

  10. Venus radar mapper attitude reference quaternion

    Science.gov (United States)

    Lyons, D. T.

    1986-01-01

    Polynomial functions of time are used to specify the components of the quaternion which represents the nominal attitude of the Venus Radar mapper spacecraft during mapping. The following constraints must be satisfied in order to obtain acceptable synthetic array radar data: the nominal attitude function must have a large dynamic range, the sensor orientation must be known very accurately, the attitude reference function must use as little memory as possible, and the spacecraft must operate autonomously. Fitting polynomials to the components of the desired quaternion function is a straightforward method for providing a very dynamic nominal attitude using a minimum amount of on-board computer resources. Although the attitude from the polynomials may not be exactly the one requested by the radar designers, the polynomial coefficients are known, so they do not contribute to the attitude uncertainty. Frequent coefficient updates are not required, so the spacecraft can operate autonomously.

  11. Radar cross section measurements using terahertz waves

    DEFF Research Database (Denmark)

    Iwaszczuk, Krzysztof; Heiselberg, Henning; Jepsen, Peter Uhd

    2010-01-01

    Radar cross sections at terahertz frequencies are measured on scale models of aircrafts. A time domain broadband THz system generates freely propagating THz pulses measured with sub-picosecond time resolution. The THz radiation is generated using fs laser pulses by optical rectification...... in order to measure realistic radar cross sections. RCS polar and azimuthal angle plots of F-16 and F-35 are presented....... in a lithium niobate crystal with application of the tilted wave front method, resulting in high electric field THz pulses with a broad band spectrum from 100 GHz up to 4 THz. The corresponding wave lengths are two orders of magnitude smaller than normal radars and we therefore use scale models of size 5-10 cm...

  12. Plasma-based radar cross section reduction

    CERN Document Server

    Singh, Hema; Jha, Rakesh Mohan

    2016-01-01

    This book presents a comprehensive review of plasma-based stealth, covering the basics, methods, parametric analysis, and challenges towards the realization of the idea. The concealment of aircraft from radar sources, or stealth, is achieved through shaping, radar absorbing coatings, engineered materials, or plasma, etc. Plasma-based stealth is a radar cross section (RCS) reduction technique associated with the reflection and absorption of incident electromagnetic (EM) waves by the plasma layer surrounding the structure. A plasma cloud covering the aircraft may give rise to other signatures such as thermal, acoustic, infrared, or visual. Thus it is a matter of concern that the RCS reduction by plasma enhances its detectability due to other signatures. This needs a careful approach towards the plasma generation and its EM wave interaction. The book starts with the basics of EM wave interactions with plasma, briefly discuss the methods used to analyze the propagation characteristics of plasma, and its generatio...

  13. Comments on airborne ISR radar utilization

    Science.gov (United States)

    Doerry, A. W.

    2016-05-01

    A sensor/payload operator for modern multi-sensor multi-mode Intelligence, Surveillance, and Reconnaissance (ISR) platforms is often confronted with a plethora of options in sensors and sensor modes. This often leads an over-worked operator to down-select to favorite sensors and modes; for example a justifiably favorite Full Motion Video (FMV) sensor at the expense of radar modes, even if radar modes can offer unique and advantageous information. At best, sensors might be used in a serial monogamous fashion with some cross-cueing. The challenge is then to increase the utilization of the radar modes in a manner attractive to the sensor/payload operator. We propose that this is best accomplished by combining sensor modes and displays into `super-modes'.

  14. SKB - PNC. Development of tunnel radar antennas

    International Nuclear Information System (INIS)

    Falk, L.

    1991-07-01

    Tunnel antennas for the RAMAC borehole radar system have been developed and tested in the field. The antennas are of the loaded dipole type and the receiver and transmitter electronics have been rebuilt to screen them from the antennas. A series of measurements has demonstrated that the radar pulse is short and well shaped and relatively free from ringing, even compared with the existing borehole antennas. Two antenna sets were tested: one centered at 60 MHz and another above 100 MHz. Both produced excellent radar pictures when tested in tunnels in Stripa mine. The antennas have been designed to be easy to carry, since the signal quality often depends on the way the antenna is held relative to electric conductors in the tunnels. (au) (46 figs., 57 refs.)

  15. Smoothing Motion Estimates for Radar Motion Compensation.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-07-01

    Simple motion models for complex motion environments are often not adequate for keeping radar data coherent. Eve n perfect motion samples appli ed to imperfect models may lead to interim calculations e xhibiting errors that lead to degraded processing results. Herein we discuss a specific i ssue involving calculating motion for groups of pulses, with measurements only available at pulse-group boundaries. - 4 - Acknowledgements This report was funded by General A tomics Aeronautical Systems, Inc. (GA-ASI) Mission Systems under Cooperative Re search and Development Agre ement (CRADA) SC08/01749 between Sandia National Laboratories and GA-ASI. General Atomics Aeronautical Systems, Inc. (GA-ASI), an affilia te of privately-held General Atomics, is a leading manufacturer of Remotely Piloted Aircraft (RPA) systems, radars, and electro-optic and rel ated mission systems, includin g the Predator(r)/Gray Eagle(r)-series and Lynx(r) Multi-mode Radar.

  16. Analysis on Target Detection and Classification in LTE Based Passive Forward Scattering Radar

    Directory of Open Access Journals (Sweden)

    Raja Syamsul Azmir Raja Abdullah

    2016-09-01

    Full Text Available The passive bistatic radar (PBR system can utilize the illuminator of opportunity to enhance radar capability. By utilizing the forward scattering technique and procedure into the specific mode of PBR can provide an improvement in target detection and classification. The system is known as passive Forward Scattering Radar (FSR. The passive FSR system can exploit the peculiar advantage of the enhancement in forward scatter radar cross section (FSRCS for target detection. Thus, the aim of this paper is to show the feasibility of passive FSR for moving target detection and classification by experimental analysis and results. The signal source is coming from the latest technology of 4G Long-Term Evolution (LTE base station. A detailed explanation on the passive FSR receiver circuit, the detection scheme and the classification algorithm are given. In addition, the proposed passive FSR circuit employs the self-mixing technique at the receiver; hence the synchronization signal from the transmitter is not required. The experimental results confirm the passive FSR system’s capability for ground target detection and classification. Furthermore, this paper illustrates the first classification result in the passive FSR system. The great potential in the passive FSR system provides a new research area in passive radar that can be used for diverse remote monitoring applications.

  17. Analysis on Target Detection and Classification in LTE Based Passive Forward Scattering Radar.

    Science.gov (United States)

    Raja Abdullah, Raja Syamsul Azmir; Abdul Aziz, Noor Hafizah; Abdul Rashid, Nur Emileen; Ahmad Salah, Asem; Hashim, Fazirulhisyam

    2016-09-29

    The passive bistatic radar (PBR) system can utilize the illuminator of opportunity to enhance radar capability. By utilizing the forward scattering technique and procedure into the specific mode of PBR can provide an improvement in target detection and classification. The system is known as passive Forward Scattering Radar (FSR). The passive FSR system can exploit the peculiar advantage of the enhancement in forward scatter radar cross section (FSRCS) for target detection. Thus, the aim of this paper is to show the feasibility of passive FSR for moving target detection and classification by experimental analysis and results. The signal source is coming from the latest technology of 4G Long-Term Evolution (LTE) base station. A detailed explanation on the passive FSR receiver circuit, the detection scheme and the classification algorithm are given. In addition, the proposed passive FSR circuit employs the self-mixing technique at the receiver; hence the synchronization signal from the transmitter is not required. The experimental results confirm the passive FSR system's capability for ground target detection and classification. Furthermore, this paper illustrates the first classification result in the passive FSR system. The great potential in the passive FSR system provides a new research area in passive radar that can be used for diverse remote monitoring applications.

  18. Assessment of human respiration patterns via noncontact sensing using Doppler multi-radar system.

    Science.gov (United States)

    Gu, Changzhan; Li, Changzhi

    2015-03-16

    Human respiratory patterns at chest and abdomen are associated with both physical and emotional states. Accurate measurement of the respiratory patterns provides an approach to assess and analyze the physical and emotional states of the subject persons. Not many research efforts have been made to wirelessly assess different respiration patterns, largely due to the inaccuracy of the conventional continuous-wave radar sensor to track the original signal pattern of slow respiratory movements. This paper presents the accurate assessment of different respiratory patterns based on noncontact Doppler radar sensing. This paper evaluates the feasibility of accurately monitoring different human respiration patterns via noncontact radar sensing. A 2.4 GHz DC coupled multi-radar system was used for accurate measurement of the complete respiration patterns without any signal distortion. Experiments were carried out in the lab environment to measure the different respiration patterns when the subject person performed natural breathing, chest breathing and diaphragmatic breathing. The experimental results showed that accurate assessment of different respiration patterns is feasible using the proposed noncontact radar sensing technique.

  19. Doppler HF Radar Application for the Study of Spatial Structure of Currents in the Black Sea

    Directory of Open Access Journals (Sweden)

    V.V. Gorbatskiy

    2017-06-01

    Full Text Available The results of the surface current spatial structure observations performed by SeaSonde Doppler HF radar (operating frequency is 25 MHz in the Black Sea region adjacent to the city of Gelendzhik are represented. The observations imply a special technique consisting in successive measurements at two selected points of the coastline. Initially, the measurements are carried out in the first of two selected coastal points during two hours. Then the radar system is transferred to the second point on the coast where the procedure is repeated. At that the velocity field is assumed to remain unchanged during the total measurement period (including the time of the radar displacement from both points. The measurement results are shown in a form of a spatial map of the current velocity vectors in the research region (with 20 × 20 km dimensions. Some features of the current spatial and temporal variability in the coastal waters are revealed. Particularly, the eddy-like formations (the diameter is a few kilometers which rapidly move and collapse. Since similar eddies are detected using the contact measurement methods, complex and variable structure of the surface currents measured by a radar does not seem to be an artifact. Nevertheless, reliability of the data resulted from the radar measurements of the surface current velocity field should be verified in future by comparing it with the results of the quasi-synchronous velocity field measurements performed by stationary, drifting and towed velocity meters.

  20. Space Radar Image of Central Sumatra, Indonesia

    Science.gov (United States)

    1994-01-01

    This is a radar image of the central part of the island of Sumatra in Indonesia that shows how the tropical rainforest typical of this country is being impacted by human activity. Native forest appears in green in this image, while prominent pink areas represent places where the native forest has been cleared. The large rectangular areas have been cleared for palm oil plantations. The bright pink zones are areas that have been cleared since 1989, while the dark pink zones are areas that were cleared before 1989. These radar data were processed as part of an effort to assist oil and gas companies working in the area to assess the environmental impact of both their drilling operations and the activities of the local population. Radar images are useful in these areas because heavy cloud cover and the persistent smoke and haze associated with deforestation have prevented usable visible-light imagery from being acquired since 1989. The dark shapes in the upper right (northeast) corner of the image are a chain of lakes in flat coastal marshes. This image was acquired in October 1994 by the Spaceborne Imaging Radar C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) onboard the space shuttle Endeavour. Environmental changes can be easily documented by comparing this image with visible-light data that were acquired in previous years by the Landsat satellite. The image is centered at 0.9 degrees north latitude and 101.3 degrees east longitude. The area shown is 50 kilometers by 100 kilometers (31 miles by 62 miles). The colors in the image are assigned to different frequencies and polarizations of the radar as follows: red is L-band horizontally transmitted, horizontally received; green is L-band horizontally transmitted, vertically received; blue is L-band vertically transmitted, vertically received. SIR-C/X-SAR, a joint mission of the German, Italian and United States space agencies, is part of NASA's Mission to Planet Earth program.

  1. Quantitative precipitation estimation in complex orography using quasi-vertical profiles of dual polarization radar variables

    Science.gov (United States)

    Montopoli, Mario; Roberto, Nicoletta; Adirosi, Elisa; Gorgucci, Eugenio; Baldini, Luca

    2017-04-01

    . To avoid facing such a complexity, especially with a view to operational implementation, we propose to look at the features of the vertical profile of rain (VPR), i.e. after performing the rain estimation. This procedure allows characterizing a single variable (i.e. rain) when dealing with vertical extrapolations. Some case studies of severe thunderstorms that hit the mountainous area surrounding Rome in Italy causing floodings and damages and observed by the research C-band polarization agility Doppler radar named Polar 55C, managed by the Institute of Atmospheric Sciences and Climate (ISAC) at the National Research Council of Italy (CNR), are used to support the concept of VPR. Our results indicate that the combined algorithm, which merges together the differential phase shift (Kdp), the reflectivity factor at horizontal polarization (Zhh), and differential reflectivity (Zdr), once accurately processed, performs best among those tested that make use of Zhh alone, Kdp alone, and Zhh and Zdr pair. Improvements from 25% to 80% are found for the total rain accumulations in terms of normalized bias when the VPR extrapolation is applied.

  2. Monitoring of rain water storage in forests with satellite radar

    OpenAIRE

    de Jong, JJM; Klaassen, W; Kuiper, PJC

    2002-01-01

    The sensitivity of radar backscatter to the amount of intercepted rain in temperate deciduous forests is analyzed to determine the feasibility of retrieval of this parameter from satellite radar data. A backscatter model is validated with X-band radar measurements of a single tree exposed to rain. A good agreement between simulation and measurements is observed and this demonstrates the ability of radar to measure the amount of intercepted rain. The backscatter model is next applied to simula...

  3. Digital data acquisition for laser radar for vibration analysis

    OpenAIRE

    Montes, Felix G.

    1998-01-01

    Approved for public release; distribution is unlimited Laser radar for vibration analysis represents a military application to develop a target identification system in the future. The problem addressed is how to analyze the vibrations of a target illuminated by the laser radar to achieve a positive identification. This thesis develops a computer-based data acquisition and analysis system for improving the laser radar capability. Specifically, a review is made of the CO2 laser radar, coher...

  4. Runoff Calculation by Neural Networks Using Radar Rainfall Data

    OpenAIRE

    岡田, 晋作; 四俵, 正俊

    1997-01-01

    Neural networks, are used to calculate runoff from weather radar data and ground rain gauge data. Compared to usual runoff models, it is easier to use radar data in neural network runoff calculation. Basically you can use the radar data directly, or without transforming them into rainfall, as the input of the neural network. A situation with the difficulty of ground measurement is supposed. To cover the area lacking ground rain gauge, radar data are used. In case that the distribution of grou...

  5. The Status of the ACRF Millimeter Wave Cloud Radars (MMCRs), the Path Forward for Future MMCR Upgrades, the Concept of 3D Volume Imaging Radar and the UAV Radar

    Energy Technology Data Exchange (ETDEWEB)

    P Kollias; MA Miller; KB Widener; RT Marchand; TP Ackerman

    2005-12-30

    The United States (U.S.) Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) operates millimeter wavelength cloud radars (MMCRs) in several climatological regimes. The MMCRs, are the primary observing tool for quantifying the properties of nearly all radiatively important clouds over the ACRF sites. The first MMCR was installed at the ACRF Southern Great Plains (SGP) site nine years ago and its original design can be traced to the early 90s. Since then, several MMCRs have been deployed at the ACRF sites, while no significant hardware upgrades have been performed. Recently, a two-stage upgrade (first C-40 Digital Signal Processors [DSP]-based, and later the PC-Integrated Radar AcQuisition System [PIRAQ-III] digital receiver) of the MMCR signal-processing units was completed. Our future MMCR related goals are: 1) to have a cloud radar system that continues to have high reliability and uptime and 2) to suggest potential improvements that will address increased sensitivity needs, superior sampling and low cost maintenance of the MMCRs. The Traveling Wave Tube (TWT) technology, the frequency (35-GHz), the radio frequency (RF) layout, antenna, the calibration and radar control procedure and the environmental enclosure of the MMCR remain assets for our ability to detect the profile of hydrometeors at all heights in the troposphere at the ACRF sites.

  6. The ISMAR high frequency coastal radar network: Monitoring surface currents for management of marine resources

    DEFF Research Database (Denmark)

    Carlson, Daniel Frazier

    2015-01-01

    The Institute of Marine Sciences (ISMAR) of the National Research Council of Italy (CNR) established a High Frequency (HF) Coastal Radar Network for the measurement of the velocity of surface currents in coastal seas. The network consists of four HF radar systems located on the coast of the Gargano...... Promontory (Southern Adriatic, Italy). The network has been operational since May 2013 and covers an area of approximately 1700 square kilometers in the Gulf of Manfredonia. Quality Assessment (QA) procedures are applied for the systems deployment and maintenance and Quality Control (QC) procedures...

  7. Optimization of Soil Hydraulic Model Parameters Using Synthetic Aperture Radar Data: An Integrated Multidisciplinary Approach

    DEFF Research Database (Denmark)

    Pauwels, Valentijn; Balenzano, Anna; Satalino, Giuseppe

    2009-01-01

    It is widely recognized that Synthetic Aperture Radar (SAR) data are a very valuable source of information for the modeling of the interactions between the land surface and the atmosphere. During the last couple of decades, most of the research on the use of SAR data in hydrologic applications has...... that no direct relationships between the remote-sensing observations, more specifically radar backscatter values, and the parameter values can be derived. However, land surface models can provide these relationships. The objective of this paper is to retrieve a number of soil physical model parameters through...

  8. Comparison of classification algorithms for various methods of preprocessing radar images of the MSTAR base

    Science.gov (United States)

    Borodinov, A. A.; Myasnikov, V. V.

    2018-04-01

    The present work is devoted to comparing the accuracy of the known qualification algorithms in the task of recognizing local objects on radar images for various image preprocessing methods. Preprocessing involves speckle noise filtering and normalization of the object orientation in the image by the method of image moments and by a method based on the Hough transform. In comparison, the following classification algorithms are used: Decision tree; Support vector machine, AdaBoost, Random forest. The principal component analysis is used to reduce the dimension. The research is carried out on the objects from the base of radar images MSTAR. The paper presents the results of the conducted studies.

  9. Space Radar Image of Maui, Hawaii

    Science.gov (United States)

    1994-01-01

    This spaceborne radar image shows the 'Valley Island' of Maui, Hawaii. The cloud-penetrating capabilities of radar provide a rare view of many parts of the island, since the higher elevations are frequently shrouded in clouds. The light blue and yellow areas in the lowlands near the center are sugar cane fields. The three major population centers, Lahaina on the left at the western tip of island, Wailuku left of center, and Kihei in the lower center appear as small yellow, white or purple mottled areas. West Maui volcano, in the lower left, is 1800 meters high (5900 feet) and is considered extinct. The entire eastern half of the island consists of East Maui volcano, which rises to an elevation of 3200 meters (10,500 feet) and features a spectacular crater called Haleakala at its summit. Haleakala Crater was produced by erosion during previous ice ages rather than by volcanic activity, although relatively recent small eruptions have produced the numerous volcanic cones and lava flows that can be seen on the floor of the crater. The most recent eruption took place near the coast at the southwestern end of East Maui volcano in the late 1700s. Such a time frame indicates that East Maui should be considered a dormant, rather than an extinct volcano. A new eruption is therefore possible in the next few hundred years. The multi-wavelength capability of the SIR-C radar also permits differences in the vegetation cover on the middle flanks of East Maui to be identified. Rain forests appear in yellow, while grassland is shown in dark green, pink and blue. Radar images such as this one are being used by scientists to understand volcanic processes and to assess potential threats that future activity may pose to local populations. This image was acquired by Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) onboard the space shuttle Endeavour on April 16, 1994. The image is 73.7 kilometers by 48.7 kilometers (45.7 miles by 30.2 miles) and is centered at 20

  10. Multi-antenna synthetic aperture radar

    CERN Document Server

    Wang, Wen-Qin

    2013-01-01

    Synthetic aperture radar (SAR) is a well-known remote sensing technique, but conventional single-antenna SAR is inherently limited by the minimum antenna area constraint. Although there are still technical issues to overcome, multi-antenna SAR offers many benefits, from improved system gain to increased degrees-of-freedom and system flexibility. Multi-Antenna Synthetic Aperture Radar explores the potential and challenges of using multi-antenna SAR in microwave remote sensing applications. These applications include high-resolution imaging, wide-swath remote sensing, ground moving target indica

  11. Radar fall detection using principal component analysis

    Science.gov (United States)

    Jokanovic, Branka; Amin, Moeness; Ahmad, Fauzia; Boashash, Boualem

    2016-05-01

    Falls are a major cause of fatal and nonfatal injuries in people aged 65 years and older. Radar has the potential to become one of the leading technologies for fall detection, thereby enabling the elderly to live independently. Existing techniques for fall detection using radar are based on manual feature extraction and require significant parameter tuning in order to provide successful detections. In this paper, we employ principal component analysis for fall detection, wherein eigen images of observed motions are employed for classification. Using real data, we demonstrate that the PCA based technique provides performance improvement over the conventional feature extraction methods.

  12. Relating multifrequency radar backscattering to forest biomass: Modeling and AIRSAR measurement

    Science.gov (United States)

    Sun, Guo-Qing; Ranson, K. Jon

    1992-01-01

    During the last several years, significant efforts in microwave remote sensing were devoted to relating forest parameters to radar backscattering coefficients. These and other studies showed that in most cases, the longer wavelength (i.e. P band) and cross-polarization (HV) backscattering had higher sensitivity and better correlation to forest biomass. This research examines this relationship in a northern forest area through both backscatter modeling and synthetic aperture radar (SAR) data analysis. The field measurements were used to estimate stand biomass from forest weight tables. The backscatter model described by Sun et al. was modified to simulate the backscattering coefficients with respect to stand biomass. The average number of trees per square meter or radar resolution cell, and the average tree height or diameter breast height (dbh) in the forest stand are the driving parameters of the model. The rest of the soil surface, orientation, and size distributions of leaves and branches, remain unchanged in the simulations.

  13. High-resolution imaging using a wideband MIMO radar system with two distributed arrays.

    Science.gov (United States)

    Wang, Dang-wei; Ma, Xiao-yan; Chen, A-Lei; Su, Yi

    2010-05-01

    Imaging a fast maneuvering target has been an active research area in past decades. Usually, an array antenna with multiple elements is implemented to avoid the motion compensations involved in the inverse synthetic aperture radar (ISAR) imaging. Nevertheless, there is a price dilemma due to the high level of hardware complexity compared to complex algorithm implemented in the ISAR imaging system with only one antenna. In this paper, a wideband multiple-input multiple-output (MIMO) radar system with two distributed arrays is proposed to reduce the hardware complexity of the system. Furthermore, the system model, the equivalent array production method and the imaging procedure are presented. As compared with the classical real aperture radar (RAR) imaging system, there is a very important contribution in our method that the lower hardware complexity can be involved in the imaging system since many additive virtual array elements can be obtained. Numerical simulations are provided for testing our system and imaging method.

  14. Bubbles in Titan’s Seas: Nucleation, Growth, and RADAR Signature

    Science.gov (United States)

    Cordier, Daniel; Liger-Belair, Gérard

    2018-05-01

    In the polar regions of Titan, the main satellite of Saturn, hydrocarbon seas have been discovered by the Cassini–Huygens mission. RADAR observations have revealed surprising and transient bright areas over the Ligeia Mare surface. As suggested by recent research, bubbles could explain these strange features. However, the nucleation and growth of such bubbles, together with their RADAR reflectivity, have never been investigated. All of these aspects are critical to an actual observation. We have thus applied the classical nucleation theory to our context, and we developed a specific radiative transfer model that is appropriate for bubble streams in cryogenic liquids. According to our results, the sea bed appears to be the most plausible place for the generation of bubbles, leading to a signal comparable to observations. This conclusion is supported by thermodynamic arguments and by RADAR properties of a bubbly column. The latter are also valid in the case of bubble plumes, due to gas leaking from the sea floor.

  15. TCSP ER-2 DOPPLER RADAR (EDOP) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The TCSP ER-2 DOPPLER RADAR (EDOP) dataset was collected by the ER-2 Doppler radar (EDOP), which is an X-band (9.6 GHz) Doppler radar mounted in the nose of the ER-2...

  16. CAMEX-4 ER-2 DOPPLER RADAR V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The CAMEX-4 ER-2 Doppler Radar dataset was collected by the ER-2 Doppler radar (EDOP), which is an X-band (9.6 GHz) Doppler radar mounted in the nose of ER-2. The...

  17. Radar micro-doppler signatures processing and applications

    CERN Document Server

    Chen, Victor C; Miceli, William J

    2014-01-01

    Radar Micro-Doppler Signatures: Processing and applications concentrates on the processing and application of radar micro-Doppler signatures in real world situations, providing readers with a good working knowledge on a variety of applications of radar micro-Doppler signatures.

  18. Significant wave height retrieval from synthetic radar images

    NARCIS (Netherlands)

    Wijaya, Andreas Parama; van Groesen, Embrecht W.C.

    2014-01-01

    In many offshore activities radar imagery is used to observe and predict ocean waves. An important issue in analyzing the radar images is to resolve the significant wave height. Different from 3DFFT methods that use an estimate related to the square root of the signal-to-noise ratio of radar images,

  19. Forward scatter radar for detection of moving people inside buildings

    NARCIS (Netherlands)

    Wit, J.J.M. de; Rossum, W.L. van

    2017-01-01

    Through-wall radar offers capabilities that allow an important contribution to inside-building awareness, such as target detection and tracking. However, reliable radar tracking of people inside a building is not a trivial task. In monostatic operation, radar measures the backscatter from people

  20. Forward scatter radar for remote intelligence of building interiors

    NARCIS (Netherlands)

    Rossum, W.L. van; Wit, J.J.M. de

    2017-01-01

    Through-wall radar allows for remote intelligence of building interiors including stand-off detection and tracking of persons inside a building. However, reliable radar tracking of people inside a building is not trivial. Conventional, monostatic through-wall radar measures the backscatter of moving

  1. Detection performance improvement of FMCW radar using frequency shift

    NARCIS (Netherlands)

    Wu, Y.; Linnartz, J.P.M.G.

    2011-01-01

    Frequency modulated continuous wave (FMCW) radars have been widely used for measuring target range and speed. In this paper, we present a mathematical model that quantifies the system-level performance of FMCW radar systems. In FMCW radar, the target range is measured through measuring the beat

  2. 14 CFR 125.223 - Airborne weather radar equipment requirements.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Airborne weather radar equipment... Equipment Requirements § 125.223 Airborne weather radar equipment requirements. (a) No person may operate an airplane governed by this part in passenger-carrying operations unless approved airborne weather radar...

  3. 14 CFR 121.357 - Airborne weather radar equipment requirements.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Airborne weather radar equipment... § 121.357 Airborne weather radar equipment requirements. (a) No person may operate any transport... December 31, 1964, unless approved airborne weather radar equipment has been installed in the airplane. (b...

  4. Block diagrams of the radar interface and control unit

    Science.gov (United States)

    Collier, J. W.

    1989-01-01

    The Interface and Control Unit is the heart of the radar module, which occupies one complex channel of the High-Speed Data Acquisition System of the Goldstone Solar System Radar. Block diagrams of the interface unit are presented as an aid to understanding its operation and interconnections to the rest of the radar module.

  5. Vertical Pointing Weather Radar for Built-up Urban Areas

    DEFF Research Database (Denmark)

    Rasmussen, Michael R.; Thorndahl, Søren; Schaarup-Jensen, Kjeld

    2008-01-01

      A cost effective vertical pointing X-band weather radar (VPR) has been tested for measurement of precipitation in urban areas. Stationary tests indicate that the VPR performs well compared to horizontal weather radars, such as the local area weather radars (LAWR). The test illustrated...

  6. Radar Observations of Main-Belt M-class Asteroids

    NARCIS (Netherlands)

    Shepard, Michael K.; Clark, B. E.; Ockert-Bell, M.; Nolan, M. C.; Howell, E. S.; Magri, C.; Giorgini, J. D.; Benner, L. A. M.; Ostro, S. J.; Harris, A. W.; Warner, B. D.; Stephens, R. D.; Mueller, M.

    2009-01-01

    Using the S-band radar at Arecibo Observatory, we have observed 19 Tholen M-class asteroids. The mean radar albedo for all our targets is 0.28 ± 0.13, considerably higher than the mean radar albedo of every other class (Magri et al. 2007, Icarus 186, 126-151). We find approximately one-third (six)

  7. Implementation and validation of the ISMAR High Frequency Coastal Radar Network in the Gulf of Manfredonia (Mediterranean Sea)

    DEFF Research Database (Denmark)

    Corgnati, Lorenzo; Mantovani, Carlo; Griffa, Annalisa

    2018-01-01

    In this paper a High Frequency (HF) Coastal Radar Network is described, established and maintained by the Institute of Marine Sciences (ISMAR) of the National Research Council of Italy (CNR) for the measurement of surface current velocities in the Gulf of Manfredonia, located in the semi......-enclosed Adriatic Sea (Mediterranean Sea), during the period 2013-2015. The network consisted of four HF radars that provided hourly sea surface velocity data in real-time mode in a netCDF format compliant to the Climate and Forecast Metadata Conventions CF-1.6 and to the INSPIRE directive. The hourly netCDF files...... are disseminated via a THREDDS catalog supporting OGC compliant distributions and protocols for data visualization, metadata interrogation and data download. HF radar velocity data were validated using in situ velocity measurements by GPS-tracked surface drifters deployed within the radar footprint. The results...

  8. Radar meteors range distribution model. II. Shower flux density and mass distribution index

    Czech Academy of Sciences Publication Activity Database

    Pecinová, Drahomíra; Pecina, Petr

    2007-01-01

    Roč. 37, č. 2 (2007), s. 107-124 ISSN 1335-1842 R&D Projects: GA ČR GA205/03/1405 Institutional research plan: CEZ:AV0Z10030501 Keywords : physics of meteors * radar meteors * range distribution Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  9. Radar meteors range distribution model. III. Ablation, shape-density and self-similarity parameters

    Czech Academy of Sciences Publication Activity Database

    Pecinová, Drahomíra; Pecina, Petr

    2007-01-01

    Roč. 37, č. 3 (2007), s. 147-160 ISSN 1335-1842 R&D Projects: GA ČR GA205/03/1405 Institutional research plan: CEZ:AV0Z10030501 Keywords : physics of meteors * radar meteors * range distribution Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  10. Ondřejov radar observations of Leonid shower activity in 2000-2002

    Czech Academy of Sciences Publication Activity Database

    Pecina, Petr; Pecinová, Drahomíra

    2004-01-01

    Roč. 426, č. 3 (2004), s. 1111-1117 ISSN 0004-6361 R&D Projects: GA AV ČR KSK3012103 Institutional research plan: CEZ:AV0Z1003909 Keywords : Leonid meteor * radar observations Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 3.694, year: 2004

  11. Design of an ultra-wideband ground-penetrating radar system using impulse radiating antennas

    NARCIS (Netherlands)

    Rhebergen, J.B.; Zwamborn, A.P.M.; Giri, D.V.

    1998-01-01

    At TNO-FEL, one of the research programs is to explore the use of ultra-wideband (UWB) electromagnetic fields in a bi-static ground-penetrating radar (GPR) system for the detection, location and identification of buried items of unexploded ordnance (e.g. land mines). In the present paper we describe

  12. Design of an ultra-wideband ground-penetrating radar system using impulse radiating antennas

    NARCIS (Netherlands)

    Rhebergen, J.B.; Zwamborn, A.P.M.; Giri, D.V.

    1999-01-01

    At TNO-FEL, one of the research programs is to explore the use of ultra-wideband (UWB) electromagnetic fields in a bi-static ground-penetrating radar (GPR) system for the detection, location and identification of buried items of unexploded ordnance (e.g. land mines). In the present paper we describe

  13. Atomic bomb made in Germany. Geo-radar measurements provide new insights

    International Nuclear Information System (INIS)

    Hauk, Rolf-Guenter; Focken, Christel

    2017-01-01

    The authors describe new geo radar measurements In Jonastal and discuss the results in relation to rumors on German efforts to build an atomic bond during the Second World War. The book includes available documentation on German and American research and technological activities (Manhattan project).

  14. Effectiveness of WRF wind direction for retrieving coastal sea surface wind from synthetic aperture radar

    DEFF Research Database (Denmark)

    Takeyama, Yuko; Ohsawa, Teruo; Kozai, Katsutoshi

    2013-01-01

    Wind direction is required as input to the geophysical model function (GMF) for the retrieval of sea surface wind speed from a synthetic aperture radar (SAR) images. The present study verifies the effectiveness of using the wind direction obtained from the weather research and forecasting model (...

  15. Assimilation of radar reflectivity into the LM COSMO model with a high horizontal resolution

    Czech Academy of Sciences Publication Activity Database

    Sokol, Zbyněk; Řezáčová, Daniela

    2006-01-01

    Roč. 13, č. 4 (2006), s. 317-330 ISSN 1350-4827 R&D Projects: GA ČR GA205/04/0114 Institutional research plan: CEZ:AV0Z30420517 Keywords : precipitation forecast * assimilation * radar reflectivity * NWP model * local storm Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 0.453, year: 2006

  16. Radar and optical observations and physical modeling of near-Earth Asteroid 10115 (1992 SK)

    Czech Academy of Sciences Publication Activity Database

    Busch, M.; Ostro, S. J.; Benner, L. A. M.; Giorgini, J. D.; Jurgens, R. F.; Rose, R.; Magri, C.; Pravec, Petr; Scheeres, D.J.; Broschart, S.B.

    2006-01-01

    Roč. 181, č. 1 (2006), s. 145-155 ISSN 0019-1035 R&D Projects: GA ČR(CZ) GA205/05/0604; GA AV ČR IAA3003204 Institutional research plan: CEZ:AV0Z10030501 Keywords : asteroids * radar * rotation Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 3.151, year: 2006

  17. Radar Imaging of Binary Near-Earth Asteroid (66391) 1999 KW4

    Czech Academy of Sciences Publication Activity Database

    Ostro, S. J.; Margot, J. L.; Benner, L. A. M.; Giorgini, J. D.; Scheeres, D.J.; Fahnestock, E.G.; Broschart, S.B.; Bellerose, J.; Nolan, M. C.; Magri, C.; Pravec, Petr; Scheirich, Peter; Rose, R.; Jurgens, R. F.; De Jong, E. M.; Suzuki, S.

    2006-01-01

    Roč. 314, č. 5803 (2006), s. 1276-1280 ISSN 0036-8075 R&D Projects: GA ČR GA205/05/0604 Institutional research plan: CEZ:AV0Z10030501 Keywords : binary asteroid * radar imaging Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 30.028, year: 2006

  18. Development of Radar Control system for Multi-mode Active Phased Array Radar for atmospheric probing

    Science.gov (United States)

    Yasodha, Polisetti; Jayaraman, Achuthan; Thriveni, A.

    2016-07-01

    Modern multi-mode active phased array radars require highly efficient radar control system for hassle free real time radar operation. The requirement comes due to the distributed architecture of the active phased array radar, where each antenna element in the array is connected to a dedicated Transmit-Receive (TR) module. Controlling the TR modules, which are generally few hundreds in number, and functioning them in synchronisation, is a huge task during real time radar operation and should be handled with utmost care. Indian MST Radar, located at NARL, Gadanki, which is established during early 90's, as an outcome of the middle atmospheric program, is a remote sensing instrument for probing the atmosphere. This radar has a semi-active array, consisting of 1024 antenna elements, with limited beam steering, possible only along the principle planes. To overcome the limitations and difficulties, the radar is being augmented into fully active phased array, to accomplish beam agility and multi-mode operations. Each antenna element is excited with a dedicated 1 kW TR module, located in the field and enables to position the radar beam within 20° conical volume. A multi-channel receiver makes the radar to operate in various modes like Doppler Beam Swinging (DBS), Spaced Antenna (SA), Frequency Domain Interferometry (FDI) etc. Present work describes the real-time radar control (RC) system for the above described active phased array radar. The radar control system consists of a Spartan 6 FPGA based Timing and Control Signal Generator (TCSG), and a computer containing the software for controlling all the subsystems of the radar during real-time radar operation and also for calibrating the radar. The main function of the TCSG is to generate the control and timing waveforms required for various subsystems of the radar. Important components of the RC system software are (i) TR module configuring software which does programming, controlling and health parameter monitoring of the

  19. Using microwave Doppler radar in automated manufacturing applications

    Science.gov (United States)

    Smith, Gregory C.

    Since the beginning of the Industrial Revolution, manufacturers worldwide have used automation to improve productivity, gain market share, and meet growing or changing consumer demand for manufactured products. To stimulate further industrial productivity, manufacturers need more advanced automation technologies: "smart" part handling systems, automated assembly machines, CNC machine tools, and industrial robots that use new sensor technologies, advanced control systems, and intelligent decision-making algorithms to "see," "hear," "feel," and "think" at the levels needed to handle complex manufacturing tasks without human intervention. The investigator's dissertation offers three methods that could help make "smart" CNC machine tools and industrial robots possible: (1) A method for detecting acoustic emission using a microwave Doppler radar detector, (2) A method for detecting tool wear on a CNC lathe using a Doppler radar detector, and (3) An online non-contact method for detecting industrial robot position errors using a microwave Doppler radar motion detector. The dissertation studies indicate that microwave Doppler radar could be quite useful in automated manufacturing applications. In particular, the methods developed may help solve two difficult problems that hinder further progress in automating manufacturing processes: (1) Automating metal-cutting operations on CNC machine tools by providing a reliable non-contact method for detecting tool wear, and (2) Fully automating robotic manufacturing tasks by providing a reliable low-cost non-contact method for detecting on-line position errors. In addition, the studies offer a general non-contact method for detecting acoustic emission that may be useful in many other manufacturing and non-manufacturing areas, as well (e.g., monitoring and nondestructively testing structures, materials, manufacturing processes, and devices). By advancing the state of the art in manufacturing automation, the studies may help

  20. Study to investigate and evaluate means of optimizing the radar function. [systems engineering of pulse radar for the space shuttle

    Science.gov (United States)

    1975-01-01

    The investigations for a rendezvous radar system design and an integrated radar/communication system design are presented. Based on these investigations, system block diagrams are given and system parameters are optimized for the noncoherent pulse and coherent pulse Doppler radar modulation types. Both cooperative (transponder) and passive radar operation are examined including the optimization of the corresponding transponder design for the cooperative mode of operation.

  1. Radar cross-section (RCS) analysis of high frequency surface wave radar targets

    OpenAIRE

    ÇAKIR, Gonca; SEVGİ, Levent

    2010-01-01

    Realistic high frequency surface wave radar (HFSWR) targets are investigated numerically in terms of electromagnetic wave -- target interactions. Radar cross sections (RCS) of these targets are simulated via both the finite-difference time-domain (FDTD) method and the Method of Moments (MoM). The virtual RCS prediction tool that was introduced in previous work is used for these investigations. The virtual tool automatically creates the discrete FDTD model of the target under investi...

  2. Tree root mapping with ground penetrating radar

    CSIR Research Space (South Africa)

    Van Schoor, Abraham M

    2009-09-01

    Full Text Available In this paper, the application of ground penetrating radar (GPR) for the mapping of near surface tree roots is demonstrated. GPR enables tree roots to be mapped in a non-destructive and cost-effective manner and is therefore a useful prospecting...

  3. Tabu search for target-radar assignment

    DEFF Research Database (Denmark)

    Hindsberger, Magnus; Vidal, Rene Victor Valqui

    2000-01-01

    In the paper the problem of assigning air-defense illumination radars to enemy targets is presented. A tabu search metaheuristic solution is described and the results achieved are compared to those of other heuristic approaches, implementation and experimental aspects are discussed. It is argued ...

  4. Multiple hypothesis clustering in radar plot extraction

    NARCIS (Netherlands)

    Huizing, A.G.; Theil, A.; Dorp, Ph. van; Ligthart, L.P.

    1995-01-01

    False plots and plots with inaccurate range and Doppler estimates may severely degrade the performance of tracking algorithms in radar systems. This paper describes how a multiple hypothesis clustering technique can be applied to mitigate the problems involved in plot extraction. The measures of

  5. Monitoring civil infrastructure using satellite radar interferometry

    NARCIS (Netherlands)

    Chang, L.

    2015-01-01

    Satellite radar interferometry (InSAR) is a precise and efficient technique to monitor deformation on Earth with millimeter precision. Most InSAR applications focus on geophysical phenomena, such as earthquakes, volcanoes, or subsidence. Monitoring civil infrastructure with InSAR is relatively new,

  6. Aircraft height estimation using 2-D radar

    CSIR Research Space (South Africa)

    Hakl, H

    2010-01-01

    Full Text Available A method to infer height information from an aircraft tracked with a single 2-D search radar is presented. The method assumes level flight in the target aircraft and a good estimate of the speed of the aircraft. The method yields good results...

  7. Minefield overwatch using moving target indicator radar

    Science.gov (United States)

    Donadio, Anthony; Ewing, Robert; Kenneally, William J.; Santapietro, John J.

    1999-07-01

    Traditional antipersonnel land mines are an effective military tool, but they are unable to distinguish friend from foe, or civilian from military personnel. The concept described here uses an advanced moving target indicator (MTI) radar to scan the minefield in order to detect movement towards or within the minefield, coupled with visual identification by a human operator and a communication link for command and control. Selected mines in the minefield can then be activated by means of the command link. In order to demonstrate this concept, a 3D, interactive simulation has been developed. This simulation builds on previous work by integrating a detailed analytical model of an MTI radar. This model has been tailored to the specific application of detection of slowly moving dismounted entities immersed in ground clutter. The model incorporates the effects of internal scatterer motion and antenna scanning modulation in order to provide a realistic representation of the detection problem in this environment. The angle information on the MTI target detection is then passed to a virtual 3D sight which cues a human operator to the target location. In addition, radar propagation effects and an experimental design in which the radar itself is used as a command link are explored.

  8. Space communication and radar with lasers

    NARCIS (Netherlands)

    Witteman, W.J.

    2005-01-01

    Sensitive heterodyne detection with lasers applied .to radar and satellite communication is seriously hampered by the large electronic bandwidth due to random Doppler shift and frequency instability. These drawbacks can be circumvented by dual signal heterodyne detection. The system consists of

  9. Sixteenth International Laser Radar Conference, Part 2

    International Nuclear Information System (INIS)

    Mccormick, M.P.

    1992-07-01

    Given here are extended abstracts of papers presented at the 16th International Laser Radar Conference, held in Cambridge, Massachusetts, July 20-24, 1992. Topics discussed include the Mt. Pinatubo volcanic dust laser observations, global change, ozone measurements, Earth mesospheric measurements, wind measurements, imaging, ranging, water vapor measurements, and laser devices and technology

  10. EISCAT as a tristatic auroral radar

    International Nuclear Information System (INIS)

    Schlegel, K.; Moorcroft, D.R.

    1989-01-01

    The authors have used the European Incoherent Scatter radar (EISCAT) in a mode which allows them to use it as a tristatic auroral radar. Observing at an elevation of less than 10 degree with the Tromsoe beam, they achieved magnetic aspect angles between 4 degree and 6 degree at 105 km altitude and recorded coherent echoes simultaneously from all three sites. The backscattered power for these echoes is up to 3 orders of magnitude higher than typical incoherent scatter echoes. Contrary to most existing auroral radars, they can calibrate the coherent echo strength and thus determine absolute values of the coherent backscatter cross section. Moreover, switching the common volume in short time intervals from E to F region heights, permits the determination of the E x B drift vector almost simultaneously with the E region coherent scattering measurements. This opens unique possibilities to study the E region plasma instabilities and their driving force. The main aim of this paper is to describe the capabilities of EISCAT as an auroral radar and to present and discuss results in terms of coherent backscatter cross sections, coherent spectra shape, irregularity phase velocities, and aspect angle dependence. In forthcoming papers several of these topics will be explored in more detail

  11. Radar Doppler Processing with Nonuniform Sampling.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-07-01

    Conventional signal processing to estimate radar Doppler frequency often assumes uniform pulse/sample spacing. This is for the convenience of t he processing. More recent performance enhancements in processor capability allow optimally processing nonuniform pulse/sample spacing, thereby overcoming some of the baggage that attends uniform sampling, such as Doppler ambiguity and SNR losses due to sidelobe control measures.

  12. A 24GHz Radar Receiver in CMOS

    NARCIS (Netherlands)

    Kwok, K.C.

    2015-01-01

    This thesis investigates the system design and circuit implementation of a 24GHz-band short-range radar receiver in CMOS technology. The propagation and penetration properties of EM wave offer the possibility of non-contact based remote sensing and through-the-wall imaging of distance stationary or

  13. Transmitter passband requirements for imaging radar.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter

    2012-12-01

    In high-power microwave power amplifiers for radar, distortion in both amplitude and phase should generally be expected. Phase distortions can be readily equalized. Some amplitude distortions are more problematic than others. In general, especially for SAR using LFM chirps, low frequency modulations such as gain slopes can be tolerated much better than multiple cycles of ripple across the passband of the waveform.

  14. Slope stability radar for monitoring mine walls

    Science.gov (United States)

    Reeves, Bryan; Noon, David A.; Stickley, Glen F.; Longstaff, Dennis

    2001-11-01

    Determining slope stability in a mining operation is an important task. This is especially true when the mine workings are close to a potentially unstable slope. A common technique to determine slope stability is to monitor the small precursory movements, which occur prior to collapse. The slope stability radar has been developed to remotely scan a rock slope to continuously monitor the spatial deformation of the face. Using differential radar interferometry, the system can detect deformation movements of a rough wall with sub-millimeter accuracy, and with high spatial and temporal resolution. The effects of atmospheric variations and spurious signals can be reduced via signal processing means. The advantage of radar over other monitoring techniques is that it provides full area coverage without the need for mounted reflectors or equipment on the wall. In addition, the radar waves adequately penetrate through rain, dust and smoke to give reliable measurements, twenty-four hours a day. The system has been trialed at three open-cut coal mines in Australia, which demonstrated the potential for real-time monitoring of slope stability during active mining operations.

  15. Marine X-band Weather Radar Data Calibration

    DEFF Research Database (Denmark)

    Thorndahl, Søren Liedtke; Rasmussen, Michael R.

    2012-01-01

    estimates. This paper presents some of the challenges in small marine X-band radar calibration by comparing three calibration procedures for assessing the relationship between radar and rain gauge data. Validation shows similar results for precipitation volumes but more diverse results on peak rain......Application of weather radar data in urban hydrology is evolving and radar data is now applied for both modelling, analysis, and real time control purposes. In these contexts, it is allimportant that the radar data is well calibrated and adjusted in order to obtain valid quantitative precipitation...

  16. Temperature sheets and aspect sensitive radar echoes

    Directory of Open Access Journals (Sweden)

    H. Luce

    Full Text Available here have been years of discussion and controversy about the existence of very thin and stable temperature sheets and their relationship to the VHF radar aspect sensitivity. It is only recently that very high-resolution in situ temperature observations have brought credence to the reality and ubiquity of these structures in the free atmosphere and to their contribution to radar echo enhancements along the vertical. Indeed, measurements with very high-resolution sensors are still extremely rare and rather difficult to obtain outside of the planetary boundary layer. They have only been carried out up to the lower stratosphere by Service d’A´ eronomie (CNRS, France for about 10 years. The controversy also persisted due to the volume resolution of the (Mesosphere-Stratosphere-Troposphere VHF radars which is coarse with respect to sheet thickness, although widely sufficient for meteorological or mesoscale investigations. The contribution within the range gate of many of these structures, which are advected by the wind, and decay and grow at different instants and could be distorted either by internal gravity waves or turbulence fields, could lead to radar echoes with statistical properties similar to those produced by anisotropic turbulence. Some questions thus remain regarding the manner in which temperature sheets contribute to VHF radar echoes. In particular, the zenithal and azimuthal angular dependence of the echo power may not only be produced by diffuse reflection on stable distorted or corrugated sheets, but also by extra contributions from anisotropic turbulence occurring in the stratified atmosphere. Thus, for several years, efforts have been put forth to improve the radar height resolution in order to better describe thin structures. Frequency interferometric techniques are widely used and have been recently further developed with the implementation of high-resolution data processings. We begin by reviewing briefly some characteristics

  17. Temperature sheets and aspect sensitive radar echoes

    Directory of Open Access Journals (Sweden)

    H. Luce

    2001-08-01

    Full Text Available here have been years of discussion and controversy about the existence of very thin and stable temperature sheets and their relationship to the VHF radar aspect sensitivity. It is only recently that very high-resolution in situ temperature observations have brought credence to the reality and ubiquity of these structures in the free atmosphere and to their contribution to radar echo enhancements along the vertical. Indeed, measurements with very high-resolution sensors are still extremely rare and rather difficult to obtain outside of the planetary boundary layer. They have only been carried out up to the lower stratosphere by Service d’A´ eronomie (CNRS, France for about 10 years. The controversy also persisted due to the volume resolution of the (Mesosphere-Stratosphere-Troposphere VHF radars which is coarse with respect to sheet thickness, although widely sufficient for meteorological or mesoscale investigations. The contribution within the range gate of many of these structures, which are advected by the wind, and decay and grow at different instants and could be distorted either by internal gravity waves or turbulence fields, could lead to radar echoes with statistical properties similar to those produced by anisotropic turbulence. Some questions thus remain regarding the manner in which temperature sheets contribute to VHF radar echoes. In particular, the zenithal and azimuthal angular dependence of the echo power may not only be produced by diffuse reflection on stable distorted or corrugated sheets, but also by extra contributions from anisotropic turbulence occurring in the stratified atmosphere. Thus, for several years, efforts have been put forth to improve the radar height resolution in order to better describe thin structures. Frequency interferometric techniques are widely used and have been recently further developed with the implementation of high-resolution data processings. We begin by reviewing briefly some characteristics

  18. Space Radar Image of Manaus, Brazil

    Science.gov (United States)

    1999-01-01

    These two images were created using data from the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR). On the left is a false-color image of Manaus, Brazil acquired April 12, 1994, onboard space shuttle Endeavour. In the center of this image is the Solimoes River just west of Manaus before it combines with the Rio Negro to form the Amazon River. The scene is around 8 by 8 kilometers (5 by 5 miles) with north toward the top. The radar image was produced in L-band where red areas correspond to high backscatter at HH polarization, while green areas exhibit high backscatter at HV polarization. Blue areas show low backscatter at VV polarization. The image on the right is a classification map showing the extent of flooding beneath the forest canopy. The classification map was developed by SIR-C/X-SAR science team members at the University of California,Santa Barbara. The map uses the L-HH, L-HV, and L-VV images to classify the radar image into six categories: Red flooded forest Green unflooded tropical rain forest Blue open water, Amazon river Yellow unflooded fields, some floating grasses Gray flooded shrubs Black floating and flooded grasses Data like these help scientists evaluate flood damage on a global scale. Floods are highly episodic and much of the area inundated is often tree-covered. Spaceborne Imaging Radar-C and X-Synthetic Aperture Radar (SIR-C/X-SAR) is part of NASA's Mission to Planet Earth. The radars illuminate Earth with microwaves allowing detailed observations at any time, regardless of weather or sunlight conditions. SIR-C/X-SAR uses three microwave wavelengths: L-band (24 cm), C-band (6 cm) and X-band (3 cm). The multi-frequency data will be used by the international scientific community to better understand the global environment and how it is changing. The SIR-C/X-SAR data, complemented by aircraft and ground studies, will give scientists clearer insights into those environmental changes which are caused by nature and those

  19. Investigation of Weather Radar Quantitative Precipitation Estimation Methodologies in Complex Orography

    Directory of Open Access Journals (Sweden)

    Mario Montopoli

    2017-02-01

    vertical extrapolations. In this work, a definition of complex orography is also given, introducing a radar orography index to objectively quantify the degree of terrain complexity when dealing with radar QPE in heterogeneous environmental scenarios. Three case studies observed by the research C-band polarization agility Doppler radar named Polar 55C, managed by the Institute of Atmospheric Sciences and Climate (ISAC at the National Research Council of Italy (CNR, were used to prove the concept of VPR. Our results indicate that the combined algorithm, which merges together differential phase shift (Kdp, single polarization reflectivity factor (Zhh, and differential reflectivity (Zdr, once accurately processed, in most cases performs better among those tested and those that make use of Zhh alone, Kdp alone, and Zhh, and Zdr. Improvements greater than 25% are found for the total rain accumulations in terms of normalized bias when the VPR extrapolation is applied.

  20. Space Radar Image of County Kerry, Ireland

    Science.gov (United States)

    1994-01-01

    The Iveragh Peninsula, one of the four peninsulas in southwestern Ireland, is shown in this spaceborne radar image. The lakes of Killarney National Park are the green patches on the left side of the image. The mountains to the right of the lakes include the highest peaks (1,036 meters or 3,400 feet) in Ireland. The patchwork patterns between the mountains are areas of farming and grazing. The delicate patterns in the water are caused by refraction of ocean waves around the peninsula edges and islands, including Skellig Rocks at the right edge of the image. The Skelligs are home to a 15th century monastery and flocks of puffins. The region is part of County Kerry and includes a road called the 'Ring of Kerry' that is one of the most famous tourist routes in Ireland. This image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar (SIR-C/X-SAR) onboard the Space Shuttle Endeavour on April 12, 1994. The image is 82 kilometers by 42 kilometers (51 miles by 26 miles) and is centered at 52.0 degrees north latitude, 9.9 degrees west longitude. North is toward the lower left. The colors are assigned to different radar frequencies and polarizations of the radar as follows: red is L-band, horizontally transmitted and received; green is L-band, vertically transmitted and received; and blue is C-band, vertically transmitted and received. SIR-C/X-SAR, a joint mission of the German, Italian and United States space agencies, is part of NASA's Mission to Planet Earth program.

  1. Detecting and mitigating wind turbine clutter for airspace radar systems.

    Science.gov (United States)

    Wang, Wen-Qin

    2013-01-01

    It is well recognized that a wind turbine has a large radar cross-section (RCS) and, due to the movement of the blades, the wind turbine will generate a Doppler frequency shift. This scattering behavior may cause severe interferences on existing radar systems including static ground-based radars and spaceborne or airborne radars. To resolve this problem, efficient techniques or algorithms should be developed to mitigate the effects of wind farms on radars. Herein, one transponder-based mitigation technique is presented. The transponder is not a new concept, which has been proposed for calibrating high-resolution imaging radars. It modulates the radar signal in a manner that the retransmitted signals can be separated from the scene echoes. As wind farms often occupy only a small area, mitigation processing in the whole radar operation will be redundant and cost inefficient. Hence, this paper uses a transponder to determine whether the radar is impacted by the wind farms. If so, the effects of wind farms are then mitigated with subsequent Kalman filtering or plot target extraction algorithms. Taking airborne synthetic aperture radar (SAR) and pulse Doppler radar as the examples, this paper provides the corresponding system configuration and processing algorithms. The effectiveness of the mitigation technique is validated by numerical simulation results.

  2. Ground and Space Radar Volume Matching and Comparison Software

    Science.gov (United States)

    Morris, Kenneth; Schwaller, Mathew

    2010-01-01

    This software enables easy comparison of ground- and space-based radar observations. The software was initially designed to compare ground radar reflectivity from operational, ground based Sand C-band meteorological radars with comparable measurements from the Tropical Rainfall Measuring Mission (TRMM) satellite s Precipitation Radar (PR) instrument. The software is also applicable to other ground-based and space-based radars. The ground and space radar volume matching and comparison software was developed in response to requirements defined by the Ground Validation System (GVS) of Goddard s Global Precipitation Mission (GPM) project. This software innovation is specifically concerned with simplifying the comparison of ground- and spacebased radar measurements for the purpose of GPM algorithm and data product validation. This software is unique in that it provides an operational environment to routinely create comparison products, and uses a direct geometric approach to derive common volumes of space- and ground-based radar data. In this approach, spatially coincident volumes are defined by the intersection of individual space-based Precipitation Radar rays with the each of the conical elevation sweeps of the ground radar. Thus, the resampled volume elements of the space and ground radar reflectivity can be directly compared to one another.

  3. Detecting and Mitigating Wind Turbine Clutter for Airspace Radar Systems

    Directory of Open Access Journals (Sweden)

    Wen-Qin Wang

    2013-01-01

    Full Text Available It is well recognized that a wind turbine has a large radar cross-section (RCS and, due to the movement of the blades, the wind turbine will generate a Doppler frequency shift. This scattering behavior may cause severe interferences on existing radar systems including static ground-based radars and spaceborne or airborne radars. To resolve this problem, efficient techniques or algorithms should be developed to mitigate the effects of wind farms on radars. Herein, one transponder-based mitigation technique is presented. The transponder is not a new concept, which has been proposed for calibrating high-resolution imaging radars. It modulates the radar signal in a manner that the retransmitted signals can be separated from the scene echoes. As wind farms often occupy only a small area, mitigation processing in the whole radar operation will be redundant and cost inefficient. Hence, this paper uses a transponder to determine whether the radar is impacted by the wind farms. If so, the effects of wind farms are then mitigated with subsequent Kalman filtering or plot target extraction algorithms. Taking airborne synthetic aperture radar (SAR and pulse Doppler radar as the examples, this paper provides the corresponding system configuration and processing algorithms. The effectiveness of the mitigation technique is validated by numerical simulation results.

  4. Development of Radar-Satellite Blended QPF (Quantitative Precipitation Forecast) Technique for heavy rainfall

    Science.gov (United States)

    Jang, Sangmin; Yoon, Sunkwon; Rhee, Jinyoung; Park, Kyungwon

    2016-04-01

    Due to the recent extreme weather and climate change, a frequency and size of localized heavy rainfall increases and it may bring various hazards including sediment-related disasters, flooding and inundation. To prevent and mitigate damage from such disasters, very short range forecasting and nowcasting of precipitation amounts are very important. Weather radar data very useful in monitoring and forecasting because weather radar has high resolution in spatial and temporal. Generally, extrapolation based on the motion vector is the best method of precipitation forecasting using radar rainfall data for a time frame within a few hours from the present. However, there is a need for improvement due to the radar rainfall being less accurate than rain-gauge on surface. To improve the radar rainfall and to take advantage of the COMS (Communication, Ocean and Meteorological Satellite) data, a technique to blend the different data types for very short range forecasting purposes was developed in the present study. The motion vector of precipitation systems are estimated using 1.5km CAPPI (Constant Altitude Plan Position Indicator) reflectivity by pattern matching method, which indicates the systems' direction and speed of movement and blended radar-COMS rain field is used for initial data. Since the original horizontal resolution of COMS is 4 km while that of radar is about 1 km, spatial downscaling technique is used to downscale the COMS data from 4 to 1 km pixels in order to match with the radar data. The accuracies of rainfall forecasting data were verified utilizing AWS (Automatic Weather System) observed data for an extreme rainfall occurred in the southern part of Korean Peninsula on 25 August 2014. The results of this study will be used as input data for an urban stream real-time flood early warning system and a prediction model of landslide. Acknowledgement This research was supported by a grant (13SCIPS04) from Smart Civil Infrastructure Research Program funded by

  5. Space Radar Image of Central African Gorilla Habitat

    Science.gov (United States)

    1999-01-01

    This is a false-color radar image of Central Africa, showing the Virunga Volcano chain along the borders of Rwanda, Zaire and Uganda. This area is home to the endangered mountain gorillas. This C-band L-band image was acquired on April 12, 1994, on orbit 58 of space shuttle Endeavour by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar (SIR-C/X-SAR). The area is centered at about 1.75 degrees south latitude and 29.5 degrees east longitude. The image covers an area 58 kilometers by 178 kilometers (48 miles by 178 miles). The false-color composite is created by displaying the L-band HH return in red, the L-band HV return in green and the C-band HH return in blue. The dark area in the bottom of the image is Lake Kivu, which forms the border between Zaire (to the left) and Rwanda (to the right). The airport at Goma, Zaire is shown as a dark line just above the lake in the bottom left corner of the image. Volcanic flows from the 1977 eruption of Mt. Nyiragongo are shown just north of the airport. Mt. Nyiragongo is not visible in this image because it is located just to the left of the image swath. Very fluid lava flows from the 1977 eruption killed 70 people. Mt. Nyiragongo is currently erupting (August 1994) and will be a target of observation during the second flight of SIR-C/X-SAR. The large volcano in the center of the image is Mt. Karisimbi (4,500 meters or 14,800 feet). This radar image highlights subtle differences in the vegetation and volcanic flows of the region. The faint lines shown in the purple regions are believed to be the result of agriculture terracing by the people who live in the region. The vegetation types are an important factor in the habitat of the endangered mountain gorillas. Researchers at Rutgers University in New Jersey and the Dian Fossey Gorilla Fund in London will use this data to produce vegetation maps of the area to aid in their study of the remaining 650 gorillas in the region. SIR-C was developed by NASA's Jet

  6. Development Of Signal Detection For Radar Navigation System

    Directory of Open Access Journals (Sweden)

    Theingi Win Hlaing

    2017-09-01

    Full Text Available This paper aims to evaluate the performance of target detection in the presence of sea clutter. Radar detection of a background of unwanted clutter due to echoes from sea clutter or land is a problem of interest in the radar field. Radar detector has been developed by assuming the radar clutter is Gaussian distributed. However as technology emerges the radar distribution is seen to deviates from the Gaussian assumption. Thus detectors designs based on Gaussian assumption are no longer optimum for detection in non-Gaussian nature. The theory of target detection in Gaussian distributed clutter has been well established and the closed form of the detection performances can be easily obtained. However that is not the case in non-Gaussian clutter distributions. The operation of radar detection is determined by radar detection theory with different types of Swerling target models such as Swerling I II III IV and V. By using MATLAB these signal detection techniques are developed.

  7. Developing an Efficient and Cost Effective Ground-Penetrating Radar Field Methodology for Subsurface Exploration and Mapping of Cultural Resources on Public Lands

    National Research Council Canada - National Science Library

    Conyers, Lawrence B

    2006-01-01

    .... A new, emerging technology is the use of ground penetrating radar (GPR). However, in using this device due to the number of variables that can impact energy penetration and resolution, researchers are often not guaranteed a successful survey...

  8. Civil Engineering Applications of Ground Penetrating Radar in Finland

    Science.gov (United States)

    Pellinen, Terhi; Huuskonen-Snicker, Eeva; Olkkonen, Martta-Kaisa; Eskelinen, Pekka

    2014-05-01

    Ground penetrating radar (GPR) has been used in Finland since 1980's for civil engineering applications. First applications in this field were road surveys and dam inspections. Common GPR applications in road surveys include the thickness evaluation of the pavement, subgrade soil evaluation and evaluation of the soil moisture and frost susceptibility. Since the 1990's, GPR has been used in combination with other non-destructive testing (NDT) methods in road surveys. Recently, more GPR applications have been adopted, such as evaluating bridges, tunnels, railways and concrete elements. Nowadays, compared with other countries GPR is relatively widely used in Finland for road surveys. Quite many companies, universities and research centers in Finland have their own GPR equipment and are involved in the teaching and research of the GPR method. However, further research and promotion of the GPR techniques are still needed since GPR could be used more routinely. GPR has been used to evaluate the air void content of asphalt pavements for years. Air void content is an important quality measure of pavement condition for both the new and old asphalt pavements. The first Finnish guideline was released in 1999 for the method. Air void content is obtained from the GPR data by measuring the dielectric value as continuous record. To obtain air void content data, few pavement cores must be taken for calibration. Accuracy of the method is however questioned because there are other factors that affect the dielectric value of the asphalt layer, in addition to the air void content. Therefore, a research project is currently carried out at Aalto University in Finland. The overall objective is to investigate if the existing GPR technique used in Finland is accurate enough to be used as QC/QA tool in assessing the compaction of asphalt pavements. The project is funded by the Finnish Transport Agency. Further research interests at Aalto University include developing new microwave asphalt

  9. APPLICATION OF SENTINEL-1 RADAR DATA FOR MAPPING HARD-TO-REACH NORTHERN TERRITORIES

    Directory of Open Access Journals (Sweden)

    Е. А. Baldina

    2017-01-01

    Full Text Available The new European space satellites Sentinel-1A and 1B with C-band radars on board, launched in 2014 and 2016 respectively, provide regular radar data on the Earth’s surface with high temporal resolution. These new non-commercial data provides extensive opportunities for research of remote Arctic territories, poorly supplied with optical images due to cloud conditions. Difficulties in recognizing objects on radar images can be compensated for by the possibility of using multiple repeated surveys, which make it possible to identify areas of the terrain which are similar in character of changes. In the study, four Sentinel-1A images of the largest from the New Siberian islands – Kotelny – were used, which were acquired during the summer period from July 3 to August 20, 2015. After preprocessing aimed at improving the visual properties and coregistration of the multitemporal images, an automated clustering of the multitemporal image set was carried out. Clustering results were analyzed on comparison with additional sources of spatial information. Both specialized software for Sentinel-1 radar data processing - SNAP, and the GIS software complex ArcGIS were used. The latter provided the creation of the spatial data base for comparing the results of radar data processing and cartographic sources. The map of the territory zoning was obtained as clustering results which is based on the changes in the normalized radar cross section (sigma nought over the summer period, and the approximate correspondence of the areas to the main types of the relief and landscapes of the island was established.

  10. Plans for the Meter Class Autonomous Telescope and Potential Coordinated Measurements with Kwajalein Radars

    Science.gov (United States)

    Stansberry, Gene; Kervin, Paul; Mulrooney, Mark

    2010-01-01

    The National Aeronautics and Space Administration's (NASA) Orbital Debris Program Office is teaming with the US Air Force Research Laboratory's (AFRL) Maui Optical Site to deploy a moderate field-of-view, 1.3 m aperture, optical telescope for orbital debris applications. The telescope will be located on the island of Legan in the Kwajalein Atoll and is scheduled for completion in the Spring of 2011. The telescope is intended to sample both low inclination/high eccentricity orbits and near geosynchronous orbits. The telescope will have a 1 deg diagonal field-of-view on a 4K x 4K CCD. The telescope is expected to be able to detect 10-cm diameter debris at geosynchronous altitudes (5 sec exposure assuming a spherical specular phase function w/ albedo =0.13). Once operational, the telescope has the potential of conducting simultaneous observations with radars operated by the US Army at Kwajalein Atoll (USAKA) and located on the island of Roi-Namur, approximately 55 km to the north of Legan. Four radars, representing 6 frequency bands, are available for use: ALTAIR (ARPA-Long Range Tracking and Instrumentation Radar) operating at VHF & UHF, TRADEX (Target Resolution and Discrimination Experiment) operating at L-band and S-band, ALCOR (ARPA-Lincoln C-band Observables Radar) operating at S-band, and MMW (Millimeter Wave) Radar operating at Ka-band. Also potentially available is the X-band GBRP (Ground Based Radar-Prototype located 25 km to the southeast of Legan on the main island of Kwajalein.

  11. Simulations of Aperture Synthesis Imaging Radar for the EISCAT_3D Project

    Science.gov (United States)

    La Hoz, C.; Belyey, V.

    2012-12-01

    EISCAT_3D is a project to build the next generation of incoherent scatter radars endowed with multiple 3-dimensional capabilities that will replace the current EISCAT radars in Northern Scandinavia. Aperture Synthesis Imaging Radar (ASIR) is one of the technologies adopted by the EISCAT_3D project to endow it with imaging capabilities in 3-dimensions that includes sub-beam resolution. Complemented by pulse compression, it will provide 3-dimensional images of certain types of incoherent scatter radar targets resolved to about 100 metres at 100 km range, depending on the signal-to-noise ratio. This ability will open new research opportunities to map small structures associated with non-homogeneous, unstable processes such as aurora, summer and winter polar radar echoes (PMSE and PMWE), Natural Enhanced Ion Acoustic Lines (NEIALs), structures excited by HF ionospheric heating, meteors, space debris, and others. To demonstrate the feasibility of the antenna configurations and the imaging inversion algorithms a simulation of synthetic incoherent scattering data has been performed. The simulation algorithm incorporates the ability to control the background plasma parameters with non-homogeneous, non-stationary components over an extended 3-dimensional space. Control over the positions of a number of separated receiving antennas, their signal-to-noise-ratios and arriving phases allows realistic simulation of a multi-baseline interferometric imaging radar system. The resulting simulated data is fed into various inversion algorithms. This simulation package is a powerful tool to evaluate various antenna configurations and inversion algorithms. Results applied to realistic design alternatives of EISCAT_3D will be described.

  12. Multi-function radar emitter identification based on stochastic syntax-directed translation schema

    OpenAIRE

    Liu, Haijun; Yu, Hongqi; Sun, Zhaolin; Diao, Jietao

    2014-01-01

    To cope with the problem of emitter identification caused by the radar words’ uncertainty of measured multi-function radar emitters, this paper proposes a new identification method based on stochastic syntax-directed translation schema (SSDTS). This method, which is deduced from the syntactic modeling of multi-function radars, considers the probabilities of radar phrases appearance in different radar modes as well as the probabilities of radar word errors occurrence in different radar phrases...

  13. Simultaneous Radar and Satellite Data Storm-Scale Assimilation Using an Ensemble Kalman Filter Approach for 24 May 2011

    Science.gov (United States)

    Jones, Thomas A.; Stensrud, David; Wicker, Louis; Minnis, Patrick; Palikonda, Rabindra

    2015-01-01

    Assimilating high-resolution radar reflectivity and radial velocity into convection-permitting numerical weather prediction models has proven to be an important tool for improving forecast skill of convection. The use of satellite data for the application is much less well understood, only recently receiving significant attention. Since both radar and satellite data provide independent information, combing these two sources of data in a robust manner potentially represents the future of high-resolution data assimilation. This research combines Geostationary Operational Environmental Satellite 13 (GOES-13) cloud water path (CWP) retrievals with Weather Surveillance Radar-1988 Doppler (WSR-88D) reflectivity and radial velocity to examine the impacts of assimilating each for a severe weather event occurring in Oklahoma on 24 May 2011. Data are assimilated into a 3-km model using an ensemble adjustment Kalman filter approach with 36 members over a 2-h assimilation window between 1800 and 2000 UTC. Forecasts are then generated for 90 min at 5-min intervals starting at 1930 and 2000 UTC. Results show that both satellite and radar data are able to initiate convection, but that assimilating both spins up a storm much faster. Assimilating CWP also performs well at suppressing spurious precipitation and cloud cover in the model as well as capturing the anvil characteristics of developed storms. Radar data are most effective at resolving the 3D characteristics of the core convection. Assimilating both satellite and radar data generally resulted in the best model analysis and most skillful forecast for this event.

  14. Ranger© - An Affordable, Advanced, Next-Generation, Dual-Pol, X-Band Weather Radar

    Science.gov (United States)

    Stedronsky, Richard

    2014-05-01

    The Enterprise Electronics Corporation (EEC) Ranger© system is a new generation, X-band (3 cm), Adaptive Polarization Doppler Weather Surveillance Radar that fills the gap between high-cost, high-power traditional radar systems and the passive ground station weather sensors. Developed in partnership with the University of Oklahoma Advanced Radar Research Center (ARRC), the system uses relatively low power solid-state transmitters and pulse compression technology to attain nearly the same performance capabilities of much more expensive traditional radar systems. The Ranger© also employs Adaptive Dual Polarization (ADP) techniques to allow Alternating or Simultaneous Dual Polarization capability with total control over the transmission polarization state using dual independent coherent transmitters. Ranger© has been designed using the very latest technology available in the industry and the technical and manufacturing experience gained through over four decades of successful radar system design and production at EEC. The entire Ranger© design concept emphasizes precision, stability, reliability, and value using proven solid state technology combined with the most advanced motion control system ever conceived for weather radar. Key applications include meteorology, hydrology, aviation, offshore oil/gas drilling, wind energy, and outdoor event situational awareness.

  15. Space Radar Image of Kilauea Volcano, Hawaii

    Science.gov (United States)

    1994-01-01

    This is a deformation map of the south flank of Kilauea volcano on the big island of Hawaii, centered at 19.5 degrees north latitude and 155.25 degrees west longitude. The map was created by combining interferometric radar data -- that is data acquired on different passes of the space shuttle which are then overlayed to obtain elevation information -- acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar during its first flight in April 1994 and its second flight in October 1994. The area shown is approximately 40 kilometers by 80 kilometers (25 miles by 50 miles). North is toward the upper left of the image. The colors indicate the displacement of the surface in the direction that the radar instrument was pointed (toward the right of the image) in the six months between images. The analysis of ground movement is preliminary, but appears consistent with the motions detected by the Global Positioning System ground receivers that have been used over the past five years. The south flank of the Kilauea volcano is among the most rapidly deforming terrains on Earth. Several regions show motions over the six-month time period. Most obvious is at the base of Hilina Pali, where 10 centimeters (4 inches) or more of crustal deformation can be seen in a concentrated area near the coastline. On a more localized scale, the currently active Pu'u O'o summit also shows about 10 centimeters (4 inches) of change near the vent area. Finally, there are indications of additional movement along the upper southwest rift zone, just below the Kilauea caldera in the image. Deformation of the south flank is believed to be the result of movements along faults deep beneath the surface of the volcano, as well as injections of magma, or molten rock, into the volcano's 'plumbing' system. Detection of ground motions from space has proven to be a unique capability of imaging radar technology. Scientists hope to use deformation data acquired by SIR-C/X-SAR and future imaging

  16. New formulation for interferometric synthetic aperture radar for terrain mapping

    Science.gov (United States)

    Jakowatz, Charles V., Jr.; Wahl, Daniel E.; Eichel, Paul H.; Thompson, Paul A.

    1994-06-01

    The subject of interferometric synthetic aperture radar (IFSAR) for high-accuracy terrain elevation mapping continues to gain importance in the arena of radar signal processing. Applications to problems in precision terrain-aided guidance and automatic target recognition, as well as a variety of civil applications, are being studied by a number of researchers. Not unlike many other areas of SAR processing, the subject of IFSAR can, at first glance, appear to be somewhat mysterious. In this paper we show how the mathematics of IFSAR for terrain elevation mapping using a pair of spotlight mode SAR collections can be derived in a very straightforward manner. Here, we employ an approach that relies entirely on Fourier transforms, and utilizes no reference to range equations or Doppler concepts. The result is a simplified explanation of the fundamentals of interferometry, including an easily-seen link between image domain phase difference and terrain elevation height. The derivation builds upon previous work by the authors in which a framework for spotlight mode SAR image formation based on an analogy to 3D computerized axial tomography (CAT) was developed. After outlining the major steps in the mathematics, we show how a computer simulator which utilizes 3D Fourier transforms can be constructed that demonstrates all of the major aspects of IFSAR from spotlight mode collections.

  17. Bridge Testing With Ground-Based Interferometric Radar: Experimental Results

    International Nuclear Information System (INIS)

    Chiara, P.; Morelli, A.

    2010-01-01

    The research of innovative non-contact techniques aimed at the vibration measurement of civil engineering structures (also for damage detection and structural health monitoring) is continuously directed to the optimization of measures and methods. Ground-Based Radar Interferometry (GBRI) represents the more recent technique available for static and dynamic control of structures and ground movements.Dynamic testing of bridges and buildings in operational conditions are currently performed: (a) to assess the conformity of the structure to the project design at the end of construction; (b) to identify the modal parameters (i.e. natural frequencies, mode shapes and damping ratios) and to check the variation of any modal parameters over the years; (c) to evaluate the amplitude of the structural response to special load conditions (i.e. strong winds, earthquakes, heavy railway or roadway loads). If such tests are carried out by using a non-contact technique (like GBRI), the classical issues of contact sensors (like accelerometers) are easily overtaken.This paper presents and discusses the results of various tests carried out on full-scale bridges by using a Stepped Frequency-Continuous Wave radar system.

  18. Bridge Testing With Ground-Based Interferometric Radar: Experimental Results

    Science.gov (United States)

    Chiara, P.; Morelli, A.

    2010-05-01

    The research of innovative non-contact techniques aimed at the vibration measurement of civil engineering structures (also for damage detection and structural health monitoring) is continuously directed to the optimization of measures and methods. Ground-Based Radar Interferometry (GBRI) represents the more recent technique available for static and dynamic control of structures and ground movements. Dynamic testing of bridges and buildings in operational conditions are currently performed: (a) to assess the conformity of the structure to the project design at the end of construction; (b) to identify the modal parameters (i.e. natural frequencies, mode shapes and damping ratios) and to check the variation of any modal parameters over the years; (c) to evaluate the amplitude of the structural response to special load conditions (i.e. strong winds, earthquakes, heavy railway or roadway loads). If such tests are carried out by using a non-contact technique (like GBRI), the classical issues of contact sensors (like accelerometers) are easily overtaken. This paper presents and discusses the results of various tests carried out on full-scale bridges by using a Stepped Frequency-Continuous Wave radar system.

  19. Quad channel software defined receiver for passive radar application

    Directory of Open Access Journals (Sweden)

    Pető Tamás

    2017-03-01

    Full Text Available In recent times the growing utilization of the electromagnetic environment brings the passive radar researches more and more to the fore. For the utilization of the wide range of illuminators of opportunity the application of wideband radio receivers is required. At the same time the multichannel receiver structure has also critical importance in target direction finding and interference suppression. This paper presents the development of a multichannel software defined receiver specifically for passive radar applications. One of the relevant feature of the developed receiver platform is its up-to-date SoC (System on hip based structure, which greatly enhance the integration and signal processing capacity of the system, all while keeping the costs low. The software defined operation of the discussed receiver system is demonstrated with using DVB-T (Digital Video Broadcast – Terrestrial signal as illuminator of opportunity. During this demonstration the multichannel capabilities of the realized system are also tested with real data using direction finding and beamforming algorithms.

  20. Three-dimensional subsurface imaging synthetic aperture radar

    International Nuclear Information System (INIS)

    Moussally, G.J.

    1995-01-01

    The objective of this applied research and development project is to develop a system known as '3-D SISAR'. This system consists of a ground penetrating radar with software algorithms designed for the detection, location, and identification of buried objects in the underground hazardous waste environments found at DOE storage sites. Three-dimensional maps of the object locations will be produced which can assist the development of remediation strategies and the characterization of the digface during remediation operations. It is expected that the 3-D SISAR will also prove useful for monitoring hydrocarbon based contaminant migration after remediation. The underground imaging technique being developed under this contract utilizes a spotlight mode Synthetic Aperture Radar (SAR) approach which, due to its inherent stand-off capability, will permit the rapid survey of a site and achieve a high degree of productivity over large areas. When deployed from an airborne platform, the stand-off techniques is also seen as a way to overcome practical survey limitations encountered at vegetated sites

  1. Reconstruction of the sea surface elevation from the analysis of the data collected by a wave radar system

    Science.gov (United States)

    Ludeno, Giovanni; Soldovieri, Francesco; Serafino, Francesco; Lugni, Claudio; Fucile, Fabio; Bulian, Gabriele

    2016-04-01

    X-band radar system is able to provide information about direction and intensity of the sea surface currents and dominant waves in a range of few kilometers from the observation point (up to 3 nautical miles). This capability, together with their flexibility and low cost, makes these devices useful tools for the sea monitoring either coastal or off-shore area. The data collected from wave radar system can be analyzed by using the inversion strategy presented in [1,2] to obtain the estimation of the following sea parameters: peak wave direction; peak period; peak wavelength; significant wave height; sea surface current and bathymetry. The estimation of the significant wave height represents a limitation of the wave radar system because of the radar backscatter is not directly related to the sea surface elevation. In fact, in the last period, substantial research has been carried out to estimate significant wave height from radar images either with or without calibration using in-situ measurements. In this work, we will present two alternative approaches for the reconstruction of the sea surface elevation from wave radar images. In particular, the first approach is based on the basis of an approximated version of the modulation transfer function (MTF) tuned from a series of numerical simulation, following the line of[3]. The second approach is based on the inversion of radar images using a direct regularised least square technique. Assuming a linearised model for the tilt modulation, the sea elevation has been reconstructed as a least square fitting of the radar imaging data[4]. References [1]F. Serafino, C. Lugni, and F. Soldovieri, "A novel strategy for the surface current determination from marine X-band radar data," IEEE Geosci.Remote Sens. Lett., vol. 7, no. 2, pp. 231-235, Apr. 2010. [2]Ludeno, G., Brandini, C., Lugni, C., Arturi, D., Natale, A., Soldovieri, F., Serafino, F. (2014). Remocean System for the Detection of the Reflected Waves from the Costa

  2. Development of wide band digital receiver for atmospheric radars using COTS board based SDR

    Science.gov (United States)

    Yasodha, Polisetti; Jayaraman, Achuthan; Thriveni, A.

    2016-07-01

    Digital receiver extracts the received echo signal information, and is a potential subsystem for atmospheric radar, also referred to as wind profiling radar (WPR), which provides the vertical profiles of 3-dimensional wind vector in the atmosphere. This paper presents the development of digital receiver using COTS board based Software Defined Radio technique, which can be used for atmospheric radars. The developmental work is being carried out at National Atmospheric Research Laboratory (NARL), Gadanki. The digital receiver consists of a commercially available software defined radio (SDR) board called as universal software radio peripheral B210 (USRP B210) and a personal computer. USRP B210 operates over a wider frequency range from 70 MHz to 6 GHz and hence can be used for variety of radars like Doppler weather radars operating in S/C bands, in addition to wind profiling radars operating in VHF, UHF and L bands. Due to the flexibility and re-configurability of SDR, where the component functionalities are implemented in software, it is easy to modify the software to receive the echoes and process them as per the requirement suitable for the type of the radar intended. Hence, USRP B210 board along with the computer forms a versatile digital receiver from 70 MHz to 6 GHz. It has an inbuilt direct conversion transceiver with two transmit and two receive channels, which can be operated in fully coherent 2x2 MIMO fashion and thus it can be used as a two channel receiver. Multiple USRP B210 boards can be synchronized using the pulse per second (PPS) input provided on the board, to configure multi-channel digital receiver system. RF gain of the transceiver can be varied from 0 to 70 dB. The board can be controlled from the computer via USB 3.0 interface through USRP hardware driver (UHD), which is an open source cross platform driver. The USRP B210 board is connected to the personal computer through USB 3.0. Reference (10 MHz) clock signal from the radar master oscillator

  3. Airborne Radar Observations of Severe Hailstorms: Implications for Future Spaceborne Radar

    Science.gov (United States)

    Heymsfield, Gerald M.; Tian, Lin; Li, Lihua; McLinden, Matthew; Cervantes, Jaime I.

    2013-01-01

    A new dual-frequency (Ku and Ka band) nadir-pointing Doppler radar on the high-altitude NASA ER-2 aircraft, called the High-Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP), has collected data over severe thunderstorms in Oklahoma and Kansas during the Midlatitude Continental Convective Clouds Experiment (MC3E). The overarching motivation for this study is to understand the behavior of the dualwavelength airborne radar measurements in a global variety of thunderstorms and how these may relate to future spaceborne-radar measurements. HIWRAP is operated at frequencies that are similar to those of the precipitation radar on the Tropical Rainfall Measuring Mission (Ku band) and the upcoming Global Precipitation Measurement mission satellite's dual-frequency (Ku and Ka bands) precipitation radar. The aircraft measurements of strong hailstorms have been combined with ground-based polarimetric measurements to obtain a better understanding of the response of the Ku- and Ka-band radar to the vertical distribution of the hydrometeors, including hail. Data from two flight lines on 24 May 2011 are presented. Doppler velocities were approx. 39m/s2at 10.7-km altitude from the first flight line early on 24 May, and the lower value of approx. 25m/s on a second flight line later in the day. Vertical motions estimated using a fall speed estimate for large graupel and hail suggested that the first storm had an updraft that possibly exceeded 60m/s for the more intense part of the storm. This large updraft speed along with reports of 5-cm hail at the surface, reflectivities reaching 70 dBZ at S band in the storm cores, and hail signals from polarimetric data provide a highly challenging situation for spaceborne-radar measurements in intense convective systems. The Ku- and Ka-band reflectivities rarely exceed approx. 47 and approx. 37 dBZ, respectively, in these storms.

  4. Space radar image of Mauna Loa, Hawaii

    Science.gov (United States)

    1995-01-01

    This image of the Mauna Loa volcano on the Big Island of Hawaii shows the capability of imaging radar to map lava flows and other volcanic structures. Mauna Loa has erupted more than 35 times since the island was first visited by westerners in the early 1800s. The large summit crater, called Mokuaweoweo Caldera, is clearly visible near the center of the image. Leading away from the caldera (towards top right and lower center) are the two main rift zones shown here in orange. Rift zones are areas of weakness within the upper part of the volcano that are often ripped open as new magma (molten rock) approaches the surface at the start of an eruption. The most recent eruption of Mauna Loa was in March and April 1984, when segments of the northeast rift zones were active. If the height of the volcano was measured from its base on the ocean floor instead of from sea level, Mauna Loa would be the tallest mountain on Earth. Its peak (center of the image) rises more than 8 kilometers (5 miles) above the ocean floor. The South Kona District, known for cultivation of macadamia nuts and coffee, can be seen in the lower left as white and blue areas along the coast. North is toward the upper left. The area shown is 41.5 by 75 kilometers (25.7 by 46.5 miles), centered at 19.5 degrees north latitude and 155.6 degrees west longitude. The image was acquired by the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/ X-SAR) aboard the space shuttle Endeavour on its 36th orbit on October 2, 1994. The radar illumination is from the left of the image. The colors in this image were obtained using the following radar channels: red represents the L-band (horizontally transmitted and received); green represents the L-band (horizontally transmitted, vertically received); blue represents the C-band (horizontally transmitted, vertically received). The resulting color combinations in this radar image are caused by differences in surface roughness of the lava flows. Smoother flows

  5. Quantification of Reflection Patterns in Ground-Penetrating Radar Data

    Science.gov (United States)

    Moysey, S.; Knight, R. J.; Jol, H. M.; Allen-King, R. M.; Gaylord, D. R.

    2005-12-01

    Radar facies analysis provides a way of interpreting the large-scale structure of the subsurface from ground-penetrating radar (GPR) data. Radar facies are often distinguished from each other by the presence of patterns, such as flat-lying, dipping, or chaotic reflections, in different regions of a radar image. When these patterns can be associated with radar facies in a repeated and predictable manner we refer to them as `radar textures'. While it is often possible to qualitatively differentiate between radar textures visually, pattern recognition tools, like neural networks, require a quantitative measure to discriminate between them. We investigate whether currently available tools, such as instantaneous attributes or metrics adapted from standard texture analysis techniques, can be used to improve the classification of radar facies. To this end, we use a neural network to perform cross-validation tests that assess the efficacy of different textural measures for classifying radar facies in GPR data collected from the William River delta, Saskatchewan, Canada. We found that the highest classification accuracies (>93%) were obtained for measures of texture that preserve information about the spatial arrangement of reflections in the radar image, e.g., spatial covariance. Lower accuracy (87%) was obtained for classifications based directly on windows of amplitude data extracted from the radar image. Measures that did not account for the spatial arrangement of reflections in the image, e.g., instantaneous attributes and amplitude variance, yielded classification accuracies of less than 65%. Optimal classifications were obtained for textural measures that extracted sufficient information from the radar data to discriminate between radar facies but were insensitive to other facies specific characteristics. For example, the rotationally invariant Fourier-Mellin transform delivered better classification results than the spatial covariance because dip angle of the

  6. HF Radar Sea-echo from Shallow Water

    Directory of Open Access Journals (Sweden)

    Josh Kohut

    2008-08-01

    Full Text Available HF radar systems are widely and routinely used for the measurement of ocean surface currents and waves. Analysis methods presently in use are based on the assumption of infinite water depth, and may therefore be inadequate close to shore where the radar echo is strongest. In this paper, we treat the situation when the radar echo is returned from ocean waves that interact with the ocean floor. Simulations are described which demonstrate the effect of shallow water on radar sea-echo. These are used to investigate limits on the existing theory and to define water depths at which shallow-water effects become significant. The second-order spectral energy increases relative to the first-order as the water depth decreases, resulting in spectral saturation when the waveheight exceeds a limit defined by the radar transmit frequency. This effect is particularly marked for lower radar transmit frequencies. The saturation limit on waveheight is less for shallow water. Shallow water affects second-order spectra (which gives wave information far more than first-order (which gives information on current velocities, the latter being significantly affected only for the lowest radar transmit frequencies for extremely shallow water. We describe analysis of radar echo from shallow water measured by a Rutgers University HF radar system to give ocean wave spectral estimates. Radar-derived wave height, period and direction are compared with simultaneous shallow-water in-situ measurements.

  7. A Dual-Wavelength Radar Technique to Detect Hydrometeor Phases

    Science.gov (United States)

    Liao, Liang; Meneghini, Robert

    2016-01-01

    This study is aimed at investigating the feasibility of a Ku- and Ka-band space/air-borne dual wavelength radar algorithm to discriminate various phase states of precipitating hydrometeors. A phase-state classification algorithm has been developed from the radar measurements of snow, mixed-phase and rain obtained from stratiform storms. The algorithm, presented in the form of the look-up table that links the Ku-band radar reflectivities and dual-frequency ratio (DFR) to the phase states of hydrometeors, is checked by applying it to the measurements of the Jet Propulsion Laboratory, California Institute of Technology, Airborne Precipitation Radar Second Generation (APR-2). In creating the statistically-based phase look-up table, the attenuation corrected (or true) radar reflectivity factors are employed, leading to better accuracy in determining the hydrometeor phase. In practice, however, the true radar reflectivities are not always available before the phase states of the hydrometeors are determined. Therefore, it is desirable to make use of the measured radar reflectivities in classifying the phase states. To do this, a phase-identification procedure is proposed that uses only measured radar reflectivities. The procedure is then tested using APR-2 airborne radar data. Analysis of the classification results in stratiform rain indicates that the regions of snow, mixed-phase and rain derived from the phase-identification algorithm coincide reasonably well with those determined from the measured radar reflectivities and linear depolarization ratio (LDR).

  8. Sensor management in RADAR/IRST track fusion

    Science.gov (United States)

    Hu, Shi-qiang; Jing, Zhong-liang

    2004-07-01

    In this paper, a novel radar management strategy technique suitable for RADAR/IRST track fusion, which is based on Fisher Information Matrix (FIM) and fuzzy stochastic decision approach, is put forward. Firstly, optimal radar measurements' scheduling is obtained by the method of maximizing determinant of the Fisher information matrix of radar and IRST measurements, which is managed by the expert system. Then, suggested a "pseudo sensor" to predict the possible target position using the polynomial method based on the radar and IRST measurements, using "pseudo sensor" model to estimate the target position even if the radar is turned off. At last, based on the tracking performance and the state of target maneuver, fuzzy stochastic decision is used to adjust the optimal radar scheduling and retrieve the module parameter of "pseudo sensor". The experiment result indicates that the algorithm can not only limit Radar activity effectively but also keep the tracking accuracy of active/passive system well. And this algorithm eliminates the drawback of traditional Radar management methods that the Radar activity is fixed and not easy to control and protect.

  9. wradlib - an Open Source Library for Weather Radar Data Processing

    Science.gov (United States)

    Pfaff, Thomas; Heistermann, Maik; Jacobi, Stephan

    2014-05-01

    Even though weather radar holds great promise for the hydrological sciences, offering precipitation estimates with unrivaled spatial and temporal resolution, there are still problems impeding its widespread use, among which are: almost every radar data set comes with a different data format with public reading software being available only rarely. standard products as issued by the meteorological services often do not serve the needs of original research, having either too many or too few corrections applied. Especially when new correction methods are to be developed, researchers are often forced to start from scratch having to implement many corrections in addition to those they are actually interested in. many algorithms published in the literature cannot be recreated using the corresponding article only. Public codes, providing insight into the actual implementation and how an approach deals with possible exceptions are rare. the radial scanning setup of weather radar measurements produces additional challenges, when it comes to visualization or georeferencing of this type of data. Based on these experiences, and in the hope to spare others at least some of these tedious tasks, wradlib offers the results of the author's own efforts and a growing number of community-supplied methods. wradlib is designed as a Python library of functions and classes to assist users in their analysis of weather radar data. It provides solutions for all tasks along a typical processing chain leading from raw reflectivity data to corrected, georeferenced and possibly gauge adjusted quantitative precipitation estimates. There are modules for data input/output, data transformation including Z/R transformation, clutter identification, attenuation correction, dual polarization and differential phase processing, interpolation, georeferencing, compositing, gauge adjustment, verification and visualization. The interpreted nature of the Python programming language makes wradlib an ideal tool

  10. Crosshole investigations - results from borehole radar investigations

    International Nuclear Information System (INIS)

    Olsson, O.; Falk, L.; Sandberg, E.; Forslund, O.; Lundmark, L.

    1987-05-01

    A new borehole radar system has been designed, built and tested. The system consists of borehole transmitter and receiver probes, a signal control unit for communication with the borehole probes, and a computer unit for storage and display of data. The system can be used both in singlehole and crosshole modes and probing ranges of 115 m and 300 m, respectively, have been obtained at Stripa. The borehole radar is a short pulse system which uses center frequencies in the range 20 to 60 MHz. Single hole reflection measurements have been used to identify fracture zones and to determine their position and orientation. The travel time and amplitude of the first arrival measured in a crosshole experiment can be used as input data in a tomographic analysis. (orig./DG)

  11. Venus: radar determination of gravity potential.

    Science.gov (United States)

    Shapiro, I I; Pettengill, G H; Sherman, G N; Rogers, A E; Ingalls, R P

    1973-02-02

    We describe a method for the determination of the gravity potential of Venus from multiple-frequency radar measurements. The method is based on the strong frequency dependence of the absorption of radio waves in Venus' atmosphere. Comparison of the differing radar reflection intensities at several frequencies yields the height of the surface relative to a reference pressure contour; combination with measurements of round-trip echo delays allows the pressure, and hence the gravity potential contour, to be mapped relative to the mean planet radius. Since calibration data from other frequencies are unavailable, the absorption-sensitive Haystack Observatory data have been analyzed under the assumption of uniform surface reflectivity to yield a gravity equipotential contour for the equatorial region and a tentative upper bound of 6 x 10(-4) on the fractional difference of Venus' principal equatorial moments of inertia. The minima in the equipotential contours appear to be associated with topographic minima.

  12. Feature Extraction in Radar Target Classification

    Directory of Open Access Journals (Sweden)

    Z. Kus

    1999-09-01

    Full Text Available This paper presents experimental results of extracting features in the Radar Target Classification process using the J frequency band pulse radar. The feature extraction is based on frequency analysis methods, the discrete-time Fourier Transform (DFT and Multiple Signal Characterisation (MUSIC, based on the detection of Doppler effect. The analysis has turned to the preference of DFT with implemented Hanning windowing function. We assumed to classify targets-vehicles into two classes, the wheeled vehicle and tracked vehicle. The results show that it is possible to classify them only while moving. The feature of the class results from a movement of moving parts of the vehicle. However, we have not found any feature to classify the wheeled and tracked vehicles while non-moving, although their engines are on.

  13. Research

    African Journals Online (AJOL)

    ebutamanya

    2015-03-02

    Mar 2, 2015 ... Joseph Daniels1,&, Ruth Nduati1,2, James Kiarie1,3, Carey Farquhar1,4,5 .... or basic science research career (Socio-Behavioral Research, .... a research environment that supports knowledge sharing to develop research ...

  14. Cassini radar: Instrument description and performance status

    Science.gov (United States)

    Johnson, W. T. K.; Im, E.; Borgarelli, L.; ZampoliniFaustini, E.

    1995-01-01

    The spacecraft of the Cassini mission is planned to be launched towards Saturn in October 1997. The mission is designed to study the physical structure and chemical composition of Titan. The results of the tests performed on the Cassini radar engineering qualification model (EQM) are summarized. The approach followed in the verification and evaluation of the performance of the radio frequency subsystem EQM is presented. The results show that the instrument satisfies the most relevant mission requirements.

  15. Forestry applications of ground-penetrating radar

    Energy Technology Data Exchange (ETDEWEB)

    Lorenzo, H.; Perez-Gracia, V.; Novo, A.; Armesto, J.

    2010-07-01

    Ground-penetrating radar (GPR) is a geophysical and close-range remote sensing technique based on the use of radar pulses to obtain cross-section images of underground features. This method is characterized by the transmission of an electromagnetic short length pulse (1-2 ns), presenting a centre frequency ranging from 10 MHz to 2.5 GHz. The principles of GPR operation are based on the ability of low frequency radar waves to penetrate into a non-conductive medium, usually subsoil, but also walls, concrete or wood. Those waves are detected after suffering a reflection in electromagnetic discontinuities of the propagation medium. Therefore, this is a suitable method to study changes in those physical properties, and also to characterize different mediums and the reflective targets providing information about their physical properties. The aim of this work is to describe and demonstrate different applications of GPR in forestry, showing the obtained results together with their interpretation. Firstly, in this paper, it is illustrated how GPR is able to map shallow bedrock, subsoil stratigraphy and also to estimate shallow water table depth. Secondly, different tree trunks as well as dry timber are analyzed, evaluating the different radar data obtained in each particular case, and observing differences in their electromagnetic properties related to the GPR response. Finally, several measurements were taken in order to analyze the use of GPR to detect tree root systems using polarimetric techniques, being possible to detect medium and big size roots, together with groups of small roots. (Author) 39 refs.

  16. High accuracy 3-D laser radar

    DEFF Research Database (Denmark)

    Busck, Jens; Heiselberg, Henning

    2004-01-01

    We have developed a mono-static staring 3-D laser radar based on gated viewing with range accuracy below 1 m at 10 m and 1 cm at 100. We use a high sensitivity, fast, intensified CCD camera, and a Nd:Yag passively Q-switched 32.4 kHz pulsed green laser at 532 nm. The CCD has 752x582 pixels. Camera...

  17. Artifacts in Radar Imaging of Moving Targets

    Science.gov (United States)

    2012-09-01

    CA, USA, 2007. [11] B. Borden, Radar imaging of airborne targets: A primer for Applied mathematicians and Physicists . New York, NY: Taylor and... Project (0704–0188) Washington DC 20503. 1. AGENCY USE ONLY (Leave blank) 2. REPORT DATE 21 September 2012 3. REPORT TYPE AND DATES COVERED...CW Continuous Wave DAC Digital to Analog Convertor DFT Discrete Fourier Transform FBP Filtered Back Projection FFT Fast Fourier Transform GPS

  18. CW Laser radar for combustion diagnostics

    Directory of Open Access Journals (Sweden)

    Malmqvist Elin

    2018-01-01

    Full Text Available A CW-laser radar system developed for combustion diagnostics is described. The system is based on triangulation to attain range information. A portable system has been constructed and here we show some result from measurements in various flames, for example Rayleigh scattering thermometry and monitoring of particle distributions with high temporal and spatial resolution. The concept can equally well be based on pulsed lasers, allowing suppression of background emission through gated detection.

  19. Radar for Measuring Soil Moisture Under Vegetation

    Science.gov (United States)

    Moghaddam, Mahta; Moller, Delwyn; Rodriguez, Ernesto; Rahmat-Samii, Yahya

    2004-01-01

    A two-frequency, polarimetric, spaceborne synthetic-aperture radar (SAR) system has been proposed for measuring the moisture content of soil as a function of depth, even in the presence of overlying vegetation. These measurements are needed because data on soil moisture under vegetation canopies are not available now and are necessary for completing mathematical models of global energy and water balance with major implications for global variations in weather and climate.

  20. Space Radar Image of Sydney, Australia

    Science.gov (United States)

    1994-01-01

    This spaceborne radar image is dominated by the metropolitan area of Australia's largest city, Sydney. Sydney Harbour, with numerous coves and inlets, is seen in the upper center of the image, and the roughly circular Botany Bay is shown in the lower right. The downtown business district of Sydney appears as a bright white area just above the center of the image. The Sydney Harbour Bridge is a white line adjacent to the downtown district. The well-known Sydney Opera House is the small, white dot to the right of the bridge. Urban areas appear yellow, blue and brown. The purple areas are undeveloped areas and park lands. Manly, the famous surfing beach, is shown in yellow at the top center of the image. Runways from the Sydney Airport are the dark features that extend into Botany Bay in the lower right. Botany Bay is the site where Captain James Cook first landed his ship, Endeavour, in 1770. The image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar (SIR-C/X-SAR) on April 20, 1994, onboard the space shuttle Endeavour. The area shown is 33 kilometers by 38kilometers (20 miles by 23 miles) and is centered at 33.9 degrees south latitude, 151.2 degrees east longitude. North is toward the upper left. The colors are assigned to different radar frequenciesand polarizations as follows: red is L-band, vertically transmittedand horizontally received; green is C-band, vertically transmitted and horizontally received; and blue is C-band, vertically transmittedand received. SIR-C/X-SAR, a joint mission of the German, Italianand United States space agencies, is part of NASA's Mission to Planet Earth. #####