Sample records for shuttle experimental radar

  1. Shuttle Radar Topographic Mission (SRTM) Illustration (United States)


    Launched February 11, 2000, the STS-99 Shuttle Radar Topographic Mission (SRTM) was the most ambitious Earth mapping mission to date. This illustration shows the Space Shuttle Endeavour orbiting some 145 miles (233 kilometers) above Earth. With C-band and X-band outboard anternae at work, one located in the Shuttle bay and the other located on the end of a 60-meter deployable mast, the SRTM radar was able to penetrate clouds as well as provide its own illumination, independent of daylight, obtaining 3-dimentional topographic images of the world's surface up to the Arctic and Antarctic Circles. The mission completed 222 hours of around the clock radar mapping, gathering enough information to fill more than 20,000 CDs.

  2. Shuttle imaging radar - Research sensor for earth resources observation (United States)

    Elachi, C.

    The operating characteristics of the Shuttle Imaging Radar (SIR) and intended experimentation to study the effects of the incidence angle, look direction, frequency, and polarization are described. SIR will be flown in 1984-1986, operate in the L- and C-bands, and have a look angle which can be varied through 15-75 deg. Polarizations of HH on the L-band and HH, VV, HV, and VH on the C-band are possible. The SIR will provide 10 and 30 m resolutions in the high and low resolution modes, respectively, with a swatch width between 35-125 km. Real-time to ground and on-board optical recording will be available, together with digital and optical processing. The antennas will be rotated in the Shuttle bay in 5 deg increments, permitting the formation of stereo pictures during several overpasses. Viewing at 1275 MHz is intended for imaging, while the 5300 MHz band can sense soil moisture

  3. Analysis of the accuracy of Shuttle Radar Topography Mission ...

    Indian Academy of Sciences (India)

    DTM; SRTM. Abstract. The Shuttle Radar Topography Mission (SRTM) carried out in February 2000 has provided near global topographic data that has been widely used in many fields of earth sciences. The mission goal of an absolute vertical ...

  4. Accuracy analysis of the 2014–2015 Global Shuttle Radar ...

    Indian Academy of Sciences (India)

    Global Shuttle Radar Topography Mission (SRTM) data products have been widely used in EarthSciences without an estimation of their accuracy and reliability even though large outliers exist in them.The global 1 arc-sec, 30 m resolution, SRTM C-Band (C-30) data collected in February 2000 has beenrecently released ...

  5. Analysis of the accuracy of Shuttle Radar Topography Mission (SRTM)

    Indian Academy of Sciences (India)

    Analysis of the accuracy of Shuttle Radar Topography. Mission (SRTM) height models using International Global. Navigation Satellite System Service (IGS) Network. Manas Mukul, Vinee Srivastava and Malay Mukul. J. Earth Syst. Sci. 124(6) cO Indian Academy of Sciences. Supplementary data ...

  6. Shuttle imaging radar A analysis of land use in Amazonia (United States)

    Stone, Thomas A.; Woodwell, George M.


    Over large areas in the tropics, satellite imagery is the principal source of data on the area, current stature, and extent of disturbance of the forests. The information from imagery that covers large areas at low resolution is greatly enhanced when different types of imagery can be compared. The paper presents a comparison of data from Landsat MSS and from the Shuttle Imaging Radar (SIR-A) L band HH polarization data for sites in the Amazon Basin. Results indicate that SIR-A backscatter from the undisturbed forest was lower than that from some disturbed areas and from flooded forests and that SIR-A brightness, increases nonlinearly with the Landsat normalized difference vegetation index. It is hypothesized that the brightest radar returns in southern Amazonia are from newly cleared forests that are littered with standing and fallen tree boles that function as corner reflectors; and that backscatter will diminish from disturbed areas over time as fields are burned repeatedly.

  7. Shuttle Imaging Radar-C mission operations - Technology test bed for Earth Observing System synthetic aperture radar (United States)

    Trimble, J. P.; Collins, C. E.


    The mission operations for the Space Radar Lab (SRL), particularly in the areas of real-time replanning and science activity coordination, are presented. The two main components of SRL are the Shuttle Imaging Radar-C and the X-Band Synthetic Aperture Radar. The Earth Observing System SAR will be a multispectral, multipolarization radar satellite that will provide information over an entire decade, permitting scientists to monitor large-scale changes in the earth's environment over a long period of time.

  8. Ku band - The first year of operation. [Shuttle Orbiter integrated communication and radar system (United States)

    Griffin, J. W.; Haddad, H.; Magnusson, H. G.; Mohler, C. L.


    The Space Shuttle Orbiter's Ku-band integrated radar and communications system furnishes the preferred link through the Tracking and Data Relay Satellite (TRDS), providing rendezvous radar function. During the first year of operations, communications through TRDS provided a channel for the 48 Mbps data from Spacelab. Attention is presently given to the most significant activities of the radar during its initial year.

  9. Radar transponder antenna pattern analysis for the space shuttle (United States)

    Radcliff, Roger


    In order to improve tracking capability, radar transponder antennas will soon be mounted on the Shuttle solid rocket boosters (SRB). These four antennas, each being identical cavity-backed helices operating at 5.765 GHz, will be mounted near the top of the SRB's, adjacent to the intertank portion of the external tank. The purpose is to calculate the roll-plane pattern (the plane perpendicular to the SRB axes and containing the antennas) in the presence of this complex electromagnetic environment. The large electrical size of this problem mandates an optical (asymptotic) approach. Development of a specific code for this application is beyond the scope of a summer fellowship; thus a general purpose code, the Numerical Electromagnetics Code - Basic Scattering Code, was chosen as the computational tool. This code is based on the modern Geometrical Theory of Diffraction, and allows computation of scattering of bodies composed of canonical problems such as plates and elliptic cylinders. Apertures mounted on a curved surface (the SRB) cannot be accomplished by the code, so an antenna model consisting of wires excited by a method of moments current input was devised that approximated the actual performance of the antennas. The improvised antenna model matched well with measurements taken at the MSFC range. The SRB's, the external tank, and the shuttle nose were modeled as circular cylinders, and the code was able to produce what is thought to be a reasonable roll-plane pattern.

  10. The role of space borne imaging radars in environmental monitoring: Some shuttle imaging radar results in Asia (United States)

    Imhoff, Marc L.; Vermillion, C. H.


    The synoptic view afforded by orbiting Earth sensors can be extremely valuable for resource evaluation, environmental monitoring and development planning. For many regions of the world, however, cloud cover has prevented the acquisition of remotely sensed data during the most environmentally stressful periods of the year. How synthetic aperture imaging radar can be used to provide valuable data about the condition of the Earth's surface during periods of bad weather is discussed. Examples are given of applications using data from the Shuttle Imaging Radars (SIR) A and B for agricultural land use and crop condition assessment, monsoon flood boundary and flood damage assessment, water resource monitoring and terrain modeling, coastal forest mapping and vegetation penetration, and coastal development monitoring. Recent SIR-B results in Bangladesh are emphasized, radar system basics are reviewed and future SAR systems are discussed.

  11. Shuttle Radar Topography Mission (SRTM) Flight System Design and Operations Overview (United States)

    Shen, Yuhsyen; Shaffer, Scott J.; Jordan, Rolando L.


    This paper provides an overview of the Shuttle Radar Topography Mission (SRTM), with emphasis on flight system implementation and mission operations from systems engineering perspective. Successfully flown in February, 2000, the SRTM's primary payload consists of several subsystems to form the first spaceborne dual-frequency (C-band and X-band) fixed baseline interferometric synthetic aperture radar (InSAR) system, with the mission objective to acquire data sets over 80% of Earth's landmass for height reconstruction. The paper provides system architecture, unique design features, engineering budgets, design verification, in-flight checkout and data acquisition of the SRTM payload, in particular for the C-band system. Mission operation and post-mission data processing activities are also presented. The complexity of the SRTM as a system, the ambitious mission objective, the demanding requirements and the high interdependency between multi-disciplined subsystems posed many challenges. The engineering experience and the insight thus gained have important implications for future spaceborne interferometric SAR mission design and implementation.

  12. Comparison of Shuttle Imaging Radar-B ocean wave image spectra with linear model predictions based on aircraft measurements (United States)

    Monaldo, Frank M.; Lyzenga, David R.


    During October 1984, coincident Shuttle Imaging Radar-B synthetic aperture radar (SAR) imagery and wave measurements from airborne instrumentation were acquired. The two-dimensional wave spectrum was measured by both a radar ocean-wave spectrometer and a surface-contour radar aboard the aircraft. In this paper, two-dimensional SAR image intensity variance spectra are compared with these independent measures of ocean wave spectra to verify previously proposed models of the relationship between such SAR image spectra and ocean wave spectra. The results illustrate both the functional relationship between SAR image spectra and ocean wave spectra and the limitations imposed on the imaging of short-wavelength, azimuth-traveling waves.

  13. Space Shuttle Exhaust Modifications of the Mid-Latitude Ionospheric Plasma As Diagnosed By Ground Based Radar (United States)

    Lind, F. D.; Erickson, P. J.; Bhatt, A.; Bernhardt, P. A.


    The Space Shuttle's Orbital Maneuvering System (OMS) engines have been used since the early days of the STS program for active ionospheric modification experiments designed to be viewed by ground based ionospheric radar systems. In 1995, the Naval Research Laboratory initiated the Shuttle Ionospheric Modification with Pulsed Localized Exhaust (SIMPLEX) Program using dedicated Space Shuttle OMS burns scheduled through the US Department of Defense's Space Test Program. SIMPLEX objectives include generation of localized ion-acoustic turbulence and the formation of ionospheric density irregularities for injections perpendicular to the local magnetic field, creating structures which can scatter incident UHF radar signals. We discuss radar observations made during several recent SIMPLEX mid-latitude experiments conducted over the Millstone Hill incoherent scatter radar system in Westford, Massachusetts. OMS engine firings release 10 kg/s of CO2, H2, H2O, and N2 molecules which charge exchange with ambient O+ ions in the F region, producing molecular ions and long lived electron density depletions as recombination occurs with ambient electrons. Depending on the magnetic field angle, the high velocity of the injected reactive exhaust molecules relative to the background ionosphere can create longitudinal propagating ion acoustic waves with amplitudes well above normal thermal levels and stimulate a wide variety of plasma instability processes. These effects produce high radar cross section targets readily visible to the Millstone Hill system, a high power large aperture radar designed to measure very weak scatter from the quiescent background ionosphere. We will survey the plasma instability parameter space explored to date and discuss plans for future SIMPLEX observations.

  14. Experimental Investigations of Space Shuttle BX-265 Foam (United States)

    Lerch, Bradley A.; Sullivan, Roy M.


    This report presents a variety of experimental studies on the polyurethane foam, BX-265. This foam is used as a close-out foam insulation on the space shuttle external tank. The purpose of this work is to provide a better understanding of the foam s behavior and to support advanced modeling efforts. The following experiments were performed: Thermal expansion was measured for various heating rates. The in situ expansion of foam cells was documented by heating the foam in a scanning electron microscope. Expansion mechanisms are described. Thermogravimetric analysis was performed at various heating rates and for various environments. The glass transition temperature was also measured. The effects of moisture on the foam were studied. Time-dependent effects were measured to give preliminary data on viscoelastoplastic properties.

  15. Uncertainties in the Shuttle Radar Topography Mission (SRTM) Heights: Insights from the Indian Himalaya and Peninsula. (United States)

    Mukul, Manas; Srivastava, Vinee; Jade, Sridevi; Mukul, Malay


    The Shuttle Radar Topography Mission (SRTM) Digital Terrain Elevation Data (DTED) are used with the consensus view that it has a minimum vertical accuracy of 16 m absolute error at 90% confidence (Root Mean Square Error (RMSE) of 9.73 m) world-wide. However, vertical accuracy of the data decreases with increase in slope and elevation due to presence of large outliers and voids. Therefore, studies using SRTM data "as is", especially in regions like the Himalaya, are not statistically meaningful. New data from ~200 high-precision static Global Position System (GPS) Independent Check Points (ICPs) in the Himalaya and Peninsular India indicate that only 1-arc X-Band data are usable "as is" in the Himalaya as it has height accuracy of 9.18 m (RMSE). In contrast, recently released (2014-2015) "as-is" 1-arc and widely used 3-arc C-Band data have a height accuracy of RMSE 23.53 m and 47.24 m and need to be corrected before use. Outlier and void filtering improves the height accuracy to RMSE 8 m, 10.14 m, 14.38 m for 1-arc X and C-Band and 3-arc C-Band data respectively. Our study indicates that the C-Band 90 m and 30 m DEMs are well-aligned and without any significant horizontal offset implying that area and length computations using both the datasets have identical values.

  16. NASADEM Overview and First Results: Shuttle Radar Topography Mission (SRTM) Reprocessing and Improvements (United States)

    Buckley, S.; Agram, P. S.; Belz, J. E.; Crippen, R. E.; Gurrola, E. M.; Hensley, S.; Kobrick, M.; Lavalle, M.; Martin, J. M.; Neumann, M.; Nguyen, Q.; Rosen, P. A.; Shimada, J.; Simard, M.; Tung, W.


    NASADEM is a significant modernization of SRTM digital elevation model (DEM) data supported by the NASA MEaSUREs program. We are reprocessing the raw radar signal data using improved algorithms and incorporating ICESat and ASTER-derived DEM data unavailable during the original processing. The NASADEM products will be freely-available through the Land Processes Distributed Active Archive Center (LPDAAC) at 1-arcsecond spacing. The most significant processing improvements involve void reduction through improved phase unwrapping and using ICESat data for control. The updated unwrapping strategy now includes the use of SNAPHU for data processing patches where the unwrapped coverage from the original residue-based unwrapper falls below a coverage threshold. In North America continental processing, first experiments show the strip void area is reduced by more than 50% and the number of strip void patches is reduced by 40%. Patch boundary voids are mitigated by reprocessing with a different starting burst and merging the unwrapping results. We also updated a low-resolution elevation database to aid with unwrapping bootstrapping, retaining isolated component of unwrapped phase, and assessing the quality of the strip DEMs. We introduce a height ripple error correction to reduce artifacts in the strip elevation data. These ripples are a few meters in size with along-track spatial scales of tens of kilometers and are due to uncompensated mast motion most pronounced after Shuttle roll angle adjustment maneuvers. We developed an along-track filter utilizing differences between the SRTM heights and ICESat lidar elevation data. For a test using all data over North America, the algorithm reduced the ICESat-SRTM bias from 80 cm to 3 cm and the RMS from 5m to 4m. After merging and regridding the SRTM strip DEMs into 1x1-degree tiles, remaining voids are primarily filled with the ASTER-derived Global DEM. We use a Delta Surface Fill method to rubbersheet fill data across the void for

  17. Analysis of forest and forest clearings in Amazonia with Landsat and Shuttle Imaging Radar-A data (United States)

    Stone, Thomas A.; Woodwell, George M.


    Landsat and Shuttle Imaging Radar-A L band (23.5 cm wavelength) data from 1981 were used to analyze areas of intact tropical forest and areas recently cleared from forest for agriculture and pasture in Mato Grosso, Brazil. Portions of SIR-A Data Takes #24C and #31 film were digitized using a microdensitometer. Landsat MSS data of July 1981 were also examined. The digital values from SIR-A DT 31 were compared with the normalized difference vegetation index values (NDVI) from the Landsat data for the same sites. Contrary to expectations some cleared areas had brighter radar responses than surrounding forest. The explanation seems to be that a recently cleared forest (cut and burned during the dry season) is texturally very rough as the exposed standing and fallen boles and woody litter may function as effective corner or dihedral reflectors. Combining radar data with NDVI data may help to assess the relative age of forest clearings and determine differences in both woody and green leaf biomass of primary and secondary tropical forests.

  18. Structural analysis of three extensional detachment faults with data from the 2000 Space-Shuttle Radar Topography Mission (United States)

    Spencer, J.E.


    The Space-Shuttle Radar Topography Mission provided geologists with a detailed digital elevation model of most of Earth's land surface. This new database is used here for structural analysis of grooved surfaces interpreted to be the exhumed footwalls of three active or recently active extensional detachment faults. Exhumed fault footwalls, each with an areal extent of one hundred to several hundred square kilometers, make up much of Dayman dome in eastern Papua New Guinea, the western Gurla Mandhata massif in the central Himalaya, and the northern Tokorondo Mountains in central Sulawesi, Indonesia. Footwall curvature in profile varies from planar to slightly convex upward at Gurla Mandhata to strongly convex upward at northwestern Dayman dome. Fault curvature decreases away from the trace of the bounding detachment fault in western Dayman dome and in the Tokorondo massif, suggesting footwall flattening (reduction in curvature) following exhumation. Grooves of highly variable wavelength and amplitude reveal extension direction, although structural processes of groove genesis may be diverse.

  19. Shuttle orbiter Ku-band radar/communications system design evaluation. Deliverable test equipment evaluation (United States)

    Maronde, R. G.


    The Ku-band test equipment, known as the Deliverable System Test equipment (DSTE), is reviewed and evaluated. The DSTE is semiautomated and computer programs were generated for 14 communication mode tests and 17 radar mode tests. The 31 test modules provide a good cross section of tests with which to exercise the Ku-band system; however, it is very limited when being used to verify Ku-band system performance. More detailed test descriptions are needed, and a major area of concern is the DSTE sell-off procedure which is inadequate.

  20. Experimental measurements of the Space Shuttle main engine fuel and oxygen turbopump vibration characteristics (United States)

    Gunter, E. J.; Flack, R. D.


    The vibration characteristics of the SSME (Space Shuttle main engine) are dealt with. The Space Shuttle engine consists of a main rocket nozzle and attached to it are high pressure fuel and oxygen pumps. Various vibration problems have been encountered with both the hydrogen and oxygen pumps. The vibration spectrum of the hydrogen and oxygen pumps has been analyzed by various techniques using synchronous tracking filters and FFT analyzers. The experimental data has been correlated to theoretical predictions of resonance frequencies.

  1. Target acquisition dynamics with application to the rendezvous radar of the Space Shuttle orbiter (United States)

    Kassem, A. M.; McQuillan, W. F.


    A statistical approach is used in formulating the transition from search to automatic angle tracking for search and tracking radars. The angular separation between the target position and the antenna line of sight following detection is derived as a function of both target and system parameters. Using a simple computer program, the probability density function of the angular separation at the end of the acquisition phase is found as a function of both target and system parameters. The results can then be used to develop specifications for the antenna control servo for established limits on target angular rates so as to obtain a high probability of successful transition from search to automatic angle tracking.

  2. Detection of Forest Clear-Cuts with Shuttle Radar Topography Mission (SRTM and Tandem-X InSAR Data

    Directory of Open Access Journals (Sweden)

    Dan J. Weydahl


    Full Text Available The aim of this study was to determine whether forest clear-cuts during 2000–2011 could be detected as a decrease in surface height by combining Digital Surface Models (DSMs from the Shuttle Radar Topography Mission (SRTM and Tandem-X, and to evaluate the performance of this method using SRTM X- and C-band data as references representing the heights before logging. The study area was located in a Norway spruce-dominated forest estate in southeastern Norway. We interpolated 11-year DSM changes into a 10 m × 10 m raster, and averaged these changes per forest stand. Based on threshold values for DSM decreases we classified the pixels and stands into the categories “clear-cut” and “not clear-cut”, and compared this to a complete record of logged stands during 2000–2011. The classification accuracy was moderate or fairly good. A correct detection was achieved for 59%–67% of the clear-cut stands. Omission errors were most common, occurring in 33%–42% of the stands. Commission errors were found in 13%–21% of the clear-cut stands. The results obtained for X-band SRTM were only marginally better than for C-band. In conclusion, the combination of SRTM and Tandem-X has the potential of providing near global data sets for the recent 12 years’ logging, which should be particularly valuable for deforestation mapping.

  3. High-resolution polarimetric X-band weather radar observations at the Cabauw Experimental Site for Atmospheric Research

    NARCIS (Netherlands)

    Otto, T.; Russchenberg, H.W.J.


    In 2007, the horizontally scanning polarimetric X-band radar IDRA (IRCTR Drizzle Radar) was installed on top of the 213 m high mast at the Dutch meteorological observatory Cabauw Experimental Site for Atmospheric Research (CESAR) at Netherlands. This radar complements a large variety of measurement

  4. Experimental Research of HF Passive Radar Based on DRM Digital AM Broadcasting

    Directory of Open Access Journals (Sweden)

    Wan Xian-rong


    Full Text Available This paper gives the experimental research of HF Passive Bistatic Radar (HFPBR based on Digital Radio Mondiale (DRM digital AM broadcasting that have been first carried out in China, using the newly-developed all-digital active/passive integrated HF surface wave radar system. The principle, key techniques, experimental equipment, and preliminary results are introduced about this new radar system. Based on analysis of the measurement data, experimental results under different scenarios including surface-wave, sky-wave, and hybrid sky-surface propagation modes are presented, which have proved, for the first time worldwide, the technical feasibility of using DRM broadcasting signal for over-the-horizon detection by field experiment and formed the theoretical and experimental basis for the further development of HFPBR.

  5. Bridge Testing With Ground-Based Interferometric Radar: Experimental Results (United States)

    Chiara, P.; Morelli, A.


    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.

  6. Experimental Research of HF Passive Radar Based on DRM Digital AM Broadcasting

    Directory of Open Access Journals (Sweden)

    Wan Xian-rong


    Full Text Available Radio Mondiale (DRM digital AM broadcasting that have been first carried out in China, using the newly-developed all-digital active/passive integrated HF surface wave radar system. The principle, key techniques, experimental equipment, and preliminary results are introduced about this new radar system. Based on analysis of the measurement data, experimental results under different scenarios including surface-wave, sky-wave, and hybrid sky-surface propagation modes are presented, which have proved, for the first time worldwide, the technical feasibility of using DRM broadcasting signal for over-the-horizon detection by field experiment and formed the theoretical and experimental basis for the further development of HFPBR.

  7. Experimental feasibility of multistatic holography for breast microwave radar image reconstruction. (United States)

    Flores-Tapia, Daniel; Rodriguez, Diego; Solis, Mario; Kopotun, Nikita; Latif, Saeed; Maizlish, Oleksandr; Fu, Lei; Gui, Yonsheng; Hu, Can-Ming; Pistorius, Stephen


    The goal of this study was to assess the experimental feasibility of circular multistatic holography, a novel breast microwave radar reconstruction approach, using experimental datasets recorded using a preclinical experimental setup. The performance of this approach was quantitatively evaluated by calculating the signal to clutter ratio (SCR), contrast to clutter ratio (CCR), tumor to fibroglandular response ratio (TFRR), spatial accuracy, and reconstruction time. Five datasets were recorded using synthetic phantoms with the dielectric properties of breast tissue in the 1-6 GHz range using a custom radar system developed by the authors. The datasets contained synthetic structures that mimic the dielectric properties of fibroglandular breast tissues. Four of these datasets the authors covered an 8 mm inclusion that emulated a tumor. A custom microwave radar system developed at the University of Manitoba was used to record the radar responses from the phantoms. The datasets were reconstructed using the proposed multistatic approach as well as with a monostatic holography approach that has been previously shown to yield the images with the highest contrast and focal quality. For all reconstructions, the location of the synthetic tumors in the experimental setup was consistent with the position in the both the monostatic and multistatic reconstructed images. The average spatial error was less than 4 mm, which is half the spatial resolution of the data acquisition system. The average SCR, CCR, and TFRR of the images reconstructed with the multistatic approach were 15.0, 9.4, and 10.0 dB, respectively. In comparison, monostatic images obtained using the datasets from the same experimental setups yielded average SCR, CCR, and TFRR values of 12.8, 4.9, and 5.9 dB. No artifacts, defined as responses generated by the reconstruction method of at least half the energy of the tumor signatures, were noted in the multistatic reconstructions. The average execution time of the

  8. Model-Based Estimation of Forest Canopy Height in Red and Austrian Pine Stands Using Shuttle Radar Topography Mission and Ancillary Data: a Proof-of-Concept Study

    Energy Technology Data Exchange (ETDEWEB)

    Brown Jr., C G; Sarabandi, K; Pierce, L E


    In this paper, accurate tree stand height retrieval is demonstrated using C-band Shuttle Radar Topography Mission (SRTM) height and ancillary data. The tree height retrieval algorithm is based on modeling uniform tree stands with a single layer of randomly oriented vegetation particles. For such scattering media, the scattering phase center height, as measured by SRTM, is a function of tree height, incidence angle, and the extinction coefficient of the medium. The extinction coefficient for uniform tree stands is calculated as a function of tree height and density using allometric equations and a fractal tree model. The accuracy of the proposed algorithm is demonstrated using SRTM and TOPSAR data for 15 red pine and Austrian pine stands (TOPSAR is an airborne interferometric synthetic aperture radar). The algorithm yields root-mean-square (rms) errors of 2.5-3.6 m, which is a substantial improvement over the 6.8-8.3-m rms errors from the raw SRTM minus National Elevation Dataset Heights.

  9. Synthetic aperture radar images of ocean waves, theories of imaging physics and experimental tests (United States)

    Vesecky, J. F.; Durden, S. L.; Smith, M. P.; Napolitano, D. A.


    The physical mechanism for the synthetic Aperture Radar (SAR) imaging of ocean waves is investigated through the use of analytical models. The models are tested by comparison with data sets from the SEASAT mission and airborne SAR's. Dominant ocean wavelengths from SAR estimates are biased towards longer wavelengths. The quasispecular scattering mechanism agrees with experimental data. The Doppler shift for ship wakes is that of the mean sea surface.

  10. Experimental and rendering-based investigation of laser radar cross sections of small unmanned aerial vehicles (United States)

    Laurenzis, Martin; Bacher, Emmanuel; Christnacher, Frank


    Laser imaging systems are prominent candidates for detection and tracking of small unmanned aerial vehicles (UAVs) in current and future security scenarios. Laser reflection characteristics for laser imaging (e.g., laser gated viewing) of small UAVs are investigated to determine their laser radar cross section (LRCS) by analyzing the intensity distribution of laser reflection in high resolution images. For the first time, LRCSs are determined in a combined experimental and computational approaches by high resolution laser gated viewing and three-dimensional rendering. An optimized simple surface model is calculated taking into account diffuse and specular reflectance properties based on the Oren-Nayar and the Cook-Torrance reflectance models, respectively.

  11. Geomorphology Classification of Shandong Province Based on Digital Elevation Model in the 1 Arc-second Format of Shuttle Radar Topography Mission Data (United States)

    Fu, Jundong; Zhang, Guangcheng; Wang, Lei; Xia, Nuan


    Based on gigital elevation model in the 1 arc-second format of shuttle radar topography mission data, using the window analysis and mean change point analysis of geographic information system (GIS) technology, programmed with python modules this, automatically extracted and calculated geomorphic elements of Shandong province. The best access to quantitatively study area relief amplitude of statistical area. According to Chinese landscape classification standard, the landscape type in Shandong province was divided into 8 types: low altitude plain, medium altitude plain, low altitude platform, medium altitude platform, low altitude hills, medium altitude hills, low relief mountain, medium relief mountain and the percentages of Shandong province’s total area are as follows: 12.72%, 0.01%, 36.38%, 0.24%, 17.26%, 15.64%, 11.1%, 6.65%. The results of landforms are basically the same as the overall terrain of Shandong Province, Shandong province’s total area, and the study can quantitatively and scientifically provide reference for the classification of landforms in Shandong province.

  12. Structural And Lithological Reconnaissance Studies Of Part Of North Central Nigeria Using Landsat Enhanced Thematic Mapper Plus Etm And Shuttle Radar Topography Mission Srtm Satellite Imageries

    Directory of Open Access Journals (Sweden)

    Apata Dolapo Moses


    Full Text Available The Structural and Lithological studies of a part of North Central Nigeria which lies between latitudes 9o11l21.87N and 11o 3l37.29N and longitudes 7o 43l 53.01E and 6o 25l50.65 E covering an area of 170 km by 183 km was carried out using Landsat enhanced thematic mapper plusETM and shuttle radar topography mission satellite imageries SRTM. These imageries were visually and digitally interpreted using softwares such as ArcGis 9.2 Global mapper Multispec Ilwis 3.4 and Microsoft Paint. The zone is comprised of cellar basement rocks such as Granite Migmatite Gneiss Schist and Quartzite which show megascopic structures such as joints faults and folds. The drainage pattern within the area which include dendritic rectangular braided and annular were identified and their geologic implication was inferred. A Rock Outcrop map and a Lineament map of the study area was constructed. Rossete diagram made from the lineaments shows that the principal Strike direction in the study area is NNE-SSW which conforms to the general structural trend direction in the Nigerian Basement.

  13. Gently dipping normal faults identified with Space Shuttle radar topography data in central Sulawesi, Indonesia, and some implications for fault mechanics (United States)

    Spencer, J.E.


    Space-shuttle radar topography data from central Sulawesi, Indonesia, reveal two corrugated, domal landforms, covering hundreds to thousands of square kilometers, that are bounded to the north by an abrupt transition to typical hilly to mountainous topography. These domal landforms are readily interpreted as metamorphic core complexes, an interpretation consistent with a single previous field study, and the abrupt northward transition in topographic style is interpreted as marking the trace of two extensional detachment faults that are active or were recently active. Fault dip, as determined by the slope of exhumed fault footwalls, ranges from 4?? to 18??. Application of critical-taper theory to fault dip and hanging-wall surface slope, and to similar data from several other active or recently active core complexes, suggests a theoretical limit of three degrees for detachment-fault dip. This result appears to conflict with the dearth of seismological evidence for slip on faults dipping less than ~. 30??. The convex-upward form of the gently dipping fault footwalls, however, allows for greater fault dip at depths of earthquake initiation and dominant energy release. Thus, there may be no conflict between seismological and mapping studies for this class of faults. ?? 2011 Elsevier B.V.

  14. Real time breast microwave radar image reconstruction using circular holography: a study of experimental feasibility. (United States)

    Flores-Tapia, Daniel; Pistorius, Stephen


    The purpose of this paper is to assess the experimental feasibility of a novel breast microwave radar reconstruction approach, circular holography, using realistic experimental datasets recorded using a preclinical experimental setup. The performance of this approach was quantitatively evaluated by calculating the signal to noise ratio, contrast to noise ratio, spatial accuracy, and reconstruction time. Six datasets were recorded, three corresponding to fatty cases and three containing synthetic dense tissue structures. Five of these datasets contained an 8 mm inclusion that emulated a malignant lesion. The data were acquired from synthetic phantoms that mimic the dielectric properties of breast tissues in the 1-6 GHz range using a custom experimental breast microwave radar system. The spatial accuracy and signal to noise ratio of the reconstructed was calculated for all the reconstructed images. The contrast to noise ratio of the reconstructed images corresponding to the datasets containing fibroglandular tissue regions was determined. This was done to evaluate the ability of the circular holographic method to provide images in which the responses from tumors can be distinguished from adjacent dense tissue structures. The execution time required to form the images was also measured to evaluate the data throughput of the holographic approach. For all the reconstructed datasets, the location of the synthetic tumors in the experimental setup was consistent with its position in the reconstructed image. The average spatial error was 2.2 mm, which is less than half the spatial resolution of the data acquisition system. The average signal to noise ratio of the reconstructed images containing an artificial malignant lesion was 8.5 dB, while the average contrast to noise ratio was 6.7 dB. The reconstructed images presented no artifacts. The average execution time of the images formed using the proposed approach was 5 ms, which is six orders of magnitude faster than current

  15. Experimental Proof of the Characteristics of Short-Range FM Radar Converted Signal Spectrum for a Smooth Surface

    Directory of Open Access Journals (Sweden)

    Brodņevs Deniss


    Full Text Available This paper presents a natural experiment of the spectral processing of 4.3 GHz Frequency Modulated Continuous Wave Radar (FMCWR converted signal. The FMCWR antennas are fixed above a smooth reflective surface. The converted signal spectrum is theoretically calculated and compared with the experimental data.

  16. Experimental study of dual polarized radar return from the sea surface (United States)

    Ermakov, S. A.; Kapustin, I. A.; Lavrova, O. Yu.; Molkov, A. A.; Sergievskaya, I. A.; Shomina, O. V.


    Dual-polarized microwave radars are of particular interest nowadays as perspective tool of ocean remote sensing. Microwave radar backscattering at moderate and large incidence angles according to conventional models is determined by resonance (Bragg) surface waves typically of cm-scale wavelength range. Some recent experiments have indicated, however, that an additional, non Bragg component (NBC) contributes to the radar return. The latter is considered to occur due to wave breaking. At present our understanding of the nature of different components of radar return is still poor. This paper presents results of field experiment using an X-/C-/S-band Doppler radar operating at HH- and VVpolarizations. The intensity and radar Doppler shifts for Bragg and non Bragg components are retrieved from measurements of VV and HH radar returns. Analysis of a ratio of VV and HH radar backscatter - polarization ratio (PR) has demonstrated a significant role of a non Bragg component. NBC contributes significantly to the total radar backscatter, in particular, at moderate incidence angles (about 50-70 deg.) it is 2-3 times smaller than VV Bragg component and several times larger that HH Bragg component. Both NBC and BC depend on azimuth angle, being minimal for cross wind direction, but NBC is more isotropic than BC. It is obtained that velocities of scatterers retrieved from radar Doppler shifts are different for Bragg waves and for non Bragg component; NBC structures are "faster" than Bragg waves particularly for upwind radar observations. Bragg components propagate approximately with phase velocities of linear gravity-capillary waves (when accounting for wind drift). Velocities of NBC scatterers depend on radar band, being the largest for S-band and the smallest at X-band, this means that different structures on the water surface are responsible for non Bragg scattering in a given radar band.

  17. Experimental evaluation of penetration capabilities of a Geiger-mode APD array laser radar system (United States)

    Jonsson, Per; Tulldahl, Michael; Hedborg, Julia; Henriksson, Markus; Sjöqvist, Lars


    Laser radar 3D imaging has the potential to improve target recognition in many scenarios. One case that is challenging for most optical sensors is to recognize targets hidden in vegetation or behind camouflage. The range resolution of timeof- flight 3D sensors allows segmentation of obscuration and target if the surfaces are separated far enough so that they can be resolved as two distances. Systems based on time-correlated single-photon counting (TCSPC) have the potential to resolve surfaces closer to each other compared to laser radar systems based on proportional mode detection technologies and is therefore especially interesting. Photon counting detection is commonly performed with Geigermode Avalanche Photodiodes (GmAPD) that have the disadvantage that they can only detect one photon per laser pulse per pixel. A strong return from an obscuring object may saturate the detector and thus limit the possibility to detect the hidden target even if photons from the target reach the detector. The operational range where good foliage penetration is observed is therefore relatively narrow for GmAPD systems. In this paper we investigate the penetration capability through semi-transparent surfaces for a laser radar with a 128×32 pixel GmAPD array and a 1542 nm wavelength laser operating at a pulse repetition frequency of 90 kHz. In the evaluation a screen was placed behind different canvases with varying transmissions and the detected signals from the surfaces for different laser intensities were measured. The maximum return from the second surface occurs when the total detection probability is around 0.65-0.75 per pulse. At higher laser excitation power the signal from the second surface decreases. To optimize the foliage penetration capability it is thus necessary to adaptively control the laser power to keep the returned signal within this region. In addition to the experimental results, simulations to study the influence of the pulse energy on penetration through

  18. An analytical and experimental study for surface heat flux determination. [in Space Shuttle Orbiter thermal protection system (United States)

    Williams, S. D.; Curry, D. M.


    A numerical method by which data from a single embedded thermocouple can be used to predict the transient thermal environment for both high- and low-conductivity materials is described. The results of an investigation performed to verify the method clearly demonstrate that accurate transient surface heating conditions can be obtained from a thermocouple 1.016 cm from the surface in a low-conductivity material. Space Shuttle Orbiter thermal protection system materials having temperature- and pressure-dependent properties and typical Orbiter entry heating conditions were used to verify the accuracy of the analytical procedure. Analytically generated, as well as experimental, data were used to compare predicted and measured surface temperatures.

  19. Comparison of high-latitude thermospheric meridionalwinds I: optical and radar experimental comparisons

    Directory of Open Access Journals (Sweden)

    E. M. Griffin


    Full Text Available Thermospheric neutral winds at Kiruna, Sweden (67.4°N, 20.4°E are compared using both direct optical Fabry-Perot Interferometer (FPI measurements and those derived from European incoherent scatter radar (EISCAT measurements. This combination of experimental data sets, both covering well over a solar cycle of data, allows for a unique comparison of the thermospheric meridional component of the neutral wind as observed by different experimental techniques. Uniquely in this study the EISCAT measurements are used to provide winds for comparison using two separate techniques: the most popular method based on the work of Salah and Holt (1974 and the Meridional Wind Model (MWM (Miller et al., 1997 application of servo theory. The balance of forces at this location that produces the observed diurnal pattern are investigated using output from the Coupled Thermosphere and Ionosphere (CTIM numerical model. Along with detailed comparisons from short periods the climatological behaviour of the winds have been investigated for seasonal and solar cycle dependence using the experimental techniques. While there are features which are consistent between the 3 techniques, such as the evidence of the equinoctial asymmetry, there are also significant differences between the techniques both in terms of trends and absolute values. It is clear from this and previous studies that the high-latitude representation of the thermospheric neutral winds from the empirical Horizontal Wind Model (HWM, though improved from earlier versions, lacks accuracy in many conditions. The relative merits of each technique are discussed and while none of the techniques provides the perfect data set to address model performance at high-latitude, one or more needs to be included in future HWM reformulations. Key words. Meteorology and atmospheric dynamics (thermospheric dynamics, Ionosphere (ionosphere-atmosphere interactions, auroral ionosphere

  20. Comparison of high-latitude thermospheric meridionalwinds I: optical and radar experimental comparisons

    Directory of Open Access Journals (Sweden)

    E. M. Griffin


    Full Text Available Thermospheric neutral winds at Kiruna, Sweden (67.4°N, 20.4°E are compared using both direct optical Fabry-Perot Interferometer (FPI measurements and those derived from European incoherent scatter radar (EISCAT measurements. This combination of experimental data sets, both covering well over a solar cycle of data, allows for a unique comparison of the thermospheric meridional component of the neutral wind as observed by different experimental techniques. Uniquely in this study the EISCAT measurements are used to provide winds for comparison using two separate techniques: the most popular method based on the work of Salah and Holt (1974 and the Meridional Wind Model (MWM (Miller et al., 1997 application of servo theory. The balance of forces at this location that produces the observed diurnal pattern are investigated using output from the Coupled Thermosphere and Ionosphere (CTIM numerical model. Along with detailed comparisons from short periods the climatological behaviour of the winds have been investigated for seasonal and solar cycle dependence using the experimental techniques. While there are features which are consistent between the 3 techniques, such as the evidence of the equinoctial asymmetry, there are also significant differences between the techniques both in terms of trends and absolute values. It is clear from this and previous studies that the high-latitude representation of the thermospheric neutral winds from the empirical Horizontal Wind Model (HWM, though improved from earlier versions, lacks accuracy in many conditions. The relative merits of each technique are discussed and while none of the techniques provides the perfect data set to address model performance at high-latitude, one or more needs to be included in future HWM reformulations.

    Key words. Meteorology and atmospheric dynamics (thermospheric dynamics, Ionosphere (ionosphere-atmosphere interactions, auroral ionosphere

  1. An Experimental and Numerical Study on Embedded Rebar Diameter in Concrete Using Ground Penetrating Radar

    Directory of Open Access Journals (Sweden)

    Md Istiaque Hasan


    Full Text Available High frequency ground penetrating radar (GPR has been widely used to detect and locate rebars in concrete. In this paper, a method of estimating the diameter of steel rebars in concrete with GPR is investigated. The relationship between the maximum normalized positive GPR amplitude from embedded rebars and the rebar diameter was established. Concrete samples with rebars of different diameters were cast and the maximum normalized amplitudes were recorded using a 2.6 GHz GPR antenna. Numerical models using GPRMAX software were developed and verified with the experimental data. The numerical models were then used to investigate the effect of dielectric constant of concrete and concrete cover on the maximum normalized amplitude. The results showed that there is an approximate linear relationship between the rebar diameter and the maximum GPR normalized amplitude. The developed models can be conveniently used to estimate the embedded rebar diameters in existing concrete with GPR scanning; if the concrete is homogeneous, the cover depth is known and the concrete dielectric constant is also known. The models will be highly beneficial in forensic investigations of existing concrete structures with unknown rebar sizes and locations.

  2. Stretching the Shuttle (United States)

    Furniss, Tim


    A review is presented of the modifications incorporated in the Shuttle Columbia to extend its duration and capabilities in preparation for this extended-duration orbiter (EDO) to fly missions of up to 16 days. Attention is given to the evolution of the program that has changed the Shuttle from a space truck on nominal seven-day sorties to a versatile vehicle that can perform as a space laboratory. Consideration is given to the provision of more electrical power and life support supplies and equipment, the CRYO wafer pallet, advanced general-purpose computers, and an improved radar-altimeter.

  3. [The error analysis and experimental verification of laser radar spectrum detection and terahertz time domain spectroscopy]. (United States)

    Liu, Wen-Tao; Li, Jing-Wen; Sun, Zhi-Hui


    Terahertz waves (THz, T-ray) lie between far-infrared and microwave in electromagnetic spectrum with frequency from 0.1 to 10 THz. Many chemical agent explosives show characteristic spectral features in the terahertz. Compared with conventional methods of detecting a variety of threats, such as weapons and chemical agent, THz radiation is low frequency and non-ionizing, and does not give rise to safety concerns. The present paper summarizes the latest progress in the application of terahertz time domain spectroscopy (THz-TDS) to chemical agent explosives. A kind of device on laser radar detecting and real time spectrum measuring was designed which measures the laser spectrum on the bases of Fourier optics and optical signal processing. Wedge interferometer was used as the beam splitter to wipe off the background light and detect the laser and measure the spectrum. The result indicates that 10 ns laser radar pulse can be detected and many factors affecting experiments are also introduced. The combination of laser radar spectrum detecting, THz-TDS, modern pattern recognition and signal processing technology is the developing trend of remote detection for chemical agent explosives.

  4. Experimental and Computational Study of an Unexpected Iron-Catalyzed Carboetherification by Cooperative Metal and Ligand Substrate Interaction and Proton Shuttling

    KAUST Repository

    El-Sepelgy, Osama


    An iron-catalyzed cycloisomerization of allenols to deoxygenated pyranose glycals has been developed. Combined experimental and computational studies show that the iron complex exhibits a dual catalytic role in that the non-innocent cyclopentadienone ligand acts as proton shuttle by initial hydrogen abstraction from the alcohol and by facilitating protonation and deprotonation events in the isomerization and demetalation steps. Molecular orbital analysis provides insight into the unexpected and selective formation of the 3,4-dihydro-2H-pyran.

  5. Experimental evaluation of battery cells for space-based radar application (United States)

    Maskell, Craig A.; Metcalfe, John R.


    A test program was conducted to characterize five space-quality nickel-hydrogen (NiH2) battery cells. A subset of those tests was also done on five commercial nickel-cadmium (NiCd) cells, for correlation to the characteristics of an Energy Storage Unit Simulator. The test program implemented the recommendations of a 1991 study, as reported to IECEC-92. The findings of the tests are summarized, and expected impacts on the performance of the electrical power system (EPS) of a large space-based radar (SBR) surveillance satellite are derived. The main characteristics examined and compared were terminal voltage (average and transient) and capacity through discharge, equivalent series resistance, derived inductance and capacitance, charge return efficiency, and inter-pulse charge effectiveness.

  6. Java Radar Analysis Tool (United States)

    Zaczek, Mariusz P.


    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.

  7. Experimental studies of microwave propagation through fires for through-wall, search-and-rescue radar in firefighting (United States)

    Temme, Andrew Kenneth Gerken

    Finding people trapped inside of a burning house is extremely difficult, dangerous, and time consuming. Smoke, heat, unfamiliar floor plans, and possible structural collapse all combine to challenge a firefighter's ability to find a person. Thermal imaging cameras, the most advanced technology available to firefighters today, are able to see through smoke but are unable to see through walls and household items. Through-wall radar and vital-sign detection radar offer an imaging modality that may be able to help firefighters find victims from outside of a room or even a house. Flames can interact with electromagnetic (radar) waves because the flames create a weakly-ionized plasma. Previous work has looked at small flames fueled by pure gases or flames from wildfires. Combustable items in a house are typically petroleum-based products that have different combustion reactions compared to previously studied flames and fire-induced plasmas. Because of this, it is unknown how electromagnetic waves interact with flames found in a house fire. This dissertation investigates the question of how electromagnetic waves interact with flames in a house fire. This is an open problem, with many variables, that poses a subtle and difficult measurement task. This work focuses on creating experimental techniques to explore this problem. From an electromagnetic metrology perspective, the physical phenomena of interest are difficult to measure due to ill-defined physical boundaries, characteristics lengths of varying magnitude, inhomogeneity, and varying time scales. The experimental methods studied here primarily focus on transmission measurements through flames a few feet in height. Additionally, this work presents a proof-of-concept two-wire transmission line for bench-scale, material-characterization of solids, liquids, gases, and flames. Results from this work provide a metrological foundation for future studies in this area. An experimental setup that can withstand direct exposure

  8. Radar activities of the DFVLR Institute for Radio Frequency Technology (United States)

    Keydel, W.


    Aerospace research and the respective applications microwave tasks with respect to remote sensing, position finding and communication are discussed. The radar activities are directed at point targets, area targets and volume targets; they center around signature research for earth and ocean remote sensing, target recognition, reconnaissance and camouflage and imaging and area observation radar techniques (SAR and SLAR). The radar activities cover a frequency range from 1 GHz up to 94 GHz. The radar program is oriented to four possible application levels: ground, air, shuttle orbits and satellite orbits. Ground based studies and measurements, airborne scatterometers and imaging radars, a space shuttle radar, the MRSE, and follow on experiments are considered.

  9. Spaceborne Imaging Radar Symposium (United States)

    Elachi, C.


    An overview of the present state of the art in the different scientific and technological fields related to spaceborne imaging radars was presented. The data acquired with the SEASAT SAR (1978) and Shuttle Imaging Radar, SIR-A (1981) clearly demonstrated the important emphasis in the 80's is going to be on in-depth research investigations conducted with the more flexible and sophisticated SIR series instruments and on long term monitoring of geophysical phenomena conducted from free-flying platforms such as ERS-1 and RADARSAT.

  10. Computational methods for frictional contact with applications to the Space Shuttle orbiter nose-gear tire: Comparisons of experimental measurements and analytical predictions (United States)

    Tanner, John A.


    A computational procedure is presented for the solution of frictional contact problems for aircraft tires. A Space Shuttle nose-gear tire is modeled using a two-dimensional laminated anisotropic shell theory which includes the effects of variations in material and geometric parameters, transverse-shear deformation, and geometric nonlinearities. Contact conditions are incorporated into the formulation by using a perturbed Lagrangian approach with the fundamental unknowns consisting of the stress resultants, the generalized displacements, and the Lagrange multipliers associated with both contact and friction conditions. The contact-friction algorithm is based on a modified Coulomb friction law. A modified two-field, mixed-variational principle is used to obtain elemental arrays. This modification consists of augmenting the functional of that principle by two terms: the Lagrange multiplier vector associated with normal and tangential node contact-load intensities and a regularization term that is quadratic in the Lagrange multiplier vector. These capabilities and computational features are incorporated into an in-house computer code. Experimental measurements were taken to define the response of the Space Shuttle nose-gear tire to inflation-pressure loads and to inflation-pressure loads combined with normal static loads against a rigid flat plate. These experimental results describe the meridional growth of the tire cross section caused by inflation loading, the static load-deflection characteristics of the tire, the geometry of the tire footprint under static loading conditions, and the normal and tangential load-intensity distributions in the tire footprint for the various static vertical-loading conditions. Numerical results were obtained for the Space Shuttle nose-gear tire subjected to inflation pressure loads and combined inflation pressure and contact loads against a rigid flat plate. The experimental measurements and the numerical results are compared.

  11. Status Of Imaging Radar Polarimetry (United States)

    Van Zyl, Jakob J.; Zebker, Howard A.


    Report pulls together information on imaging radar polarimetry from a variety of sources. Topics include theory, equipment, and experimental data. Reviews state of the art, examines current applicable developments in radar equipment, describes recording and processing of radar polarimetric measurements, and discusses interpretation and application of resulting polarimetric images.

  12. Experimental Verification of Multiple-input Multiple Output (MIMO) Beamforming Capabilities Using a Time-division Coherent MIMO Radar (United States)


    à 8 canaux et à répartition dans le temps sont discutés. Des données de radar à réseau à éléments en phase, obtenus avec une ap- proche mixte...obtenus avec un radar MIMO de bande X à 8 canaux et à répartition dans le temps, clarifient l’exacti- tude de l’estimation de l’angle des radars MIMO...However, where further distribution (beyond the audience specified in (11)) is possible, a wider announcement audience may be selected.) Unlimited 13

  13. Experimentally achieving borehole antenna radar directivity in the time domain in the presence of strong mutual coupling

    CSIR Research Space (South Africa)

    Vogt, D


    Full Text Available published borehole radar antennas have achieved directivity by post processing data received in the frequency domain, or by constructing an aperture antenna, where borehole dimensions allowed this. In this paper, a time-domain technique is investigated...

  14. Out-of-sequence reactivation of the Munsiari thrust in the Relli River basin, Darjiling Himalaya, India: Insights from Shuttle Radar Topography Mission digital elevation model-based geomorphic indices (United States)

    Mukul, Manas; Srivastava, Vinee; Mukul, Malay


    Quantitative tectonic geomorphology has emerged as a powerful discipline for studying evolution of topography, landscapes, and neotectonics using geomorphic indices computed from digital elevation data such as the Shuttle Radar Topography Mission (SRTM) data. We computed SRTM-based geomorphic indices to study neotectonics in the Relli River basin in the Darjiling Himalaya. We also used Real Time Kinematic Global Positioning System (RTKGPS) independent checkpoints to assess the quality of the SRTM data used to compute the geomorphic indices along with their uncertainties. Our analysis revealed that though the SRTM C-Band 90-m resolution (C90) digital elevation data has been used extensively for geomorphic studies, the 30-m resolution (C30) data were significantly more accurate. Moreover, geomorphic indices computed using SRTM C30 and C90 elevations in the Relli basin indicate that normalized, nondimensional indices such as the relief ratio (Rh), hypsometric integral (HI), basin elongation (Re), and valley floor width-to-height ratio (Vf) are statistically indistinguishable with uncertainty (1σ) at least an order of magnitude below the index value. The geomorphic indices in the Relli basin reveal neotectonic activity in the Munsiari thrust (MT) fault zone and intraformational faults in its footwall in the Lesser Himalayan rocks and also indicate that the basin is at an early mature stage close to equilibrium between tectonic and erosional process. However, analysis of the uncertainties associated with the indices suggest that the normalized or nondimensional geomorphic indices have the lowest uncertainties and that neotectonics in the Relli basin may only be confined to reactivation in the MT. The reactivation in the MT fault zone by out-of-sequence neotectonics implies the possibility of large earthquake events in the Darjiling Himalaya and significant seismic and landslide hazard for populations in large towns specifically located on the MT. Our new approach of

  15. Quantum radar

    CERN Document Server

    Lanzagorta, Marco


    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

  16. Shuttle requests

    CERN Document Server


    Please note that starting from 1 March 2007, the shuttle requests: for official visits or bidders' conferences on the CERN site; towards/from the airport or central Geneva; for long distances, shall be made via or by calling 77777. The radio taxi will still be reachable at 76969. TS/FM Group

  17. Radar Chart (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...

  18. CERN Shuttle

    CERN Document Server

    General Infrastructure Services Department


    As of Monday 21 February, a new schedule will come into effect for the Airport Shuttle (circuit No. 4) at the end of the afternoon: Last departure at 7:00 pm from Main Buildig, (Bldg. 500) to Airport (instead of 5:10 p.m.); Last departure from Airport to CERN, Main Buildig, (Bldg. 500), at 7:30 p.m. (instead of 5:40 p.m.). Group GS-IS

  19. Modification of Experimental Protocols for a Space Shuttle Flight and Applications for the Analysis of Cytoskeletal Structures During Fertilization, Cell Division , and Development in Sea Urchin Embryos (United States)

    Chakrabarti, Amitabha; Stoecker, Andrew; Schatten, Heide


    To explore the role of microgravity on cytoskeletal organization and skeletal calcium deposition during fertilization, cell division, and early development, the sea urchin was chosen as a model developmental system. Methods were developed to employ light, immunofluorescence, and electron microscopy on cultures being prepared for flight on the Space Shuttle. For analysis of microfilaments, microtubules, centrosomes, and calcium-requiring events, our standard laboratory protocols had to be modified substantially for experimentation on the Space Shuttle. All manipulations were carried out in a closed culture chamber containing 35 ml artificial sea water as a culture fluid. Unfertilized eggs stored for 24 hours in these chambers were fertilized with sperm diluted in sea water and fixed with concentrated fixatives for final fixation in formaldehyde, taxol, EGTA, and MgCl2(exp -6)H2O for 1 cell to 16 cell stages to preserve cytoskeletal structures for simultaneous analysis with light, immunofluorescence, and electron microscopy, and 1.5 percent glutaraldehyde and 0.4 percent formaldehyde for blastula and plueus stages. The fixed samples wre maintained in chambers without degradation for up to two weeks after which the specimens were processed and analyzed with routine methods. Since complex manipulations are not possible in the closed chambers, the fertilization coat was removed from fixation using 0.5 percent freshly prepared sodium thioglycolate solution at pH 10.0 which provided reliable immunofluorescence staining for microtubules. Sperm/egg fusion, mitosis, cytokinesis, and calcium deposition during spicule formatin in early embryogenesis were found to be without artificial alterations when compared to cells fixed fresh and processed with conventional methods.

  20. Space-time Characteristics and Experimental Analysis of Broadening First-order Sea Clutter in HF Hybrid Sky-surface Wave Radar

    Directory of Open Access Journals (Sweden)

    Y.J. Li


    Full Text Available In high frequency (HF hybrid sky-surface wave radar, the first-order sea clutter broadening is very complex and serious under the influence of ionosphere and bistatic angle, which affects the detection of ship target. This paper analyzes the space-time characteristics based on the HF sky-surface wave experimental system. We first introduce the basic structure, working principle and position principle based on our experimental system. Also analyzed is the influence of ionosphere and bistatic angle on the space-time coupling characteristics of broadening first-order sea clutter and the performance of space-time adaptive processing (STAP. Finally, the results of theoretic analysis are examined with the experimental data. Simulation results show that the results of experiment consist with that of theoretic analysis.

  1. Radar equations for modern radar

    CERN Document Server

    Barton, David K


    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

  2. Radar Image, Hokkaido, Japan (United States)


    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

  3. Relação entre as variáveis morfométricas extraídas de dados SRTM (Shuttle Radar Topography Mission e a vegetação do Parque Nacional de Brasília Relationship between morphometric variables extracted from SRTM (Shuttle Radar Topography Mission data and vegetation in Brasília National Park

    Directory of Open Access Journals (Sweden)

    Polyanna da Conceição Bispo


    Full Text Available Este trabalho visa ao estudo da relação entre a distribuição de fitofisionomias do Parque Nacional de Brasília (PNB e variáveis topográficas, para avaliar o potencial de dados SRTM isoladamente, como complemento aos dados tradicionalmente aplicados no sensoriamento remoto da vegetação. Esta relação foi verificada através de análises discriminantes entre o mapa de vegetação referência do PNB e as seguintes variáveis morfométricas: elevação, declividade, orientação de vertente, curvatura vertical e curvatura horizontal. Tais análises indicaram as classes de vegetação que podem ser separadas com base nas condições topográficas do terreno. As variáveis morfométricas mais importantes na distinção entre os tipos vegetacionais foram a elevação, a declividade e a orientação de vertente. Apesar de os dados morfométricos mostrarem potencial indicativo das classes de vegetação, as análises resultaram em discriminação em um nível aquém do detalhamento temático do mapa referência. Tal desempenho pode ser explicado pela incompatibilidade das escalas de variação exibidas entre os dados morfométricos em relação ao tamanho das unidades de mapeamento da vegetação. Além disso, a variação de tipos de vegetação do cerrado pode ser explicada por uma série de outros fatores além da topografia. Com base nas análises discriminantes das variáveis morfométricas, foi possível o mapeamento experimental da vegetação ao nível de subfisionomias.This paper aims to study the relationship between the distribution of vegetation in Brasilia National Park and topographic variables, to evaluate the potential of SRTM data alone, in addition to data traditionally used in remote sensing of vegetation. A map of vegetation of the area was used as a reference and the morphometric variables (elevation, slope, aspect and profile and plane curvatures were compared to the mapped units. Analyses indicated vegetation types easily

  4. Measuring human behaviour with radar

    NARCIS (Netherlands)

    Dorp, Ph. van


    The paper presents human motion measurements with the experimental Frequency Modulated Continuous Wave(FMCW) radar at TNO-FEL. The aim of these measurements is to analyse the Doppler velocity spectrum of humans. These analysis give insight in measuring human behaviour with radar for security

  5. Shuttle requests

    CERN Multimedia


    Please note that, to improve the service we provide, a new telephone number - 72500 - has been set up for all shuttle requests concerning: journeys within the CERN site, i.e. official visits or bidders' conferences; journeys to or from the airport or city centre; long-distance journeys. However, it will still be possible to submit requests in writing to Fm.Support@cern. The radio taxi can also still be reached on 76969. The TS/FM group would also like to inform you that details of all light logistics services (transport of persons, distribution and collection of parcels up to 1 tonne, distribution and collection of mail) can be found on the group's website: TS/FM Group 160239

  6. Air Defense Radar Operations Facility (United States)

    Federal Laboratory Consortium — Facility consists of laboratories, experimental test equipment including state-of-theart test bed radar, and test ranges. The facilities are used to design, develop,...

  7. Companies hone in on radar-docking technology (United States)

    Howell, Elizabeth


    As NASA prepares to retire the Space Shuttle next year, two private space firms have tested docking technology that could be used on the next generation of US spacecraft. In September, Canadian firm Neptec tested a new radar system on the Space Shuttle Discovery that allows spacecraft to dock more easily. Meanwhile, Space Exploration Technologies (SpaceX) based in California has revealed that it tested out a new proximity sensor, dubbed "Dragoneye", on an earlier shuttle mission in July.

  8. Experimental Evaluation of Several Key Factors Affecting Root Biomass Estimation by 1500 MHz Ground-Penetrating Radar

    Directory of Open Access Journals (Sweden)

    John C. Bain


    Full Text Available Accurate quantification of coarse roots without disturbance represents a gap in our understanding of belowground ecology. Ground penetrating radar (GPR has shown significant promise for coarse root detection and measurement, however root orientation relative to scanning transect direction, the difficulty identifying dead root mass, and the effects of root shadowing are all key factors affecting biomass estimation that require additional research. Specifically, many aspects of GPR applicability for coarse root measurement have not been tested with a full range of antenna frequencies. We tested the effects of multiple scanning directions, root crossover, and root versus soil moisture content in a sand-hill mixed oak community using a 1500 MHz antenna, which provides higher resolution than the oft used 900 MHz antenna. Combining four scanning directions produced a significant relationship between GPR signal reflectance and coarse root biomass (R2 = 0.75 (p < 0.01 and reduced variability encountered when fewer scanning directions were used. Additionally, significantly fewer roots were correctly identified when their moisture content was allowed to equalize with the surrounding soil (p < 0.01, providing evidence to support assertions that GPR cannot reliably identify dead root mass. The 1500 MHz antenna was able to identify roots in close proximity of each other as well as roots shadowed beneath shallower roots, providing higher precision than a 900 MHz antenna. As expected, using a 1500 MHz antenna eliminates some of the deficiency in precision observed in studies that utilized lower frequency antennas.

  9. Synthetic aperture radar capabilities in development

    Energy Technology Data Exchange (ETDEWEB)

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


    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.

  10. Weather Radar Stations (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...

  11. Study of atmospheric parameters measurements using MM-wave radar in synergy with LITE-2 (United States)

    Andrawis, Madeleine Y.


    The Lidar In-Space Technology Experiment, (LITE), has been developed, designed, and built by NASA Langley Research Center, to be flown on the space shuttle 'Discovery' on September 9, 1994. Lidar, which stands for light detecting and ranging, is a radar system that uses short pulses of laser light instead of radio waves in the case of the common radar. This space-based lidar offers atmospheric measurements of stratospheric and tropospheric aerosols, the planetary boundary layer, cloud top heights, and atmospheric temperature and density in the 10-40 km altitude range. A study is being done on the use, advantages, and limitations of a millimeterwave radar to be utilized in synergy with the Lidar system, for the LITE-2 experiment to be flown on a future space shuttle mission. The lower atmospheric attenuation, compared to infrared and optical frequencies, permits the millimeter-wave signals to penetrate through the clouds and measure multi-layered clouds, cloud thickness, and cloud-base height. These measurements would provide a useful input to radiation computations used in the operational numerical weather prediction models, and for forecasting. High power levels, optimum modulation, data processing, and high antenna gain are used to increase the operating range, while space environment, radar tradeoffs, and power availability are considered. Preliminary, numerical calculations are made, using the specifications of an experimental system constructed at Georgia Tech. The noncoherent 94 GHz millimeter-wave radar system has a pulsed output with peak value of 1 kW. The backscatter cross section of the particles to be measured, that are present in the volume covered by the beam footprint, is also studied.

  12. Bistatic radar

    CERN Document Server

    Willis, Nick


    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

  13. Ultra-Wideband Radar for Breath Tracking with Optical Fiber for Remote Reach Extension

    DEFF Research Database (Denmark)

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


    We report on the experimental demonstration of an UWB radar with fiber extension for remote breath tracking through 10 cm of concrete. The radar is based on telecom class equipment.......We report on the experimental demonstration of an UWB radar with fiber extension for remote breath tracking through 10 cm of concrete. The radar is based on telecom class equipment....

  14. Social Radar (United States)


    development and exploration of courses of action. Recent events suggest the great potential of social media as an important input for this 21st century...unrestricted data domain consisting of open source English and foreign language data of varying types, including social media  Engineering to process and...Ideology identification in multiple languages  Emotion analysis of social media for instability monitoring Social Radar RTA HFM-201/RSM

  15. Advances in bistatic radar

    CERN Document Server

    Willis, Nick


    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

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

    CERN Document Server

    Chen, Baixiao


    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

  17. Spaceborne radar for geoscientific applications in North China (United States)

    Guo, Hua-Dong; Wu, Guo-Xiang; Wang, Zhen-Song


    The Shuttle Imaging Radar-A and -B (SIR-A and SIR-B) carried on the Space Shuttle Columbia in Nov. 1981 and the Challenger in Oct. 1984 acquired images of test sites of North China. The Russian ALMAZ SAR also acquired imagery of part of this test site in Sep. 1992. In Nov. 1990, the airborne SAR developed by the Chinese Academy of Sciences (CAS/SAR) covered this area for the purpose of Chinese spaceborne radar development. By studying and analyzing these SAR data, positive results in geoscientific applications were achieved.

  18. Shuttle Wastewater Solution Characterization (United States)

    Adam, Niklas; Pham, Chau


    During the 31st shuttle mission to the International Space Station, STS-129, there was a clogging event in the shuttle wastewater tank. A routine wastewater dump was performed during the mission and before the dump was completed, degraded flow was observed. In order to complete the wastewater dump, flow had to be rerouted around the dump filter. As a result, a basic chemical and microbial investigation was performed to understand the shuttle wastewater system and perform mitigation tasks to prevent another blockage. Testing continued on the remaining shuttle flights wastewater and wastewater tank cleaning solutions. The results of the analyses and the effect of the mitigation steps are detailed in this paper.

  19. Space Radar Image of Phnom Phen, Cambodia (United States)


    This spaceborne radar image shows the city of Phnom Penh, the capital of Cambodia. Phnom Penh lies at the confluence of the Mekong River and the Basak Sab. The city was originally established in 1434 to succeed Angkor Thom as capital of the Khmer Nation. Phnom Penh is the bright blue and orange area west of the rivers, near the center of the image. The red, light blue and purple colors indicate differences in vegetation height and structure. Radar images like this one are being used by archaeologists to investigate ruins in the Angkor area in northern Cambodia. 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 15, 1994. The image is 27 kilometers by 27 kilometers (17 miles by 17 miles) and is centered at 11.5 degrees north latitude, 105.0 degrees East longitude. North is toward the upper right. 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 and vertically received; and blue is C-band, horizontally transmitted and 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.

  20. Shuttle with Cargo Bay (United States)


    The shuttle is a reusable launch vehicle that can maintain a consistent orbit and provide up to 17 days of high-quality microgravity conditions. The shuttle, which can accomodate a wide range of experiment apparatus, provides a laboratory environment in which scientists can conduct long-term investigations.

  1. Chemical Shuttle Additives in Lithium Ion Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Patterson, Mary


    The goals of this program were to discover and implement a redox shuttle that is compatible with large format lithium ion cells utilizing LiNi{sub 1/3}Mn{sub 1/3}Co{sub 1/3}O{sub 2} (NMC) cathode material and to understand the mechanism of redox shuttle action. Many redox shuttles, both commercially available and experimental, were tested and much fundamental information regarding the mechanism of redox shuttle action was discovered. In particular, studies surrounding the mechanism of the reduction of the oxidized redox shuttle at the carbon anode surface were particularly revealing. The initial redox shuttle candidate, namely 2-(pentafluorophenyl)-tetrafluoro-1,3,2-benzodioxaborole (BDB) supplied by Argonne National Laboratory (ANL, Lemont, Illinois), did not effectively protect cells containing NMC cathodes from overcharge. The ANL-RS2 redox shuttle molecule, namely 1,4-bis(2-methoxyethoxy)-2,5-di-tert-butyl-benzene, which is a derivative of the commercially successful redox shuttle 2,5-di-tert-butyl-1,4-dimethoxybenzene (DDB, 3M, St. Paul, Minnesota), is an effective redox shuttle for cells employing LiFePO{sub 4} (LFP) cathode material. The main advantage of ANL-RS2 over DDB is its larger solubility in electrolyte; however, ANL-RS2 is not as stable as DDB. This shuttle also may be effectively used to rebalance cells in strings that utilize LFP cathodes. The shuttle is compatible with both LTO and graphite anode materials although the cell with graphite degrades faster than the cell with LTO, possibly because of a reaction with the SEI layer. The degradation products of redox shuttle ANL-RS2 were positively identified. Commercially available redox shuttles Li{sub 2}B{sub 12}F{sub 12} (Air Products, Allentown, Pennsylvania and Showa Denko, Japan) and DDB were evaluated and were found to be stable and effective redox shuttles at low C-rates. The Li{sub 2}B{sub 12}F{sub 12} is suitable for lithium ion cells utilizing a high voltage cathode (potential that is higher

  2. Space Shuttle-Illustration (United States)


    The Space Shuttle represented an entirely new generation of space vehicles, the world's first reusable spacecraft. Unlike earlier expendable rockets, the Shuttle was designed to be launched over and over again and would serve as a system for ferrying payloads and persornel to and from Earth orbit. The Shuttle's major components are the orbiter spacecraft; the three main engines, with a combined thrust of more than 1.2 million pounds; the huge external tank (ET) that feeds the liquid hydrogen fuel and liquid oxygen oxidizer to the three main engines; and the two solid rocket boosters (SRB's), with their combined thrust of some 5.8 million pounds, that provide most of the power for the first two minutes of flight. Crucially involved with the Space Shuttle program virtually from its inception, the Marshall Space Flight Center (MSFC) played a leading role in the design, development, testing, and fabrication of many major Shuttle propulsion components. The MSFC was assigned responsibility for developing the Shuttle orbiter's high-performance main engines, the most complex rocket engines ever built. The MSFC was also responsible for developing the Shuttle's massive ET and the solid rocket motors and boosters.

  3. Space Shuttle Vehicle Illustration (United States)


    The Space Shuttle represented an entirely new generation of space vehicle, the world's first reusable spacecraft. Unlike earlier expendable rockets, the Shuttle was designed to be launched over and over again and would serve as a system for ferrying payloads and persornel to and from Earth orbit. The Shuttle's major components are the orbiter spacecraft; the three main engines, with a combined thrust of more than 1.2 million pounds; the huge external tank (ET) that feeds the liquid hydrogen fuel and liquid oxygen oxidizer to the three main engines; and the two solid rocket boosters (SRB's), with their combined thrust of some 5.8 million pounds. The SRB's provide most of the power for the first two minutes of flight. Crucially involved with the Space Shuttle program virtually from its inception, the Marshall Space Flight Center (MSFC) played a leading role in the design, development, testing, and fabrication of many major Shuttle propulsion components. The MSFC was assigned responsibility for developing the Shuttle orbiter's high-performance main engines, the most complex rocket engines ever built. The MSFC was also responsible for developing the Shuttle's massive ET and the solid rocket motors and boosters.

  4. Space Shuttle Drawing (United States)


    The Apollo program demonstrated that men could travel into space, perform useful tasks there, and return safely to Earth. But space had to be more accessible. This led to the development of the Space Shuttle. The Shuttle's major components are the orbiter spacecraft; the three main engines, with a combined thrust of more than 1.2 million pounds; the huge external tank (ET) that feeds the liquid hydrogen fuel and liquid oxygen oxidizer to the three main engines; and the two solid rocket boosters (SRBs), with their combined thrust of some 5.8 million pounds, that provide most of the power for the first two minutes of flight. Crucially involved with the Space Shuttle program virtually from its inception, the Marshall Space Flight Center (MSFC) played a leading role in the design, development, testing, and fabrication of many major Shuttle propulsion components.

  5. The design and development of two-failure tolerant mechanisms for the Spaceborne Imaging Radar (SIR-B) antenna (United States)

    Presas, S. J.


    The performance requirements, design constraints, and design qualification status of the mechanisms necessary to restrain, deploy, and stow the Spaceborne Imaging Radar (SIR) B antenna experiment on the Shuttle Orbiters are described.

  6. Space Radar Image of Taipei, Taiwan (United States)


    The northern end of the island country of Taiwan, including the capital city of Taipei, is shown in this spaceborne radar image. Taipei is the bright blue and red area in the lower center of the image. A portion of the city sits on an island surrounded by the Keelung and Freshwater Rivers. The main channel of the Freshwater River is to the right of the island and appears dark in the image. The channel to the left of the island is no longer active and appear slighter. Rugged, heavily vegetated mountains surround the city and are shown in green. The runways of the Chiang Kai Shek International Airport are seen as dark parallel strips in the upper left of the image. 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 10, 1994. The image is 50 kilometers by 33 kilometers (31 miles by 20 miles) and is centered at 25.1 degrees north latitude, 121.5 degrees east longitude. North is toward the upper right. 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 program.

  7. The proposed flatland radar (United States)

    Green, J. L.; Gage, K. S.; Vanzandt, T. E.; Nastrom, G. D.


    A flexible very high frequency (VHF) stratosphere-troposphere (ST) radar configured for meteorological research is to be constructed near Urbana, Illinois. Measurement of small vertical velocities associated with synoptic-scale meteorology can be performed. A large Doppler microwave radar (CHILL) is located a few km from the site of the proposed ST radar. Since the microwave radar can measure the location and velocity of hydrometeors and the VHF ST radar can measure clear (or cloudy) air velocities, simultaneous observations by these two radars of stratiform or convective weather systems would provide valuable meteorological information.

  8. Adaptive radar resource management

    CERN Document Server

    Moo, Peter


    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

  9. Radar and ARPA manual

    CERN Document Server

    Bole, A G


    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

  10. Space Radar Image of Wenatchee, Washington (United States)


    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. Analysis of the accuracy of Shuttle Radar Topography Mission (SRTM)

    Indian Academy of Sciences (India)

    ngeles. Chile. –37.3386. –71.5319. 745.40. 745.40. 734. 0.00. 11.40. 12. 15. Arequipa. P eru. –16.4656. –71.4927. 2488.92. 2493.56. 2489. –4.64. –0.08. 13. 16. Arti. Russia. 56.4297. 58.5606. 247.51. 242.20. 237. 5.31. 10.51. 14. 17. P ago. P ago. USA. –14.3261. –170.7220. 53.70. 47.17 x. 6 .53 x. 15. 18. Whangaparaoa.

  12. Analysis of the accuracy of Shuttle Radar Topography Mission (SRTM)

    Indian Academy of Sciences (India)

    istration (NASA), the German Aerospace Center. (DLR) and the Italian Space Agency (ASI) for three-dimensional digital mapping of the globe. (Van Zyl 2001). The main objective of the SRTM project was to collect near-global topographic data with absolute horizontal and vertical accuracies better than 20 and 16 m, ...

  13. NASA Shuttle Radar Topography Mission Swath Image Data V003 (United States)

    National Aeronautics and Space Administration — The NASA SRTM data sets result from a collaborative effort by the National Aeronautics and Space Administration (NASA) and the National Geospatial-Intelligence...

  14. Transformation of Shuttle Radar Topography Mission (SRTM) Digital ...

    African Journals Online (AJOL)

    Determination of height information using the classical field surveying and geodetic methods is rather expensive, rigorous and time consuming. It is also limited in the capacity of the earth surface data gathered. These conventional topographic mapping technologies have produced maps with a variety of scales and of ...

  15. Analysis of the accuracy of Shuttle Radar Topography Mission (SRTM)

    Indian Academy of Sciences (India)

    Africa, Australia and North America comply with the SRTM mission absolute vertical accuracy of 16 m. (with 90% confidence)/RMSE ∼10 m. However .... Group for International Agricul- ture Research Consortium for Spatial Information ... SRTM data should directly impact the result. Hence, it is important to understand the ...

  16. Novel radar techniques and applications

    CERN Document Server

    Klemm, Richard; Lombardo, Pierfrancesco; Nickel, Ulrich


    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.

  17. Principles of modern radar systems

    CERN Document Server

    Carpentier, Michel H


    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.

  18. Weather Radar Impact Zones (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...

  19. Radar Weather Observation (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...

  20. Noise Radar Technology Basics

    National Research Council Canada - National Science Library

    Thayaparan, T; Wernik, C


    .... In this report, the basic theory of noise radar design is treated. The theory supports the use of noise waveforms for radar detection and imaging in such applications as covert military surveillance and reconnaissance...

  1. Laser contouring of Space Shuttle tiles (United States)

    Bishop, P. J.; Minardi, A.; He, Mingli; Shelton, Bret

    Straight through and partial cuts were made in fibrous silicon-based ceramic insulation materials (used on the Space Shuttle) to determine the feasibility of laser machining. Experimental results were accumulated from over 800 exposures to determine the belt conditions for cutting. Laser intensity, feedrate, and other parameters were varied to determine conditions for cutting and are discussed in the paper.

  2. Radar return from a continuous vegetation canopy (United States)

    Bush, T. F.; Ulaby, F. T.


    The radar backscatter coefficient, sigma deg, of alfalfa was investigated as a function of both radar parameters and the physical characteristics of the alfalfa canopy. Measurements were acquired with an 8-18 GHz FM-CW mobile radar over an angular range of 0 - 70 deg as measured from nadir. The experimental data indicates that the excursions of sigma deg at nadir cover a range of nearly 18 dB during one complete growing cycle. An empirical model for sigma deg was developed which accounts for its variability in terms of soil moisture, plant moisture and plant height.

  3. Network radar countermeasure systems integrating radar and radar countermeasures

    CERN Document Server

    Jiang, Qiuxi


    This is the very first book to present the network radar countermeasure system. It explains in detail the systematic concept of combining radar and radar countermeasures from the perspective of the information acquisition of target location, the optimization of the reconnaissance and detection, the integrated attack of the signals and facilities, and technological and legal developments concerning the networked system. It achieves the integration of the initiative and passivity, detection and jamming. The book explains how the system locates targets, completes target identification, tracks targets and compiles the data.

  4. Space radar image of Mount Everest (United States)


    These are two comparison images of Mount Everest and its surroundings, along the border of Nepal and Tibet. The peak of Mount Everest, the highest elevation on Earth at 8,848 meters (29,028 feet), can be seen near the center of each image. The image at the top was acquired through thick cloud cover by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar (SIR-C/X-SAR) aboard the space shuttle Endeavour on April 16, 1994. The image on the bottom is an optical photograph taken by the Endeavour crew under clear conditions during the second flight of SIR-C/X-SAR on October 10, 1994. Both images show an area approximately 70 kilometers by 38 kilometers (43 miles by 24 miles) that is centered at 28.0 degrees north latitude and 86.9 degrees east longitude. North is toward the upper left. The colors in the radar image were obtained using the following radar channels: red represents the L-band (horizontally transmitted and received); green represents the L-band (horizontally transmitted and vertically received); blue represents the C-band (horizontally transmitted and vertically received). Radar illumination is from the top of the frame. The optical photograph has been geometrically adjusted to better match the area shown in the radar image. Many features of the Himalayan terrain are visible in both images. Snow covered areas appear white in the optical photograph while the same areas appear bright blue in the radar image. The radar image was taken in early spring and shows deep snow cover, while the optical photograph was taken in late summer and shows minimum snow cover. The curving and branching features seen in both images are glaciers. The two wavelengths and multiple polarizations of the SIR-C radar are sensitive to characteristics of the glacier surfaces that are not detected by conventional photography, such as the ice roughness, water content and stratification. For this reason, the glaciers show a variety of colors in the radar image (blue, purple, red

  5. Development of experimental concepts for investigating the strength behavior of fine-grained cohesive soil in the Spacelab/space shuttle zero-g environment (United States)

    Bonaparte, R.; Mitchell, J. K.


    Three different sets of tests are proposed for the NASA Spacelab experimental program. The first of tests, designed to measure the true cohesion of several different soils, would be carried out in space through use of a specially prepared direct shear apparatus. As part of this first series of tests, it is recommended that a set of drained unconfined compression tests be performed terrestrially on the same soils as tested in space. A form of the direct tension test is planned to measure the true tensile strength of the same types of soils used in the first series of tests. The direct tension tests could be performed terrestrially. The combined results of the direct shear tests, direct tension tests, and unconfined compression tests can be used to construct approximate failure envelopes for the soils tested in the region of the stress origin. Relationships between true cohesion and true tensile strength can also be investigated. In addition, the role of physio-chemical variables should be studied. The third set of tests involves using a multiaxial cubical or true triaxial test apparatus to investigate the influence of gravity induced fabric anisotropy and stress nonhomogeneities on the stress strain behavior of cohesive soils at low effective stress levels. These tests would involve both in space and terrestrial laboratory testing.

  6. Nanoparticle shuttle memory (United States)

    Zettl, Alex Karlwalter [Kensington, CA


    A device for storing data using nanoparticle shuttle memory having a nanotube. The nanotube has a first end and a second end. A first electrode is electrically connected to the first end of the nanotube. A second electrode is electrically connected to the second end of the nanotube. The nanotube has an enclosed nanoparticle shuttle. A switched voltage source is electrically connected to the first electrode and the second electrode, whereby a voltage may be controllably applied across the nanotube. A resistance meter is also connected to the first electrode and the second electrode, whereby the electrical resistance across the nanotube can be determined.

  7. Pulse Doppler radar

    CERN Document Server

    Alabaster, Clive


    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. Understanding radar systems

    CERN Document Server

    Kingsley, Simon


    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.

  9. Mobile Christian - shuttle flight (United States)


    Erin Whittle, 14, (seated) and Brianna Johnson, 14, look on as Louis Stork, 13, attempts a simulated landing of a space shuttle at StenniSphere. The young people were part of a group from Mobile Christian School in Mobile, Ala., that visited StenniSphere on April 21.

  10. Dipole magnet shuttle system

    International Nuclear Information System (INIS)

    Zinszer, A.; Pidcoe, S.; Spann, K.


    A transport system has been developed to move major magnet subassemblies between tool stations. The need existed to find a more efficient solution than overhead cranes to handle large parts. The argument against overhead cranes includes safety concerns, work disruption, particulate contamination and meeting the assembly rate requirements of ten magnets per day. The shuttle transport system represents a major effort of coordination between the various tool suppliers and General Dynamics to design a universal device capable of bridging the gap from single wound coils to a complete CDM. Effort was directed to systematically minimize material handling and related equipment by interfacing a completed assembly directly into the next work station or tool without losing its orientation or changing pickup points. The shuttle transport system is made up of a common transport device which can automatically go to any preprogrammed address on the factory floor. Each station has unique attachment tooling which can interface with the shuttle and the next assembly station. The shuttle can also circulate attachment tools back to their point of origin. Additional benefits of this system include inherent part protection, flow control, reduced banking or inventory, and potential for automatic control

  11. Space Radar Image of Central Sumatra, Indonesia (United States)


    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.

  12. EA Shuttle Document Retention Effort (United States)

    Wagner, Howard A.


    This slide presentation reviews the effort of code EA at Johnson Space Center (JSC) to identify and acquire databases and documents from the space shuttle program that are adjudged important for retention after the retirement of the space shuttle.

  13. Space Radar Image of Randonia Rain Cell (United States)


    Aperture Radar (SIR-C/X-SAR) on April 10, 1994 onboard 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.

  14. Space Radar Image of Athens, Greece (United States)


    This space radar image of Athens, Greece, shows the sprawling, modern development of this ancient capital city. Densely populated urban areas appear in shades of pink and light green. The Acropolis the dark green triangular patch in the center of the image. Archaeological discoveries indicate Athens has been continuously occupied for at least the last 5,000 years. Numerous ships, shown as bright dots, are seen in the harbor areas in the upper left part of the image. The port city of Piraeus is at the left center. This image is 45 kilometers by 45 kilometers (28 miles by 28 miles) and is centered at 37.9 degrees north latitude, 23.7 degrees east longitude. North is toward the upper right. The colors are assigned to different radar frequencies and polarizations are as follows: red is L-band, horizontally transmitted and received; green is L-band, horizontally transmitted and vertically received; and blue is C-band, horizontally transmitted and received. The image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar (SIR-C/X-SAR) on October 2, 1994 onboard the space shuttle Endeavour. 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.

  15. Space Radar Image of Bahia (United States)


    This is a color composite image of southern Bahia, Brazil, centered at 15.22 degree south latitude and 39.07 degrees west longitude. The image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar aboard the space shuttle Endeavour on its 38th orbit of Earth on October 2, 1994. The image covers an area centered over the Una Biological Reserve, one the largest protected areas in northeastern Brazil. The 7,000-hectare reserve is administered by the Brazilian Institute for the Environment and is part of the larger Atlantic coastal forest, a narrow band of rain forest extending along the eastern coast of Brazil. The Atlantic coastal forest of southern Bahia is one of the world's most threatened and diverse ecosystems. Due to widespread settlement, only 2 to 5 percent of the original forest cover remains. Yet the region still contains an astounding variety of plants and animals, including a large number of endemic species. More than half of the region's tree species and 80 percent of its animal species are indigenous and found nowhere else on Earth. The Una Reserve is also the only federally protected habitat for the golden-headed lion tamarin, the yellow-breasted capuchin monkey and many other endangered species. In the past few years, scientists from Brazilian and international conservation organizations have coordinated efforts to study the biological diversity of this region and to develop practical and economically viable options for preserving the remaining primary forests in southern Bahia. The shuttle imaging radar is used in this study to identify various land uses and vegetation types, including remaining patches of primary forest, cabruca forest (cacao planted in the understory of the native forest), secondary forest, pasture and coastal mangrove. Standard remote-sensing technology that relies on light reflected from the forest canopy cannot accurately distinguish between cabruca and undisturbed forest. Optical remote sensing is also

  16. Planetary Radars Operating Centre PROC (United States)

    Catallo, C.; Flamini, E.; Seu, R.; Alberti, G.


    an operative experimental platform, where a specific payload ( to be developed by the Italian Industry) a GPR will be accommodated on-board the Italian Space Agency stratospheric balloon and the data analysed by PROC; as a minimum two flight campaigns over polar regions are foreseen. The system shall be capable of acquiring radar data upon scientists requests in order to help them refine their models, experiment new algorithms, improve data interpretation capabilities. The paper also describes how the system will be integrated in the PROC, sharing the operational resources and aiding scientists to increase their knowledge in the field of surface radar sounding. A specific PROC Web facility is foreseen to allow data gathering, request submission, data exchange and dissemination.

  17. Use of Seasat satellite radar imagery for the detection of standing water beneath forest vegetation (United States)

    Macdonald, H. C.; Waite, W. P.; Demarcke, J. S.


    The Seasat synthetic aperture radar, operating at a 23-cm, L-band wavelength, detected anomalous tonal patterns in areas having relatively uniform vegetable canopy. These anomalously high radar returns were shown to be related more to the underlying terrain (areas of standing water) than to the vegetation canopy. These results show that L-band radars, imaging forested terrain in a Seasat configuration, are sensitive to gross changes in vegetation, and may even penetrate the vegetation canopy, providing an unmistakable radar signature. Properly designed space imaging radar shuttle experiments, using multiple frequency and polarization radars of various depression angles, may provide documentation for a flood-monitoring capability. Height, configuration, and density of the biomass in conjunction with frequency and incidence angle of the imaging system are shown to be important factors in formulating a backscatter model, but the relative significance of each is yet to be determined.

  18. Shuttle freezer conceptual design (United States)

    Proctor, B. W.; Russell, D. J.


    A conceptual design for a kit freezer for operation onboard shuttle was developed. The freezer features a self-contained unit which can be mounted in the orbiter crew compartment and is capable of storing food at launch and returning with medical samples. Packaging schemes were investigated to provide the optimum storage capacity with a minimum weight and volume penalty. Several types of refrigeration systems were evaluated to select one which would offer the most efficient performance and lowest hazard of safety to the crew. Detailed performance data on the selected, Stirling cycle principled refrigeration unit were developed to validate the feasibility of its application to this freezer. Thermal analyses were performed to determine the adequacy of the thermal insulation to maintain the desired storage temperature with the design cooling capacity. Stress analyses were made to insure the design structure integrity could be maintained over the shuttle flight regime. A proposed prototype freezer development plan is presented.

  19. Shuttle Topography Data Inform Solar Power Analysis (United States)


    The next time you flip on a light switch, there s a chance that you could be benefitting from data originally acquired during the Space Shuttle Program. An effort spearheaded by Jet Propulsion Laboratory (JPL) and the National Geospatial-Intelligence Agency (NGA) in 2000 put together the first near-global elevation map of the Earth ever assembled, which has found use in everything from 3D terrain maps to models that inform solar power production. For the project, called the Shuttle Radar Topography Mission (SRTM), engineers at JPL designed a 60-meter mast that was fitted onto Shuttle Endeavour. Once deployed in space, an antenna attached to the end of the mast worked in combination with another antenna on the shuttle to simultaneously collect data from two perspectives. Just as having two eyes makes depth perception possible, the SRTM data sets could be combined to form an accurate picture of the Earth s surface elevations, the first hight-detail, near-global elevation map ever assembled. What made SRTM unique was not just its surface mapping capabilities but the completeness of the data it acquired. Over the course of 11 days, the shuttle orbited the Earth nearly 180 times, covering everything between the 60deg north and 54deg south latitudes, or roughly 80 percent of the world s total landmass. Of that targeted land area, 95 percent was mapped at least twice, and 24 percent was mapped at least four times. Following several years of processing, NASA released the data to the public in partnership with NGA. Robert Crippen, a member of the SRTM science team, says that the data have proven useful in a variety of fields. "Satellites have produced vast amounts of remote sensing data, which over the years have been mostly two-dimensional. But the Earth s surface is three-dimensional. Detailed topographic data give us the means to visualize and analyze remote sensing data in their natural three-dimensional structure, facilitating a greater understanding of the features

  20. Phased-array radar design application of radar fundamentals

    CERN Document Server

    Jeffrey, Thomas


    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.

  1. ALT space shuttle barometric altimeter altitude analysis (United States)

    Killen, R.


    The accuracy was analyzed of the barometric altimeters onboard the space shuttle orbiter. Altitude estimates from the air data systems including the operational instrumentation and the developmental flight instrumentation were obtained for each of the approach and landing test flights. By comparing the barometric altitude estimates to altitudes derived from radar tracking data filtered through a Kalman filter and fully corrected for atmospheric refraction, the errors in the barometric altitudes were shown to be 4 to 5 percent of the Kalman altitudes. By comparing the altitude determined from the true atmosphere derived from weather balloon data to the altitude determined from the U.S. Standard Atmosphere of 1962, it was determined that the assumption of the Standard Atmosphere equations contributes roughly 75 percent of the total error in the baro estimates. After correcting the barometric altitude estimates using an average summer model atmosphere computed for the average latitude of the space shuttle landing sites, the residual error in the altitude estimates was reduced to less than 373 feet. This corresponds to an error of less than 1.5 percent for altitudes above 4000 feet for all flights.

  2. Doppler radar physiological sensing

    CERN Document Server

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


    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.

  3. Radar Signature Calculation Facility (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...

  4. Radar Plan Position Indicator Scope (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...

  5. Space radar image of New York City (United States)


    This radar image of the New York city metropolitan area. The island of Manhattan appears in the center of the image. The green-colored rectangle on Manhattan is Central Park. This image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar (SIR-C/ X-SAR) aboard the space shuttle Endeavour on October 10, 1994. North is toward the upper right. The area shown is 75.0 kilometers by 48.8 kilometers (46.5 miles by 30.2 miles). The image is centered at 40.7 degrees north latitude and 73.8 degrees west longitude. In general, light blue areas correspond to dense urban development, green areas to moderately vegetated zones and black areas to bodies of water. The Hudson River is the black strip that runs from the left edge to the upper right corner of the image. It separates New Jersey, in the upper left of the image, from New York. The Atlantic Ocean is at the bottom of the image where two barrier islands along the southern shore of Long Island are also visible. John F. Kennedy International Airport is visible above these islands. Long Island Sound, separating Long Island from Connecticut, is the dark area right of the center of the image. Many bridges are visible in the image, including the Verrazano Narrows, George Washington and Brooklyn bridges. The radar illumination is from the left of the image; this causes some urban zones to appear red because the streets are at a perpendicular angle to the radar pulse. 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). Radar images like this one could be used as a tool for city planners and resource managers to map and monitor land use patterns. The radar imaging systems can clearly detect the variety of landscapes in the area, as well as the density of urban

  6. Combined radar and telemetry system

    Energy Technology Data Exchange (ETDEWEB)

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


    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.

  7. Ultralight Radar for Small and Micro-Uav Navigation (United States)

    Scannapieco, A. F.; Renga, A.; Fasano, G.; Moccia, A.


    This paper presents a radar approach to navigation of small and micro Unmanned Aerial Vehicles (UAV) in environments challenging for common sensors. A technique based on radar odometry is briefly explained and schemes for complete integration with other sensors are proposed. The focus of the paper is set on ultralight radars and interpretation of outputs of such sensor when dealing with autonomous navigation in complex scenario. The experimental setup used to analyse the proposed approach comprises one multi-rotor UAV and one ultralight commercial radar. Results from flight tests in which both forward-only motion and mixed motion are presented and analysed, providing a reference for understanding outputs of radar in complex scenarios. The radar odometry solution is compared with ground truth provided by GPS sensor.


    Directory of Open Access Journals (Sweden)

    A. F. Scannapieco


    Full Text Available This paper presents a radar approach to navigation of small and micro Unmanned Aerial Vehicles (UAV in environments challenging for common sensors. A technique based on radar odometry is briefly explained and schemes for complete integration with other sensors are proposed. The focus of the paper is set on ultralight radars and interpretation of outputs of such sensor when dealing with autonomous navigation in complex scenario. The experimental setup used to analyse the proposed approach comprises one multi-rotor UAV and one ultralight commercial radar. Results from flight tests in which both forward-only motion and mixed motion are presented and analysed, providing a reference for understanding outputs of radar in complex scenarios. The radar odometry solution is compared with ground truth provided by GPS sensor.

  9. Space Radar Image of Tuva, Central Asia (United States)


    This spaceborne radar image shows part of the remote central Asian region of Tuva, an autonomous republic of the Russian Federation. Tuva is a mostly mountainous region that lies between western Mongolia and southern Siberia. This image shows the area just south of the republic's capital of Kyzyl. Most of the red, pink and blue areas in the image are agricultural fields of a large collective farming complex that was developed during the era of the Soviet Union. Traditional agricultural activity in the region, still active in remote areas, revolves around practices of nomadic livestock herding. White areas on the image are north-facing hillsides, which develop denser forests than south-facing slopes. The river in the upper right is one of the two major branches of the Yenesey River. Tuva has received some notoriety in recent years due to the intense interest of the celebrated Caltech physicist Dr. Richard Feynman, chronicled in the book 'Tuva or Bust' by Ralph Leighton. The image was acquired by Spaceborne Imaging Radar-C/X-Band SyntheticAperture Radar (SIR-C/X-SAR) onboard the space shuttle Endeavour onOctober 1, 1994. The image is 56 kilometers by 74 kilometers (35 miles by 46 miles) and is centered at 51.5 degrees north latitude, 95.1 degrees east longitude. North is toward the upper right. The colors are assigned to different radar fequencies and polarizations of the radar as follows: red is L-band, horizontally transmitted andreceived; green is L-band, horizontally transmitted and vertically received; and blue is C-band, horizontally transmitted and verticallyreceived. SIR-C/X-SAR, a joint mission of the German, Italian and United States space agencies, is part of NASA's Mission to PlanetEarth program.

  10. Microbiology studies in the Space Shuttle (United States)

    Taylor, G. R.


    Past space microbiology studies have evaluated three general areas: microbe detection in extraterrestrial materials; monitoring of autoflora and medically important species on crewmembers, equipment, and cabin air; and in vitro evaluations of isolated terrestrial species carried on manned and unmanned spaceflights. These areas are briefly reviewed to establish a basis for presenting probable experiment subjects applicable to the Space Shuttle era. Most extraterrestrial life detection studies involve visitations to other heavenly bodies. Although this is not applicable to the first series of Shuttle flights, attempts to capture meteors and spores in space could be important. Human pathogen and autoflora monitoring will become more important with increased variety among crewmembers. Inclusion of contaminated animal and plant specimens in the space lab will necessitate inflight evaluation of cross-contamination and infection potentials. The majority of Shuttle microbiology studies will doubtless fall into the third study area. Presence of a space lab will permit a whole range of experimentation under conditions similar to these experienced in earth-based laboratories. The recommendations of various study groups are analyzed, and probable inflight microbiological experiment areas are identified for the Life Sciences Shuttle Laboratory.

  11. Determination of radar MTF

    Energy Technology Data Exchange (ETDEWEB)

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


    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.

  12. MWR, Meteor Wind Radars (United States)

    Roper, R. G.


    The requirements of a state of the art meteor wind radar, and acceptable comprises in the interests of economy, are detailed. Design consideration of some existing and proposed radars are discussed. The need for international cooperation in mesopause level wind measurement, such as that being fostered by the MAP GLOBMET (Global Meteor Observations System) project, is emphasized.

  13. Quantum synthetic aperture radar (United States)

    Lanzagorta, Marco; Jitrik, Oliverio; Uhlmann, Jeffrey; Venegas-Andraca, Salvador E.


    Synthetic aperture radar (SAR) uses sensor motion to generate finer spatial resolution of a given target area. In this paper we explore the theoretical potential of quantum synthetic aperture quantum radar (QSAR). We provide theoretical analysis and simulation results which suggest that QSAR can provide improved detection performance over classical SAR in the high-noise low-brightness regime.

  14. Aspects of Radar Polarimetry


    LÜNEBURG, Ernst


    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.

  15. Hurricane Rita Track Radar Image with Topographic Overlay (United States)


    [figure removed for brevity, see original site] Animation About the animation: This simulated view of the potential effects of storm surge flooding on Galveston and portions of south Houston was generated with data from the Shuttle Radar Topography Mission. Although it is protected by a 17-foot sea wall against storm surges, flooding due to storm surges caused by major hurricanes remains a concern. The animation shows regions that, if unprotected, would be inundated with water. The animation depicts flooding in one-meter increments. About the image: The Gulf Coast from the Mississippi Delta through the Texas coast is shown in this satellite image from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) overlain with data from the Shuttle Radar Topography Mission (SRTM), and the predicted storm track for Hurricane Rita. The prediction from the National Weather Service was published Sept. 22 at 4 p.m. Central Time, and shows the expected track center in black with the lighter shaded area indicating the range of potential tracks the storm could take. Low-lying terrain along the coast has been highlighted using the SRTM elevation data, with areas within 15 feet of sea level shown in red, and within 30 feet in yellow. These areas are more at risk for flooding and the destructive effects of storm surge and high waves. Data used in this image were acquired by the Shuttle Radar Topography Mission aboard the Space Shuttle Endeavour, launched on Feb. 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 3-D measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter (approximately 200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Geospatial

  16. Equatorial MU Radar project (United States)

    Yamamoto, Mamoru; Hashiguchi, H.; Tsuda, Toshitaka; Yamamoto, Masayuki

    Research Institute for Sustainable Humanosphere, Kyoto University (RISH) has been studying the atmosphere by using radars. The first big facility was the MU (Middle and Upper atmosphere) radar installed in Shiga, Japan in 1984. This is one of the most powerful and multi-functional radar, and is successful of revealing importance of atmospheric waves for the dynamical vertical coupling processes. The next big radar was the Equatorial Atmosphere Radar (EAR) installed at Kototabang, West Sumatra, Indonesia in 2001. The EAR was operated under close collaboration with LAPAN (Indonesia National Institute for Aeronautics and Space), and conducted the long-term continuous observations of the equatorial atmosphere/ionosphere for more than 10 years. The MU radar and the EAR are both utilized for inter-university and international collaborative research program for long time. National Institute for Polar Research (NIPR) joined EISCAT Scientific Association together with Nagoya University, and developed the PANSY radar at Syowa base in Antarctica as a joint project with University of Tokyo. These are the efforts of radar study of the atmosphere/ionosphere in the polar region. Now we can find that Japan holds a global network of big atmospheric/ionospheric radars. The EAR has the limitation of lower sensitivity compared with the other big radars shown above. RISH now proposes a plan of Equatorial MU Radar (EMU) that is to establish the MU-radar class radar next to the EAR. The EMU will have an active phased array antenna with the 163m diameter and 1055 cross-element Yagis. Total output power of the EMU will be more than 500kW. The EMU can detect turbulent echoes from the mesosphere (60-80km). In the ionosphere incoherent-scatter observations of plasma density, drift, and temperature would be possible. Multi-channel receivers will realize radar-imaging observations. The EMU is one of the key facilities in the project "Study of coupling processes in the solar-terrestrial system

  17. Spaceborne weather radar (United States)

    Meneghini, Robert; Kozu, Toshiaki


    The present work on the development status of spaceborne weather radar systems and services discusses radar instrument complementarities, the current forms of equations for the characterization of such aspects of weather radar performance as surface and mirror-image returns, polarimetry, and Doppler considerations, and such essential factors in spaceborne weather radar design as frequency selection, scanning modes, and the application of SAR to rain detection. Attention is then given to radar signal absorption by the various atmospheric gases, rain drop size distribution and wind velocity determinations, and the characteristics of clouds, as well as the range of available estimation methods for backscattering, single- and dual-wavelength attenuation, and polarimetric and climatological characteristics.

  18. Intelligent radar data processing (United States)

    Holzbaur, Ulrich D.

    The application of artificial intelligence principles to the processing of radar signals is considered theoretically. The main capabilities required are learning and adaptation in a changing environment, processing and modeling information (especially dynamics and uncertainty), and decision-making based on all available information (taking its reliability into account). For the application to combat-aircraft radar systems, the tasks include the combination of data from different types of sensors, reacting to electronic counter-countermeasures, evaluation of how much data should be acquired (energy and radiation management), control of the radar, tracking, and identification. Also discussed are related uses such as monitoring the avionics systems, supporting pilot decisions with respect to the radar system, and general applications in radar-system R&D.

  19. Principles of modern radar radar applications

    CERN Document Server

    Scheer, James A


    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

  20. Quantum Shuttle in Phase Space

    DEFF Research Database (Denmark)

    Novotny, Tomas; Donarini, Andrea; Jauho, Antti-Pekka


    Abstract: We present a quantum theory of the shuttle instability in electronic transport through a nanostructure with a mechanical degree of freedom. A phase space formulation in terms of the Wigner function allows us to identify a crossover from the tunneling to the shuttling regime, thus...... extending the previously found classical results to the quantum domain. Further, a new dynamical regime is discovered, where the shuttling is driven exclusively by the quantum noise....

  1. Food packages for Space Shuttle (United States)

    Fohey, M. F.; Sauer, R. L.; Westover, J. B.; Rockafeller, E. F.


    The paper reviews food packaging techniques used in space flight missions and describes the system developed for the Space Shuttle. Attention is directed to bite-size food cubes used in Gemini, Gemini rehydratable food packages, Apollo spoon-bowl rehydratable packages, thermostabilized flex pouch for Apollo, tear-top commercial food cans used in Skylab, polyethylene beverage containers, Skylab rehydratable food package, Space Shuttle food package configuration, duck-bill septum rehydration device, and a drinking/dispensing nozzle for Space Shuttle liquids. Constraints and testing of packaging is considered, a comparison of food package materials is presented, and typical Shuttle foods and beverages are listed.

  2. Tabu search for target-radar assignment

    DEFF Research Database (Denmark)

    Hindsberger, Magnus; Vidal, Rene Victor Valqui


    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...

  3. Novel radar techniques and applications

    CERN Document Server

    Klemm, Richard; Koch, Wolfgang


    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.

  4. Space Radar Image of Chernobyl (United States)


    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

  5. Radar and electronic navigation

    CERN Document Server

    Sonnenberg, G J


    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

  6. Radar cross section

    CERN Document Server

    Knott, Gene; Tuley, Michael


    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

  7. Multispectral imaging radar (United States)

    Porcello, L. J.; Rendleman, R. A.


    A side-looking radar, installed in a C-46 aircraft, was modified to provide it with an initial multispectral imaging capability. The radar is capable of radiating at either of two wavelengths, these being approximately 3 cm and 30 cm, with either horizontal or vertical polarization on each wavelength. Both the horizontally- and vertically-polarized components of the reflected signal can be observed for each wavelength/polarization transmitter configuration. At present, two-wavelength observation of a terrain region can be accomplished within the same day, but not with truly simultaneous observation on both wavelengths. A multiplex circuit to permit this simultaneous observation has been designed. A brief description of the modified radar system and its operating parameters is presented. Emphasis is then placed on initial flight test data and preliminary interpretation. Some considerations pertinent to the calibration of such radars are presented in passing.

  8. Cognitive Nonlinear Radar (United States)


    filter, Bayesian decision theory, Generalized Likelihood Ratio Test (GLRT), and constant false alarm rate ( CFAR ) processing (31). Once the...Abbreviations, and Acronyms CFAR constant false alarm rate CNR cognitive nonlinear radar EM electromagnetic FCC Federal Communications Comission

  9. Telescience Data Collection Radar

    National Research Council Canada - National Science Library

    Beckner, Frederick


    Report developed under SBIR contract for topic AF99-258. The feasibility of developing a telescience data collection radar to reduce the cost of gathering aircraft signature data for noncooperative identification programs is investigated...

  10. Imaging Radar Polarimetry (United States)

    vanZyl, J. J.; Zebker, H. A.


    In this paper, we review the state of the art in imaging radar polarimetry, examine current developments in sensor technology and implementation for recording polarimetric measurements, and describe techniques and areas of application for the new remote sensing data.

  11. Wind Profiling Radar (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...

  12. Phased-array radars (United States)

    Brookner, E.


    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.

  13. A comparison of synthetic aperture radars applied for satellite remote sensing of the ocean surface

    Digital Repository Service at National Institute of Oceanography (India)

    Tilley, D.G.; Sarma, Y.V.B.

    imaging radar (SIR-B) aboard the space shuttle Challenger. The wave imaging capabilities of two more recent SAR systems, aboard the European ERS-1 and Russian Almaz satellites, over the Labrador Sea are observed in relation to an emerging consensus...

  14. San Gabriel Mountains, California, Radar image, color as height (United States)


    This topographic radar image shows the relationship of the urban area of Pasadena, California to the natural contours of the land. The image includes the alluvial plain on which Pasadena and the Jet Propulsion Laboratory sit, and the steep range of the San Gabriel Mountains. The mountain front and the arcuate valley running from upper left to the lower right are active fault zones, along which the mountains are rising. The chaparral-covered slopes above Pasadena are also a prime area for wildfires and mudslides. Hazards from earthquakes, floods and fires are intimately related to the topography in this area. Topographic data and other remote sensing images provide valuable information for assessing and mitigating the natural hazards for cities along the front of active mountain ranges.This image combines two types of data from the Shuttle Radar Topography Mission. The image brightness corresponds to the strength of the radar signal reflected from the ground, while colors show the elevation as measured by SRTM. Colors range from blue at the lowest elevations to white at the highest elevations. This image contains about 2300 meters (7500 feet) of total relief. White speckles on the face of some of the mountains are holes in the data caused by steep terrain. These will be filled using coverage from an intersecting pass.The Shuttle Radar Topography Mission (SRTM), launched on February 11,2000, uses 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. The mission is 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, an additional C-band imaging antenna 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) and the

  15. Single Frequency Network Based Distributed Passive Radar Technology

    Directory of Open Access Journals (Sweden)

    Wan Xian-rong


    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.

  16. Space Radar Image of Flevoland, Netherlands (United States)


    This is a three-frequency false color image of Flevoland, The Netherlands, centered at 52.4 degrees north latitude, 5.4 degrees east longitude. This image was acquired by the Spaceborne Imaging Radar-C and X-Band Synthetic Aperture Radar (SIR-C/X-SAR) aboard space shuttle Endeavour on April 14, 1994. It was produced by combining data from the X-band, C-band and L-band radars. The area shown is approximately 25 kilometers by 28 kilometers (15-1/2 by 17-1/2 miles). Flevoland, which fills the lower two-thirds of the image, is a very flat area that is made up of reclaimed land that is used for agriculture and forestry. At the top of the image, across the canal from Flevoland, is an older forest shown in red; the city of Harderwijk is shown in white on the shore of the canal. At this time of the year, the agricultural fields are bare soil, and they show up in this image in blue. The changes in the brightness of the blue areas are equal to the changes in roughness. The dark blue areas are water and the small dots in the canal are boats. This SIR-C/X-SAR supersite is being used for both calibration and agricultural studies. Several soil and crop ground-truth studies will be conducted during the shuttle flight. In addition, about 10calibration devices and 10 corner reflectors have been deployed to calibrate and monitor the radar signal. One of these transponders can be seen as a bright star in the lower right quadrant of the image. This false-color image was made using L-band total power in the red channel, C-band total power in the green channel, and X-band VV polarization in the blue channel. 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

  17. Fine resolution topographic mapping of the Jovian moons: a Ka-band high resolution topographic mapping interferometric synthetic aperture radar (United States)

    Madsen, Soren N.; Carsey, Frank D.; Turtle, Elizabeth P.


    The topographic data set obtained by MOLA has provided an unprecedented level of information about Mars' geologic features. The proposed flight of JIMO provides an opportunity to accomplish a similar mapping of and comparable scientific discovery for the Jovian moons through us of an interferometric imaging radar analogous to the Shuttle radar that recently generated a new topographic map of Earth. A Ka-band single pass across-track synthetic aperture radar (SAR) interferometer can provide very high resolution surface elevation maps. The concept would use two antennas mounted at the ends of a deployable boom (similar to the Shuttle Radar Topographic Mapper) extended orthogonal to the direction of flight. Assuming an orbit altitude of approximately 100 km and a ground velocity of approximately 1.5 km/sec, horizontal resolutions at the 10 meter level and vertical resolutions at the sub-meter level are possible.

  18. CAMEX-4 TOGA RADAR V1 (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...

  19. Short-range harmonic radar: chirp waveform, electronic targets (United States)

    Mazzaro, Gregory J.; Gallagher, Kyle A.; Martone, Anthony F.; Sherbondy, Kelly D.; Narayanan, Ram M.


    Radio-frequency (RF) electronic targets, such as man-portable electronics, cannot be detected by traditional linear radar because the radar cross section of those targets is much smaller than that of nearby clutter. One technology that is capable of separating RF electronic targets from naturally-occurring clutter is nonlinear radar. Presented in this paper is the evolution of nonlinear radar at the United States Army Research Laboratory (ARL) and recent results of short-range over-the-air harmonic radar tests there. For the present implementation of ARL's nonlinear radar, the transmit waveform is a chirp which sweeps one frequency at constant amplitude over an ultra-wide bandwidth (UWB). The receiver captures a single harmonic of this entire chirp. From the UWB received harmonic, a nonlinear frequency response of the radar environment is constructed. An inverse Fourier Transform of this nonlinear frequency response reveals the range to the nonlinear target within the environment. The chirped harmonic radar concept is validated experimentally using a wideband horn antenna and commercial off-the-shelf electronic targets.

  20. A Novel Monopulse Angle Estimation Method for Wideband LFM Radars

    Directory of Open Access Journals (Sweden)

    Yi-Xiong Zhang


    Full Text Available Traditional monopulse angle estimations are mainly based on phase comparison and amplitude comparison methods, which are commonly adopted in narrowband radars. In modern radar systems, wideband radars are becoming more and more important, while the angle estimation for wideband signals is little studied in previous works. As noise in wideband radars has larger bandwidth than narrowband radars, the challenge lies in the accumulation of energy from the high resolution range profile (HRRP of monopulse. In wideband radars, linear frequency modulated (LFM signals are frequently utilized. In this paper, we investigate the monopulse angle estimation problem for wideband LFM signals. To accumulate the energy of the received echo signals from different scatterers of a target, we propose utilizing a cross-correlation operation, which can achieve a good performance in low signal-to-noise ratio (SNR conditions. In the proposed algorithm, the problem of angle estimation is converted to estimating the frequency of the cross-correlation function (CCF. Experimental results demonstrate the similar performance of the proposed algorithm compared with the traditional amplitude comparison method. It means that the proposed method for angle estimation can be adopted. When adopting the proposed method, future radars may only need wideband signals for both tracking and imaging, which can greatly increase the data rate and strengthen the capability of anti-jamming. More importantly, the estimated angle will not become ambiguous under an arbitrary angle, which can significantly extend the estimated angle range in wideband radars.

  1. Space Shuttle mission: STS-67 (United States)


    The Space Shuttle Endeavor, scheduled to launch March 2, 1995 from NASA's Kennedy Space Center, will conduct NASA's longest Shuttle flight prior to date. The mission, designated STS-67, has a number of experiments and payloads, which the crew, commanded by Stephen S. Oswald, will have to oversee. This NASA press kit for the mission contains a general background (general press release, media services information, quick-look facts page, shuttle abort modes, summary timeline, payload and vehicle weights, orbital summary, and crew responsibilities); cargo bay payloads and activities (Astro 2, Get Away Special Experiments); in-cabin payloads (Commercial Minimum Descent Altitude Instrumentation Technology Associates Experiments, protein crystal growth experiments, Middeck Active Control Experiment, and Shuttle Amateur Radio Experiment); and the STS-67 crew biographies. The payloads and experiments are described and summarized to give an overview of the goals, objectives, apparatuses, procedures, sponsoring parties, and the assigned crew members to carry out the tasks.

  2. Influence of the vertical profile of reflectivity on radar-estimated rain rates at short time steps

    NARCIS (Netherlands)

    Berne, A.D.; Delrieu, G.; Andrieu, H.; Creutin, J.D.


    The present study aims to demonstrate the major influence of the vertical heterogeneity of rainfall on radar rain gauge assessment. For this purpose, an experimental setup was deployed during the HYDROMET Integrated Radar Experiment (HIRE-98) based on a conventional S-band weather radar operating at

  3. Radar for tracer particles (United States)

    Ott, Felix; Herminghaus, Stephan; Huang, Kai


    We introduce a radar system capable of tracking a 5 mm spherical target continuously in three dimensions. The 10 GHz (X-band) radar system has a transmission power of 1 W and operates in the near field of the horn antennae. By comparing the phase shift of the electromagnetic wave traveling through the free space with an IQ-mixer, we obtain the relative movement of the target with respect to the antennae. From the azimuth and inclination angles of the receiving antennae obtained in the calibration, we reconstruct the target trajectory in a three-dimensional Cartesian system. Finally, we test the tracking algorithm with target moving in circular as well as in pendulum motions and discuss the capability of the radar system.

  4. Radar Scan Methods in Modern Multifunctional Radars

    Directory of Open Access Journals (Sweden)

    V. N. Skosyrev


    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

  5. Target Detection and Ranging through Lossy Media using Chaotic Radar

    Directory of Open Access Journals (Sweden)

    Bingjie Wang


    Full Text Available A chaotic radar system has been developed for through-wall detection and ranging of targets. The chaotic signal generated by an improved Colpitts oscillator is designed as a probe signal. Ranging to target is achieved by the cross-correlation between the time-delayed reflected return signal and the replica of the transmitted chaotic signal. In this paper, we explore the performance of the chaotic radar system for target detection and ranging through lossy media. Experimental results show that the designed chaotic radar has the advantages of high range resolution, unambiguous correlation profile, and can be used for through wall target detection and sensing.

  6. Radar Sensing for Intelligent Vehicles in Urban Environments. (United States)

    Reina, Giulio; Johnson, David; Underwood, James


    Radar overcomes the shortcomings of laser, stereovision, and sonar because it can operate successfully in dusty, foggy, blizzard-blinding, and poorly lit scenarios. This paper presents a novel method for ground and obstacle segmentation based on radar sensing. The algorithm operates directly in the sensor frame, without the need for a separate synchronised navigation source, calibration parameters describing the location of the radar in the vehicle frame, or the geometric restrictions made in the previous main method in the field. Experimental results are presented in various urban scenarios to validate this approach, showing its potential applicability for advanced driving assistance systems and autonomous vehicle operations.

  7. Comet Radar Explorer (United States)

    Asphaug, Erik; CORE Science Team


    Comet Radar Explorer (CORE) is a low cost mission that uses sounding radar to image the 3D internal structure of the nucleus of Jupiter-family comet (JFC) Tempel 2. Believed to originate in the Kuiper Belt, JFCs are among the most primitive bodies in the inner solar system. CORE operates a 5 and 15 MHz Radar Reflection Imager from close orbit about the nucleus of Tempel 2, obtaining a dense network of echoes that are used to map its interior dielectric contrasts to high resolution (ង m) and resolve the dielectric constants to  m throughout the 16x8x9 km nucleus. The resulting clear images of internal structure and composition reveal how the nucleus was formed and how it has evolved. Radiometric tracking of the spacecraft orbit results in an interior mass distribution that constrains the radar-based models of interior composition. High-resolution visible and infrared color images provide the surface and exterior boundary conditions for interior models and hypotheses. They present the geology and morphology of the nucleus surface at meter-scales, and also the time-evolving activity, structure and composition of the inner coma. By making deep connections from interior to exterior, the data CORE provides will answer fundamental questions about the earliest stages of planetesimal evolution and planet formation, and lay the foundation for a comet nucleus sample return mission. CORE is led by Prof. Erik Asphaug of the University of California, Santa Cruz and is managed by JPL. It benefits from key scientific and payload contributions by ASI and CNES. The international science team has been assembled on the basis of their key involvement in past and ongoing missions to comets, and in Mars radar missions, and for their expertise in radar data analysis.

  8. Application of Radar Data to Remote Sensing and Geographical Information Systems (United States)

    vanZyl, Jakob J.


    The field of synthetic aperture radar changed dramatically over the past decade with the operational introduction of advance radar techniques such as polarimetry and interferometry. Radar polarimetry became an operational research tool with the introduction of the NASA/JPL AIRSAR system in the early 1980's, and reached a climax with the two SIR-C/X-SAR flights on board the space shuttle Endeavour in April and October 1994. Radar interferometry received a tremendous boost when the airborne TOPSAR system was introduced in 1991 by NASA/JPL, and further when data from the European Space Agency ERS-1 radar satellite became routinely available in 1991. Several airborne interferometric SAR systems are either currently operational, or are about to be introduced. Radar interferometry is a technique that allows one to map the topography of an area automatically under all weather conditions, day or night. The real power of radar interferometry is that the images and digital elevation models are automatically geometrically resampled, and could be imported into GIS systems directly after suitable reformatting. When combined with polarimetry, a technique that uses polarization diversity to gather more information about the geophysical properties of the terrain, a very rich multi-layer data set is available to the remote sensing scientist. This talk will discuss the principles of radar interferometry and polarimetry with specific application to the automatic categorization of land cover. Examples will include images acquired with the NASA/JPL AIRSAR/TOPSAR system in Australia and elsewhere.

  9. Ground penetrating radar

    CERN Document Server

    Daniels, David J


    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

  10. Systems and Methods for Radar Data Communication (United States)

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


    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.

  11. STS-121: Discovery Space Shuttle Safety Improvements Briefing (United States)


    Steve Poulos, Space Shuttle Orbiter Projects Office Manager, and John Chapman, Space Shuttle External Tank Project Manager is shown in this STS-121 Space Shuttle Discovery safety improvements briefing. A graphic presentation of the gap filler installation is shown. The graphics include: 1) Protruding gap fillers during STS-114 mission; 2) STS-114 gap fillers removed on orbiter; 3) Gap filler installation prior to STS-114; 4) Post-STS-114 installation techniques; 5) Gap filler installation post STS-114; 6) Gap filler priority areas; 7) Discovery gap filler installation table and status for STS-121; 8) Damaged blanket on STS-114; 9) On-orbit photography and post-landing photography on STS-114; and 10) STS-114 insulation tiles. Poulos presents imagery that was obtained on STS-114. The imagery includes: 1) The Enhanced Launch Vehicle Imaging System (ELVIS); 2) Liquid oxygen external tank view; 3) Hand-held imagery of the external tank falling into the ocean; 4) ELVIS on STS-121, short, medium and long range camera configurations; 5) Radar capability on the ground at Kennedy Space Center, and 6) STS-121 aft external tank door tiles. Poulos says that STS-121 will have even more imagery than STS-114. John Chapman presents video animation of the external tank where modifications were made along with the ice frost ramps with extensions. Chapman explains these areas using an external tank model. Questions are then answered from the media.

  12. Shuttle Discovery Landing at Edwards (United States)


    The STS-29 Space Shuttle Discovery mission lands at NASA's then Ames-Dryden Flight Research Facility, Edwards AFB, California, early Saturday morning, 18 March 1989. Touchdown was at 6:35:49 a.m. PST and wheel stop was at 6:36:40 a.m. on runway 22. Controllers chose the concrete runway for the landing in order to make tests of braking and nosewheel steering. The STS-29 mission was very successful, completing the launch of a Tracking and Data Relay communications satellite, as well as a range of scientific experiments. Discovery's five-man crew was led by Commander Michael L. Coats, and included pilot John E. Blaha and mission specialists James P. Bagian, Robert C. Springer, and James F. Buchli. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout

  13. A Passive Multistatic CW Radar System using Geostationary Illuminators


    Thölert, Steffen; Hounam, David


    In this paper a new passive radar system using a geostationary TV satellite as an illuminator and ground-based receivers is presented. The system can be operated as a monostatic or multistatic radar and can be used for target detection or reflectivity measurements. Full polarimetric operation is possible. The measurement technique and the system hardware of an experimental system are described, particular attention being paid to the methods of signal synchronization. The results of experiment...

  14. Study of airborne science experiment management concepts for application to space shuttle. Volume 1: Executive summary (United States)

    Mulholland, D. R.; Reller, J. O., Jr.; Neel, C. B.; Haughney, L. C.


    The management concepts and operating procedures are documented as they apply to the planning of shuttle spacelab operations. Areas discussed include: airborne missions; formulation of missions; management procedures; experimenter involvement; experiment development and performance; data handling; safety procedures; and applications to shuttle spacelab planning. Characteristics of the airborne science experience are listed, and references and figures are included.

  15. Compressive CFAR Radar Processing

    NARCIS (Netherlands)

    Anitori, L.; Rossum, W.L. van; Otten, M.P.G.; Maleki, A.; Baraniuk, R.


    In this paper we investigate the performance of a combined Compressive Sensing (CS) Constant False Alarm Rate (CFAR) radar processor under different interference scenarios using both the Cell Averaging (CA) and Order Statistic (OS) CFAR detectors. Using the properties of the Complex Approximate

  16. Compressive CFAR radar detection

    NARCIS (Netherlands)

    Anitori, L.; Otten, M.P.G.; Rossum, W.L. van; Maleki, A.; Baraniuk, R.


    In this paper we develop the first Compressive Sensing (CS) adaptive radar detector. We propose three novel architectures and demonstrate how a classical Constant False Alarm Rate (CFAR) detector can be combined with ℓ1-norm minimization. Using asymptotic arguments and the Complex Approximate

  17. Metamaterial for Radar Frequencies (United States)


    capacitive coupling with adjacent patches, as shown in Figure 3. The via provides inductance to ground. Figure 3. (a) Planar LH distributed periodic...After [20]). The capacitance in the structure balances out the inductance present when the cylinder is placed in a square array. The metallic... RADAR FREQUENCIES by Szu Hau Tan September 2012 Thesis Advisor: David C. Jenn Second Reader: James Calusdian

  18. Minefield overwatch using moving target indicator radar (United States)

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


    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.

  19. Shuttle operations, maintenance, and safety. (United States)

    Beddingfield, S. T.


    Review of a systematic search for practical solutions in the areas of space shuttle cryogenics, flight operations, ground operations, and safety. The insulation of the main-propulsion hydrogen tanks for both booster and orbiter to prevent water condensation is considered, as well as the insulation of the orbiter's orbital cryogen tanks for ground storage. Two approaches to the feeding of cryogens are outlined - namely, an approach depending on a periodic axial force to settle propellants and refill the basket, and a method of continuous feed through a capillary network adjacent to the walls throughout the tank, the latter method being independent of vehicle thrust. The development of reliable cryogen components is discussed, and the results of studies of launch-abort problems, shuttle approach and landing techniques, and the tolerance of ?deconditioned' crew and passengers to shuttle reentry g-loads are cited.

  20. Changes to the shuttle circuits

    CERN Multimedia

    GS Department


    To fit with passengers expectation, there will be some changes to the shuttle circuits as from Monday 10 October. See details on (on line on 7 October). Circuit No. 5 is cancelled as circuit No. 1 also stops at Bldg. 33. In order to guarantee shorter travel times, circuit No. 1 will circulate on Meyrin site only and circuit No. 2, with departures from Bldg. 33 and 500, on Prévessin site only. Site Services Section

  1. Space Shuttle Main Propulsion System (United States)

    Wood, C. C.


    The Space Shuttle Main Propulsion System provides the impulse to transfer the reusable Orbiter of the Space Shuttle Transportation system and its payload from earth to earth orbit. Both cryogenic and solid rocket propulsion systems are utilized. The selected systems are characterized by (1) reusability wherever possible to reduce program cost, (2) design pressures, and other important design parameters, for the liquid propellant engine significantly higher than past programs for increased performance, and (3) advanced materials and manufacturing processes to withstand the extreme environments. The approaches for solution of these varied problems are emphasized.

  2. Eastern Sahara Geology from Orbital Radar: Potential Analog to Mars (United States)

    Farr, T. G.; Paillou, P.; Heggy, E.


    Much of the surface of Mars has been intensely reworked by aeolian processes and key evidence about the history of the Martian environment seems to be hidden beneath a widespread layer of debris (paleo lakes and rivers, faults, impact craters). In the same way, the recent geological and hydrological history of the eastern Sahara is still mainly hidden under large regions of wind-blown sand which represent a possible terrestrial analog to Mars. The subsurface geology there is generally invisible to optical remote sensing techniques, but radar images obtained from the Shuttle Imaging Radar (SIR) missions were able to penetrate the superficial sand layer to reveal parts of paleohydrological networks in southern Egypt.

  3. Radar Reflectivity and Specific Attenuation in Melting Layer measured with Ground-based Ka-Radar System (United States)

    Nakamura, Kenji; Kaneko, Yuki; Nakagawa, Katsuhiko; Furukawa, Kinji; Suzuki, Kenji


    The scattering/attenuation characteristics of Ka-band radiowaves are measured with a dual Ka-band radar system whichi has been developed by JAXA. The dual Ka-band radar system consists of two nearly identical Ka-band FM-CW radars, and the precipitation systems between two radars are observed in opposite directions. From this experiment, equivalent radar reflectivity (Ze) and specific attenuation (k) are simultaneously obtained. Since calculation of k includes double differences along the radio path, the result is sensitive to the experimental parameters. Parameter tunings in data analysis including small change of radar elevation angles, etc are applied. After the parameter tuning, the k and Ze are reasonably obtained for clear melting layers, where Ze has a shape of a shelf, and k had a peak at the shoulder of the shelf. The results are qualitatively consistent with ground-based particle measurements. The results are used to evaluate the scattering/attenuation assumptions in the dual-frequency precipitation radar (DPR) aboard the Global Precipitation Measurement (GPM) core satellite.

  4. Observations and modeling of fog by cloud radar and optical sensors


    Li, Y.; Hoogeboom, P.; Russchenberg, H.


    Fog is a significant factor affecting the public traffic because visibility is reduced to a large extent. Therefore the determination of optical visibility in fog from radar instruments has received much interest. To observe fog with radar, high frequency bands (millimeter waves) have the best option. A 35 GHz cloud radar at the Cabauw Experimental Site for Atmospheric Research in the Netherlands has been used to make fog measurements in the "fog mode". Meanwhile, in-situ visibility sensors (...

  5. Composite technology in radar equipment. Dopler Meteo radar reflector device

    Directory of Open Access Journals (Sweden)

    A. V. Shumov


    Full Text Available The article is devoted features of the application composite materials in radar technology for example adjustment of the development technology of the reflector antenna device DMRL-S - radar for monitoring meteorological conditions.Russian and foreign analogues DMRL-S are made of aluminum, which no longer meets modern requirements for strength and weight. Also aluminum reflectors are not temperature stable. Composite materials are characterized by higher values of specific characteristics: temporary resistance, endurance limit, stiffness, elastic modulus, and less prone to cracking. The use of such materials improves the strength, rigidity and durability.For the manufacture of the DMRL-C reflector used composite materials based on epoxy resins reinforced with fiberglass (both unidirectional and woven. To increase the rigidity and weight reflector is made in the form of three-layer sandwich fiberglass panels with honeycomb core variable height. Design work was carried out in a CAD Siemens NX8.0 / Unigraphics, through which was established mathematical model layered reflector, as well as all accessories used in the manufacture. With the program NX Nastran was held strength calculation and analysis of stiffness on the finite element method.After the manufacture of the product, we measured the standard deviation of the working surface of the reflector from the theoretical surface using a three-dimensional laser scanner. Measurements were made at different angular positions of the reflector, and when loading. It is shown that the maximum strain in the operating modes of operation across the surface of the product does not exceed 4%, which will provide the most accurate operation of the product in any position of the antenna system.As a result of this work reflector design was developed, created and verified by experimental data calculation model. Reflector antenna device of the DMRL-S was manufactured and tested. The reflector was made of reinforced

  6. Compound Radar Approach for Breast Imaging. (United States)

    Byrne, Dallan; Sarafianou, Mantalena; Craddock, Ian J


    Multistatic radar apertures record scattering at a number of receivers when the target is illuminated by a single transmitter, providing more scattering information than its monostatic counterpart per transmission angle. This paper considers the well-known problem of detecting tumor targets within breast phantoms using multistatic radar. To accurately image potentially cancerous targets size within the breast, a significant number of multistatic channels are required in order to adequately calibrate-out unwanted skin reflections, increase the immunity to clutter, and increase the dynamic range of a breast radar imaging system. However, increasing the density of antennas within a physical array is inevitably limited by the geometry of the antenna elements designed to operate with biological tissues at microwave frequencies. A novel compound imaging approach is presented to overcome these physical constraints and improve the imaging capabilities of a multistatic radar imaging modality for breast scanning applications. The number of transmit-receive (TX-RX) paths available for imaging are increased by performing a number of breast scans with varying array positions. A skin calibration method is presented to reduce the influence of skin reflections from each channel. Calibrated signals are applied to receive a beamforming method, compounding the data from each scan to produce a microwave radar breast profile. The proposed imaging method is evaluated with experimental data obtained from constructed phantoms of varying complexity, skin contour asymmetries, and challenging tumor positions and sizes. For each imaging scenario outlined in this study, the proposed compound imaging technique improves skin calibration, clearly detects small targets, and substantially reduces the level of undesirable clutter within the profile.

  7. Identification of human motion signature using airborne radar data (United States)

    McDonald, Michael; Damini, Anthony


    Data containing the radar signature of amoving person on the groundwere collected at ranges of up to 30 kmfroma moving airborne platform using the DRDC Ottawa X-bandWideband Experimental Airborne Radar (XWEAR). The human target radar echo returns were found to possess a characteristic amplitude modulated (AM) and frequency modulated (FM) signature which could be usefully characterized in terms of conventional AM and FM modulation parameters. Human detection performance after space time adaptive processing is frequently limited by false alarms arising from incomplete cancellation of large radar cross-section discretes during the whitening step. However, the clutter discretes possess different modulation characteristics from the human targets discussed above. The ability of pattern classification techniques to use this parameter measurement space to distinguish between human targets and clutter discretes is explored and preliminary results presented.

  8. An Online Multisensor Data Fusion Framework for Radar Emitter Classification

    Directory of Open Access Journals (Sweden)

    Dongqing Zhou


    Full Text Available Radar emitter classification is a special application of data clustering for classifying unknown radar emitters in airborne electronic support system. In this paper, a novel online multisensor data fusion framework is proposed for radar emitter classification under the background of network centric warfare. The framework is composed of local processing and multisensor fusion processing, from which the rough and precise classification results are obtained, respectively. What is more, the proposed algorithm does not need prior knowledge and training process; it can dynamically update the number of the clusters and the cluster centers when new pulses arrive. At last, the experimental results show that the proposed framework is an efficacious way to solve radar emitter classification problem in networked warfare.

  9. Double Lap Shear Testing of Coating-Modified Ice Adhesion to Specific Shuttle Component Surfaces

    National Research Council Canada - National Science Library

    Ferrick, M. G; Mulherin, Nathan D; Coutermarsh, Barry A; Durell, Glenn D; Curtis, Leslie A; St. Clair, Terry L; Weiser, Erik S; Cano, Roberto J; Smith, Trent M; Stevenson, Charles G; Martinez, Eloy C


    The goals of this experimental program were to optimize the effectiveness of an icephobic coating for use on several Space Shuttle surfaces, to evaluate the effects of adding an ultraviolet light absorber (UVA...

  10. Space Shuttle Propulsion System Reliability (United States)

    Welzyn, Ken; VanHooser, Katherine; Moore, Dennis; Wood, David


    This session includes the following sessions: (1) External Tank (ET) System Reliability and Lessons, (2) Space Shuttle Main Engine (SSME), Reliability Validated by a Million Seconds of Testing, (3) Reusable Solid Rocket Motor (RSRM) Reliability via Process Control, and (4) Solid Rocket Booster (SRB) Reliability via Acceptance and Testing.

  11. Compressive CFAR Radar Processing


    Anitori, Laura; Baraniuk, Richard; Maleki, Arian; Otten, Matern; van Rossum, Wim


    In this paper we investigate the performance of a combined Compressive Sensing (CS) Constant False Alarm Rate (CFAR) radar processor under different interference scenarios using both the Cell Averaging (CA) and Order Statistic (OS) CFAR detectors. Using the properties of the Complex Approximate Message Passing (CAMP) algorithm, we demonstrate that the behavior of the CFAR processor is independent of the combination with the non-linear recovery and therefore its performance can be predicted us...

  12. Comet radar explorer (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

  13. Radar gun hazards

    Energy Technology Data Exchange (ETDEWEB)


    Radar guns - hand-held units used by the law to nail speeders - have been in use since the early '60s. Now they've been accused of causing cancer. Police officers in several states have so far filed eight suits against the manufacturer, claiming that they have contracted rare forms of cancer, such as of the eyelid and the testicle, from frequent proximity to the devices. Spurred by concerns expressed by police groups, researchers at the Rochester Institute of Technology are conducting what they believe to be the first research of its kind in the nation. Last month psychologist John Violanti, an expert in policy psychology and health, sent out a one-page survey to 6,000 active and retired police officers in New York State, asking them about their health and their use of radar guns. Violanti says melanoma, leukemia, and lymph node cancer may be linked to these as well as other electromagnetic devices. The Food and Drug Administration earlier this year issued a warning about radar guns, telling users not to operate them closer than 6 inches from the body. But this may not be a sufficient safeguard since the instruments can give off crisscrossing wave emissions within a police vehicle. The survey will be used to help determine if it would be safer to mount the guns, which are currently either hand-held or mounted on dashboards, outside troopers' cars.

  14. Synthetic Aperture Radar Technology Conference, New Mexico State University, Las Cruces, N. Mex., March 8-10, 1978, Proceedings (United States)


    The following aspects of SAR development are discussed: calibration techniques, image simulation and interpretability, antennas, data processing, and system design. Papers are presented on such topics as a postlaunch calibration experiment for the Seasat-A SAR, computer simulation of an orbital SAR system, definition study of the Shuttle Imaging Radar, custom LSI circuits for spaceborne SAR processors, and random sampling adaptively focusing SAR.

  15. Detection of Weather Radar Clutter

    DEFF Research Database (Denmark)

    Bøvith, Thomas


    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...... and precipitating and non-precipitating clouds. Another method uses the difference in the motion field of clutter and precipitation measured between two radar images. Furthermore, the direction of the wind field extracted from a weather model is used. The third method uses information about the refractive index...

  16. A review of array radars (United States)

    Brookner, E.


    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.

  17. Tomographic Techniques for Radar Ice Sounding

    DEFF Research Database (Denmark)

    Nielsen, Ulrik

    challenge. This dissertation deals with tomographic techniques based on multiphase-center radars that represent state-of-the-art technology within thefield of ice sounding. The use of advanced tomographic processing forclutter suppression is investigated, which up to this point has beenlargely unexplored...... in the literature. The investigation also includes atheoretical study of beamforming and direction-of-arrival (DOA) estimationtechniques. In addition to the primary treatment of clutter suppression,additional novel applications of tomography are also explored. Based on an experimental multi-phase-center dataset...... discrimination of the desired bed return from strong surface clutter ispresented. The technique is applied to data from the channel of the challengingJakobshavn Glacier acquired with the Multi-channel CoherentiiiRadar Depth Sounder/Imager (MCoRDS/I), where it is shown how thetechnique can be used to close some...

  18. Feature Extraction in Radar Target Classification

    Directory of Open Access Journals (Sweden)

    Z. Kus


    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.

  19. Radar studies of bird migration (United States)

    Williams, T. C.; Williams, J. M.


    Observations of bird migration with NASA radars were made at Wallops Island, Va. Simultaneous observations were made at a number of radar sites in the North Atlantic Ocean in an effort to discover what happened to those birds that were observed leaving the coast of North America headed toward Bermuda, the Caribbean and South America. Transatlantic migration, utilizing observations from a large number of radars is discussed. Detailed studies of bird movements at Wallops Island are presented.

  20. Radar techniques using array antennas

    CERN Document Server

    Wirth, Wulf-Dieter


    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

  1. Remote monitoring by impulse radar


    Taghimohammadi, Ensieh


    This master thesis is centered on development of signal processing algorithms for an Ultra - Wideband (UWB) Radar system. The goal of signal processing algorithms is to identify components of radar received signal. Moreover, implementing algorithms for checking both static and moving objects, estimating the distance from an object, and tracking the moving object. In this thesis we use a new type of Novelda UWB radar for indoor applications. It consists of two compact directional UWB antennas ...

  2. Photonic based marine radar demonstrator


    Laghezza, Francesco; Scotti, Filippo; Ghelfi, Paolo; Bogoni, Antonella; Banchi, Luca; Malaspina, Vincenzo; Serafino, Giovanni


    This paper presents the results obtained during the field trial experiments of the first photonic-based radar system demonstrator, in a real maritime environment. The developed demonstrator exploits photonic technologies for both the generation and the detection of radar RF signals, allowing increased performance even in term of system flexibility. The photonic radar performance have been compared with a state of the art commercial system for maritime applications provide...

  3. Space Radar Image of Yellowstone Park, Wyoming (United States)


    These two radar images show the majestic Yellowstone National Park, Wyoming, the oldest national park in the United States and home to the world's most spectacular geysers and hot springs. The region supports large populations of grizzly bears, elk and bison. In 1988, the park was burned by one of the most widespread fires to occur in the northern Rocky Mountains in the last 50 years. Surveys indicated that 793,880 acres of land burned. Of that, 41 percent was burned forest, with tree canopies totally consumed by the fire; 35 percent was a combination of unburned, scorched and blackened trees; 13 percent was surface burn under an unburned canopy; 6 percent was non-forest burn; and 5 percent was undifferentiated burn. Six years later, the burned areas are still clearly visible in these false-color radar images obtained by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar on board the space shuttle Endeavour. The image at the left was obtained using the L-band radar channel, horizontally received and vertically transmitted, on the shuttle's 39th orbit on October 2, 1994. The area shown is 45 kilometers by 71 kilometers (28 miles by 44 miles) in size and centered at 44.6 degrees north latitude, 110.7 degrees west longitude. North is toward the top of the image (to the right). Most trees in this area are lodge pole pines at different stages of fire succession. Yellowstone Lake appears as a large dark feature at the bottom of the scene. At right is a map of the forest crown, showing its biomass, or amount of vegetation, which includes foliage and branches. The map was created by inverting SIR-C data and using in situ estimates of crown biomass gathered by the Yellowstone National Biological Survey. The map is displayed on a color scale from blue (rivers and lakes with no biomass) to brown (non-forest areas with crown biomass of less than 4 tons per hectare) to light brown (areas of canopy burn with biomass of between 4 and 12 tons per hectare). Yellow

  4. Reconfigurable L-Band Radar (United States)

    Rincon, Rafael F.


    The reconfigurable L-Band radar is an ongoing development at NASA/GSFC that exploits the capability inherently in phased array radar systems with a state-of-the-art data acquisition and real-time processor in order to enable multi-mode measurement techniques in a single radar architecture. The development leverages on the L-Band Imaging Scatterometer, a radar system designed for the development and testing of new radar techniques; and the custom-built DBSAR processor, a highly reconfigurable, high speed data acquisition and processing system. The radar modes currently implemented include scatterometer, synthetic aperture radar, and altimetry; and plans to add new modes such as radiometry and bi-static GNSS signals are being formulated. This development is aimed at enhancing the radar remote sensing capabilities for airborne and spaceborne applications in support of Earth Science and planetary exploration This paper describes the design of the radar and processor systems, explains the operational modes, and discusses preliminary measurements and future plans.

  5. Space Shuttle Main Engine (SSME) Options for the Future Shuttle (United States)

    Jue, Fred; Kuck, Fritz; McCool, Alex (Technical Monitor)


    The main engines for the Future Shuttle will focus on improved safety and operability. Performance enhancements may also be required for vehicle safety purposes to achieve more desirable abort scenarios. This paper discusses the potential improvements that will be considered for implementation into the Future Shuttle. Integrated engine and vehicle health management systems will achieve additional system-level reliability improvements over those currently in development. Advanced instrumentation for detecting leaks, analyzing component wear and degradation, and providing sophisticated operational data will be used for reliable engine control and scheduling maintenance operations. A new nozzle and main combustion chamber (MCC) will reduce failure probability by 50% and allow for higher thrust capability without requiring the entire engine to be redesigned. Turbopump improvements may range from minor component improvements to using 3rd-generation pumps built on the advanced concepts demonstrated by the Integrated Powerhead Development (IPD) program and the Space Launch Initiative (SLI) prototype engines.The main engines for the Future Shuttle will focus on improved safety and operability. Performance enhancements may also be required for vehicle safety purposes to achieve more desirable abort scenarios. This paper discusses the potential improvements that will be considered for implementation into the Future Shuttle. Integrated engine and vehicle health management systems will achieve additional system-level reliability improvements over those currently in development. Advanced instrumentation for detecting leaks, analyzing component wear and degradation, and providing sophisticated operational data will be used for reliable engine control and scheduling maintenance operations. A new nozzle and main combustion chamber (MCC) will reduce failure probability by 50% and allow for higher thrust capability without requiring the entire engine to be redesigned. Turbopump

  6. Results of experimental investigations to determine external tank protuberance loads using a 0.03-scale model of the Space Shuttle launch configuration (model 47-OTS) in the NASA/ARC unitary plan wind tunnel, volume 1 (United States)

    Houlihan, S. R.


    Data were obtained on a 3-percent model of the Space Shuttle launch vehicle in the NASA/Ames Research Center 11x11-foot and 9x7-foot Unitary Plan Wind Tunnels. This test series has been identified as IA190A/B and was conducted from 7 Feb. 1980 to 19 Feb. 1980 (IA190A) and from 17 March 1980 to 19 March 1980 and from 8 May 1980 to 30 May 1980 (IA190B). The primary test objective was to obtain structural loads on the following external tank protuberances: (1) LO2 feedline, (2) GO2 pressure line, (3) LO2 antigeyser line, (4) GH2 pressure line, (5) LH2 tank cable tray, (6) LO2 tank cable tray, (7) Bipod, (8) ET/SRB cable tray, and (9) Crossbeam/Orbiter cable tray. To fulfill these objectives the following steps were taken: (1) Eight 3-component balances were used to measure forces on various sections of 1 thru 6 above. (2) 315 pressure orifices were distributed over all 9 above items. The LO2 feedline was instrumented with 96 pressure taps and was rotated to four positions to yield 384 pressure measurements. The LO2 antigeyser line was instrumented with 64 pressure taps and was rotated to two positions to yield 128 pressure measurements. (3) Three Chrysler miniature flow direction probes were mounted on a traversing mechanism on the tank upper surface centerline to obtain flow field data between the forward and aft attach structures. (4) Schlieren photographs and ultraviolet flow photographs were taken at all test conditions. Data from each of the four test phases are presented.

  7. Results of Experimental Investigations to Determine External Tank Protuberance Loads Using a 0.03-Scale Model of the Space Shuttle Launch Configuration (Model 47-OTS) in the NASA/ARC Unitary Plan Wind Tunnel, Volume 2 (United States)

    Houlihan, S. R.


    Data were obtained on a 3-percent model of the Space Shuttle launch vehicle in the NASA/Ames Research Center 11x11-foot and 9x7-foot Unitary Plan Wind Tunnels. This test series has been identified as IA19OA/B and was conducted from 7 Feb. 1980 to 19 Feb. 1980 (IA19OA) and from 17 March 1980 to 19 March 1980 and from 8 May 1980 to 30 May 1980 (IA19OB). The primary test objective was to obtain structural loads on the following external tank protuberances: (1) LO2 feedline; (2) GO2 pressure line; (3) LO2 antigeyser line; (4) GH2 pressure line; (5) LH2 tank cable tray; (6) LO2 tank cable tray; (7) Bipod; (8) ET/SRB cable tray; and (9) Crossbeam/Orbiter cable tray. To fulfill these objectives the following steps were taken: Eight 3-component balances were used to measure forces on various sections of 1 thru 6 above; 315 pressure orifices were distributed over all 9 above items. The LO2 feedline was instrumented with 96 pressure taps and was rotated to four positions to yield 384 pressure measurements. The LO2 antigeyser line was instrumented with 64 pressure taps and was rotated to two positions to yield 128 pressure measurements; Three Chrysler miniature flow direction probes were mounted on a traversing mechanism on the tank upper surface centerline to obtain flow field data between the forward and aft attach structures; and Schlieren photographs and ultraviolet flow photographs were taken at all test conditions. Data from each of the four test phases are presented.

  8. Results of experimental investigations to determine external tank protuberance loads using a 0.03-scale model of the Space Shuttle launch configuration (model 47-OTS) in the NASA/ARC unitary plan wind tunnel, volume 1 (United States)

    Houlihan, S. R.


    Data were obtained on a 3-percent model of the Space Shuttle launch vehicle in the NASA/Ames Research Center 11x11-foot and 9x7-foot Unitary Plan Wind Tunnels. This test series has been identified as IA190A/B and was conducted from 7 Feb. 1980 to 19 Feb. 1980 (IA190A) and from 17 March 1980 to 19 March 1980 and from 8 May 1980 to 30 May 1980 (IA190B). The primary test objective was to obtain structural loads on the following external tank protuberances: (1) LO2 feedline, (2) GO2 pressure line, (3) LO2 antigeyser line, (4) GH2 pressure line, (5) LH2 tank cable tray, (6) LO2 tank cable tray, (7) Bipod, (8) ET/SRB cable tray, and (9) Crossbeam/Orbiter cable tray. To fulfill these objectives the following steps were taken: (1) Eight 3-component balances were used to measure forces on various sections of 1 thru 6 above. (2) 315 pressure orifices were distributed over all 9 above items. The LO2 feedline was instrumented with 96 pressure taps and was rotated to four positions to yield 384 pressure measurements. The LO2 antigeyser line was instrumented with 64 pressure taps and was rotated to two positions to yield 128 pressure measurements. (3) Three Chrysler miniature flow direction probes were mounted on a traversing mechanism on the tank upper surface centerline to obtain flow field data between the forward and aft attach structures. (4) Schlieren photographs and ultraviolet flow photographs were taken at all test conditions. Data from each of the four test phases are presented.

  9. Results of experimental investigations to determine external tank protuberance loads using a 0.03-scale model of the Space Shuttle launch configuration (Model 47-OTS) in the NASA/ARC unitary plan wind tunnel, volume 2 (United States)

    Houlihan, S. R.


    Data were obtained on a 3-percent model of the Space Shuttle launch vehicle in the NASA/Ames Research Center 11x11-foot and 9x7-foot Unitary Plan Wind Tunnels. This test series has been identified as IA19OA/B and was conducted from 7 Feb. 1980 to 19 Feb. 1980 (IA19OA) and from 17 March 1980 to 19 March 1980 and from 8 May 1980 to 30 May 1980 (IA19OB). The primary test objective was to obtain structural loads on the following external tank protuberances: (1) LO2 feedline; (2) GO2 pressure line; (3) LO2 antigeyser line; (4) GH2 pressure line; (5) LH2 tank cable tray; (6) LO2 tank cable tray; (7) Bipod; (8) ET/SRB cable tray; and (9) Crossbeam/Orbiter cable tray. To fulfill these objectives the following steps were taken: Eight 3-component balances were used to measure forces on various sections of 1 thru 6 above; 315 pressure orifices were distributed over all 9 above items. The LO2 feedline was instrumented with 96 pressure taps and was rotated to four positions to yield 384 pressure measurements. The LO2 antigeyser line was instrumented with 64 pressure taps and was rotated to two positions to yield 128 pressure measurements; Three Chrysler miniature flow direction probes were mounted on a traversing mechanism on the tank upper surface centerline to obtain flow field data between the forward and aft attach structures; and Schlieren photographs and ultraviolet flow photographs were taken at all test conditions. Data from each of the four test phases are presented.

  10. Space Radar Image of Giza Egypt - with enlargement (United States)


    This radar image shows the area west of the Nile River near Cairo, Egypt. The Nile River is the dark band along the right side of the image and it flows approximately due North from the bottom to the right. The boundary between dense urbanization and the desert can be clearly seen between the bright and dark areas in the center of the image. This boundary represents the approximate extent of yearly Nile flooding which played an important part in determining where people lived in ancient Egypt. This land usage pattern persists to this day. The pyramids at Giza appear as three bright triangles aligned with the image top just at the boundary of the urbanized area. They are also shown enlarged in the inset box in the top left of the image. The Great Pyramid of Khufu (Cheops in Greek) is the northern most of the three Giza pyramids. The side-looking radar illuminates the scene from the top, the two sides of the pyramids facing the radar reflect most of the energy back to the antenna and appear radar bright; the two sides away from the radar reflect less energy back and appear dark Two additional pyramids can be seen left of center in the lower portion of the image. The modern development in the desert on the left side of the image is the Sixth of October City, an area of factories and residences started by Anwar Sadat to relieve urban crowding. The image was taken on April 19, 1994 by the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) aboard the 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 on latitude 29.72 degrees North latitude and 30.83 degrees East longitude. The area shown is approximately 20 kilometers by 30 kilometers. 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 C

  11. Experiment for buried pipes by stepped FM-CW radar; Step shiki FM-CW radar ni yoru maisetsukan tansa jikken

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, K.; Ito, M. [Kawasaki Geological Engineering, Co. Ltd., Tokyo (Japan); Tanabe, K. [Central Research Institute of Electric Power Industry, Tokyo (Japan)


    The underground radar exploration is adopted to surveys of cavity under the road and buried pipes since the result of high resolution is obtained. However, the explorative depth of the radar is shallow, 2-3m in soil basement, and its applicable field has been limited. The continuous wave radar (FM-CW radar) was devised to get deeper explorative depth, but has been used for the geological structure survey such as the fault survey since it is lower in resolution as compared with the pulse radar. Therefore, to make use of characteristics of the continuous wave radar and enhance resolution in the shallow part, an experiment on buried pipes was conducted for the purpose of assessing and improving the FM-CW radar. In this processing, the wave form treatment used in the reflection method seismic survey was adopted for the radar survey. There are some problems, but it is effective to adopt the same algorithm to that used in the seismic survey to the radar exploration. The explorative depth was discussed from the damping rate of electromagnetic waves and dynamic range of facilities of the experimental site, and 7m was obtained. 5 figs., 1 tab.

  12. Space Radar Image of Colombian Volcano (United States)


    This is a radar image of a little known volcano in northern Colombia. The image was acquired on orbit 80 of space shuttle Endeavour on April 14, 1994, by the Spaceborne Imaging Radar C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR). The volcano near the center of the image is located at 5.6 degrees north latitude, 75.0 degrees west longitude, about 100 kilometers (65 miles) southeast of Medellin, Colombia. The conspicuous dark spot is a lake at the bottom of an approximately 3-kilometer-wide (1.9-mile) volcanic collapse depression or caldera. A cone-shaped peak on the bottom left (northeast rim) of the caldera appears to have been the source for a flow of material into the caldera. This is the northern-most known volcano in South America and because of its youthful appearance, should be considered dormant rather than extinct. The volcano's existence confirms a fracture zone proposed in 1985 as the northern boundary of volcanism in the Andes. The SIR-C/X-SAR image reveals another, older caldera further south in Colombia, along another proposed fracture zone. Although relatively conspicuous, these volcanoes have escaped widespread recognition because of frequent cloud cover that hinders remote sensing imaging in visible wavelengths. Four separate volcanoes in the Northern Andes nations ofColombia and Ecuador have been active during the last 10 years, killing more than 25,000 people, including scientists who were monitoring the volcanic activity. Detection and monitoring of volcanoes from space provides a safe way to investigate volcanism. The recognition of previously unknown volcanoes is important for hazard evaluations because a number of major eruptions this century have occurred at mountains that were not previously recognized as volcanoes. 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

  13. Space Radar Image of Bebedauro, Brazil, seasonal (United States)


    This is an X-band image showing seasonal changes at the hydrological test site of Bebedouro in Brazil. The image is centered at 9 degrees south latitude and 40.2 degrees west longitude. This image was acquired by the Spaceborne Imaging Radar-C and X-band Synthetic Aperture Radar (SIR-C/X-SAR) aboard the space shuttle Endeavour on April 10, 1994, during the first flight of the radar system, and on October 1, 1994, during the second mission. The swath width is approximately 16.5 kilometers (10.5 miles) wide. The image channels have the following color assignments: red represents data acquired on April 10; green represents data acquired on October 1; blue corresponds to the ratio of the two data sets. Agriculture plays an important economic and social role in Brazil. One of the major problems related to Brazilian agriculture is estimating the size of planting areas and their productivity. Due to cloud cover and the rainy season, which occurs from November through April, optical and infrared Earth observations are seldom used to survey the region. An additional goal of monitoring this region is to watch the floodplains of rivers like Rio Sao Francisco in order to determine suitable locations for additional agricultural fields. This area belongs to the semi-arid northeastern region of Brazil, where estimates have suggested that about 10 times more land could be used for agriculture, including some locations which could be used for irrigation projects. Monitoring of soil moisture during the important summer crop season is of high priority for the future development and productivity of this region. In April the area was covered with vegetation because of the moisture of the soil and only small differences could be seen in X-band data. In October the run-off channels of this hilly region stand out quite clearly because the greenish areas indicated much less soil moisture and water content in plants. Spaceborne Imaging Radar-C and X-band Synthetic Aperture Radar (SIR

  14. Broadview Radar Altimetry Toolbox (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


    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 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

  15. Space Shuttle Corrosion Protection Performance (United States)

    Curtis, Cris E.


    The reusable Manned Space Shuttle has been flying into Space and returning to earth for more than 25 years. The launch pad environment can be corrosive to metallic substrates and the Space Shuttles are exposed to this environment when preparing for launch. The Orbiter has been in service well past its design life of 10 years or 100 missions. As part of the aging vehicle assessment one question under evaluation is how the thermal protection system and aging protective coatings are performing to insure structural integrity. The assessment of this cost resources and time. The information is invaluable when minimizing risk to the safety of Astronauts and Vehicle. This paper will outline a strategic sampling plan and some operational improvements made by the Orbiter Structures team and Corrosion Control Review Board.

  16. Radar foundations for imaging and advanced concepts

    CERN Document Server

    Sullivan, Roger


    Through courses internally taught at IDA, Dr. Roger Sullivan has devised a book that brings readers fully up to speed on the most essential quantitave aspects of general radar in order to introduce study of the most exciting and relevant applications to radar imaging and advanced concepts: Synthetic Aperture Radar (4 chapters), Space-time Adaptive Processing, moving target indication (MTI), bistatic radar, low probability of intercept (LPI) radar, weather radar, and ground-penetrating radar. Whether you're a radar novice or experienced professional, this is an essential refer

  17. Space Radar Image of Orange County, California (annotated version) (United States)


    This spaceborne radar image of Orange County, Calif., shows the massive urbanization of this rapidly growing region located just south of Los Angeles. Orange County, sandwiched between rugged mountains and the Pacific Ocean, includes the communities of Anaheim, Santa Ana and Huntington Beach. Anaheim Stadium can be seen in the upper center of the image, as a small white ring to the right of a major freeway intersection. The large dark blue rectangular area in the upper left is the Seal Beach Naval Weapons Station and adjacent wildlife refuge. Runways of the El Toro Marine Air Station appear as a black 'x' near the center of the image. The large purple area to the left of the the Air Station and extending to the coast is the scar left by the Laguna wildfire of October 1993. The sparse vegetation left in the wake of the fire provides a weak source of radar echoes, making the burn areas distinctively dark in the image. Another large burn area, from the Ortega fire of 1993, is seen in the mountains in the lower right of the image. The image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar (SIR-C/X-SAR) onboard the space shuttle Endeavour on October 3, 1994. The image is centered at 33.7 degrees north latitude and 117.7 degrees west longitude. North is toward the upper right. The image shows an area 66.2 kilometers by 44.2 kilometers (41.0 miles by 27.4 miles). The colors are assigned todifferent 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 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 program.

  18. Compact, Pneumatically Actuated Filter Shuttle (United States)

    Leighy, Bradley D.


    A compact, pneumatically actuated filter shuttle has been invented to enable alternating imaging of a wind-tunnel model in two different spectral bands characteristic of the pressure and temperature responses of a pressure and temperature-sensitive paint. This filter shuttle could also be used in other settings in which there are requirements for alternating imaging in two spectral bands. Pneumatic actuation was chosen because of a need to exert control remotely (that is, from outside the wind tunnel) and because the power leads that would be needed for electrical actuation would pose an unacceptable hazard in the wind tunnel. The entire shuttle mechanism and its housing can be built relatively inexpensively [camera used for viewing the wind-tunnel model. The mechanism includes a pneumatic actuator connected to a linkage. The linkage converts the actuator stroke to a scissor-like motion that places one filter in front of the camera and the other filter out of the way. Optoelectronic sensors detect tabs on the sliding panels for verification of the proper positioning of the filters.

  19. Performance indicators modern surveillance radar

    NARCIS (Netherlands)

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


    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

  20. Behavior Subtraction applied to radar

    NARCIS (Netherlands)

    Rossum, W.L. van; Caro Cuenca, M.


    An algorithm developed for optical images has been applied to radar data. The algorithm, Behavior Subtraction, is based on capturing the dynamics of a scene and detecting anomalous behavior. The radar application is the detection of small surface targets at sea. The sea surface yields the expected

  1. Imaging with Synthetic Aperture Radar

    CERN Document Server

    Massonnet, Didier


    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.  

  2. Millimeter radar improves target identification (United States)

    McAulay, Alastair D.


    Recently developed millimeter wave radar has advantages for target identification over conventional microwave radar which typically use lower frequencies. We describe the pertinent features involved in the construction of the new millimeter wave radar, the pseudo-optical cavity source and the quasi-optical duplexer. The long wavelength relative to light allows the radar beam to penetrate through most weather because the wavelength is larger than the particle size for dust, drizzle rain, fog. Further the mm wave beam passes through an atmospheric transmission window that provides a dip in attenuation. The higher frequency than conventional radar provides higher Doppler frequencies, for example, than X-band radar. We show by simulation that small characteristic vibrations and slow turns of an aircraft become visible so that the Doppler signature improves identification. The higher frequency also reduces beam width, which increases transmit and receive antenna gains. For the same power the transmit beam extends to farther range and the increase in receive antenna gain increases signal to noise ratio for improved detection and identification. The narrower beam can also reduce clutter and reject other noise more readily. We show by simulation that the radar can be used at lower elevations over the sea than conventional radar.

  3. 100 years of radar

    CERN Document Server

    Galati, Gaspare


    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...

  4. Feasibility analysis of WDM links for radar applications

    Directory of Open Access Journals (Sweden)

    D. Meena


    Full Text Available Active phased array antennas enhances the performance of modern radars by using multiple low power transmit/receive modules in place of a high power transmitter in conventional radars. Fully distributed phased array radars demand the distribution of various signals in radio frequency (RF and digital domain for real time operation. This is normally achieved through complex and bulky coaxial distribution networks. In this work, we intend to tap the inherent advantages of fiber links with wavelength division multiplexed (WDM technology and a feasibility study to adapt these links for radar applications is carried out. This is done by analysing various parameters like amplitude, delay, frequency and phase variation response of various radar waveforms over WDM links. This also includes performance evaluation of non-linear frequency modulation (NLFM signals, known for better signal to noise ratio (SNR to specific side lobe levels. NLFM waveforms are further analysed using pulse compression (PC technique. Link evaluation is also carried out using a standard simulation environment and is then experimentally verified with other waveforms like RF continuous wave (CW, pulsed RF and digital signals. Synchronization signals are generated from this variable duty cycle digital signals during real time radar operation. During evaluation of digital signals, variable transient effects for different duty cycles are observed from an amplifier configuration. A suppression method is proposed to eliminate this transient effects. Further, the link delay response is investigated using different lengths of fiber spools. It can be inferred from the experimental results that WDM links are capable of handling various signals significant to radar applications.

  5. Comparação entre a Feição de Hidrografia Extraída de uma Imagem do Srtm (Shuttle Radar Topography Mission) e a Vetorizada pelo Módulo Arcscan/ Arcgis®: : Estudo de Caso para Fins de Análise Hidrológica na Bacia Hidrográfica do Rio Grande, Divisa entre os Estados de MG e SP


    Sady Júnior M. C. de Menezes; Thiago P. M. Soares; Vanessa Mendes Lana; Cleverson Alves de Lima; Fernando Soares de Oliveira; Claubert Wagner G. de Menezes; Carlos Antonio Alvares Soares Ribeiro; Vicente Paulo Soares


    O SRTM - Shutle Radar Topography Mission – é uma missão o qual gerou-se uma base topográfica digital de alta resolução. A SRTM consiste num sistema de radar especialmente modificado que voou a bordo do Endea-vour (ônibus espacial), em fevereiro de 2000. As imagens obtidas pelo SRTM garantiu amplas aplicações em estudos espaciais, uma vez que os processos de comunicação visual para a produção de cartografia de base e mapas de precisão da análise espacial foram utilizados. O present...

  6. Response of space shuttle insulation panels to acoustic noise pressure (United States)

    Vaicaitis, R.


    The response of reusable space shuttle insulation panels to random acoustic pressure fields are studied. The basic analytical approach in formulating the governing equations of motion uses a Rayleigh-Ritz technique. The input pressure field is modeled as a stationary Gaussian random process for which the cross-spectral density function is known empirically from experimental measurements. The response calculations are performed in both frequency and time domain.


    Vanzyl, J.


    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

  8. Synthetic aperture radar autofocus via semidefinite relaxation. (United States)

    Liu, Kuang-Hung; Wiesel, Ami; Munson, David C


    The autofocus problem in synthetic aperture radar imaging amounts to estimating unknown phase errors caused by unknown platform or target motion. At the heart of three state-of-the-art autofocus algorithms, namely, phase gradient autofocus, multichannel autofocus (MCA), and Fourier-domain multichannel autofocus (FMCA), is the solution of a constant modulus quadratic program (CMQP). Currently, these algorithms solve a CMQP by using an eigenvalue relaxation approach. We propose an alternative relaxation approach based on semidefinite programming, which has recently attracted considerable attention in other signal processing problems. Experimental results show that our proposed methods provide promising performance improvements for MCA and FMCA through an increase in computational complexity.

  9. Development of Antennas for Subsurface Radars within ACE

    DEFF Research Database (Denmark)

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


    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 o...

  10. Detecting and Quantifying Forest Change: The Potential of Existing C- and X-Band Radar Datasets.

    Directory of Open Access Journals (Sweden)

    Mihai A Tanase

    Full Text Available This paper evaluates the opportunity provided by global interferometric radar datasets for monitoring deforestation, degradation and forest regrowth in tropical and semi-arid environments. The paper describes an easy to implement method for detecting forest spatial changes and estimating their magnitude. The datasets were acquired within space-borne high spatial resolutions radar missions at near-global scales thus being significant for monitoring systems developed under the United Framework Convention on Climate Change (UNFCCC. The approach presented in this paper was tested in two areas located in Indonesia and Australia. Forest change estimation was based on differences between a reference dataset acquired in February 2000 by the Shuttle Radar Topography Mission (SRTM and TanDEM-X mission (TDM datasets acquired in 2011 and 2013. The synergy between SRTM and TDM datasets allowed not only identifying changes in forest extent but also estimating their magnitude with respect to the reference through variations in forest height.

  11. The use of radar for bathymetry assessment

    NARCIS (Netherlands)

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


    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

  12. Status and Prospects of Radar Polarimetry Techniques


    Wang Xuesong


    Radar polarimetry is an applied fundamental science field that is focused on understanding interaction processes between radar waves and targets and disclosing their mechanisms. Radar polarimetry has significant application prospects in the fields of microwave remote sensing, earth observation, meteorological measurement, battlefield reconnaissance, anti-interference, target recognition, and so on. This study briefly reviews the development history of radar polarization theory and technology....

  13. Radar signal analysis and processing using Matlab

    CERN Document Server

    Mahafza, Bassem R


    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.

  14. Seismic excitation by space shuttles (United States)

    Kanamori, H.; Mori, J.; Sturtevant, B.; Anderson, D.L.; Heaton, T.


    Shock waves generated by the space shuttles Columbia (August 13, 1989), Atlantis (April 11, 1991) and Discovery (September 18, 1991) on their return to Edwards Air Force Base, California, were recorded by TERRAscope (Caltech's broadband seismic network), the Caltech-U.S.G.S Southern California Seismic Network (SCSN), and the University of Southern California (USC) Los Angeles Basin Seismic Network. The spatial pattern of the arrival times exhibits hyperbolic shock fronts from which the path, velocity and altitude of the space shuttle could be determined. The shock wave was acoustically coupled to the ground, converted to a seismic wave, and recorded clearly at the broadband TERRAscope stations. The acoustic coupling occurred very differently depending on the conditions of the Earth's surface surrounding the station. For a seismic station located on hard bedrock, the shock wave (N wave) was clearly recorded with little distortion. Aside from the N wave, very little acoustic coupling of the shock wave energy to the ground occurred at these sites. The observed N wave record was used to estimate the overpressure of the shock wave accurately; a pressure change of 0.5 to 2.2 mbars was obtained. For a seismic station located close to the ocean or soft sedimentary basins, a significant amount of shock wave energy was transferred to the ground through acoustic coupling of the shock wave and the oceanic Rayleigh wave. A distinct topography such as a mountain range was found effective to couple the shock wave energy to the ground. Shock wave energy was also coupled to the ground very effectively through large man made structures such as high rise buildings and offshore oil drilling platforms. For the space shuttle Columbia, in particular, a distinct pulse having a period of about 2 to 3 seconds was observed, 12.5 s before the shock wave, with a broadband seismograph in Pasadena. This pulse was probably excited by the high rise buildings in downtown Los Angeles which were

  15. Space Shuttle and Hypersonic Entry (United States)

    Campbell, Charles H.; Gerstenmaier, William H.


    Fifty years of human spaceflight have been characterized by the aerospace operations of the Soyuz, of the Space Shuttle and, more recently, of the Shenzhou. The lessons learned of this past half decade are important and very significant. Particularly interesting is the scenario that is downstream from the retiring of the Space Shuttle. A number of initiatives are, in fact, emerging from in the aftermath of the decision to terminate the Shuttle program. What is more and more evident is that a new era is approaching: the era of the commercial usage and of the commercial exploitation of space. It is probably fair to say, that this is the likely one of the new frontiers of expansion of the world economy. To make a comparison, in the last 30 years our economies have been characterized by the digital technologies, with examples ranging from computers, to cellular phones, to the satellites themselves. Similarly, the next 30 years are likely to be characterized by an exponential increase of usage of extra atmospheric resources, as a result of more economic and efficient way to access space, with aerospace transportation becoming accessible to commercial investments. We are witnessing the first steps of the transportation of future generation that will drastically decrease travel time on our Planet, and significantly enlarge travel envelope including at least the low Earth orbits. The Steve Jobs or the Bill Gates of the past few decades are being replaced by the aggressive and enthusiastic energy of new entrepreneurs. It is also interesting to note that we are now focusing on the aerospace band, that lies on top of the aeronautical shell, and below the low Earth orbits. It would be a mistake to consider this as a known envelope based on the evidences of the flights of Soyuz, Shuttle and Shenzhou. Actually, our comprehension of the possible hypersonic flight regimes is bounded within really limited envelopes. The achievement of a full understanding of the hypersonic flight

  16. Under the Radar

    CERN Document Server

    Goss, WM


    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.

  17. Signal processing in noise waveform radar

    CERN Document Server

    Kulpa, Krzysztof


    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

  18. Air and spaceborne radar systems an introduction

    CERN Document Server

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


    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

  19. Space Radar Image of Safsaf, North Africa (United States)


    This is a false-color image of the uninhabited Safsaf Oasis in southern Egypt near the Egypt/Sudan border. It was produced from data obtained from the L-band and C-band radars that are part of the Spaceborne Imaging Radar C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) onboard space shuttle Endeavour on April 9, 1994. The image is centered at 22 degree north latitude, 29 degrees east longitude. It shows detailed structures of bedrock; the dark blue sinuous lines are braided channels that occupy part of an old broad river valley. On the ground and in optical photographs, this big valley and the channels in it are invisible because they are entirely covered by windblown sand. Some of these same channels were observed in SIR-A images in 1981. It is hypothesized that the large valley was carved by one of several ancient predecessor rivers that crossed this part of North Africa, flowing westward, tens of millions of years before the Nile River existed. The Nile flows north about 300 kilometers (200 miles) to the east. The small channels are younger, and probably formed during relatively wet climatic periods within the past few hundred thousand years. This image shows that the channels are in a river valley located in an area where U.S. Geological Survey geologists and archeologists discovered an unusual concentration of hand axes (stone tools) used by Early Man (Homo erectus) hundreds of thousands of years ago. The image clearly shows that in wetter times, the valley would have supported game animals and vegetation. Today, as a result of climate change, the area in uninhabited and lacks water except fora few scattered oases. This color composite image was produced from C-band and L-band horizontal polarization images. The C-band image was assigned red, the L-band (HH) polarization image is shown in green, and the ratio of these two images (LHH/CHH) appears in blue. The primary and composite colors on the image indicate the degree to which the C-band, H-band, their ratio

  20. Incoherent Scatter Radar User Workshop (United States)

    Richmond, A. D.


    The incoherent scatter radar technique has developed over the years into one of the most powerful tools for investigating physical processes in the upper atmosphere. The National Science Foundation (NSF) now supports a chain of four incoherent scatter facilities at Sondrestromfjord (Greenland), Millstone Hill (Massachusetts), Arecibo (Puerto Rico), and Jicamarca (PERU). Six European nations support the EISCAT facility in northern Scandinavia, and France also has a radar at St. Santin. Recently, the organizations reponsible for each of the six radars agreed to participate in a centralized data base being established at the National Center for Atmospheric Research (NCAR) to make their data more readily accessible to the scientific community at large.

  1. Introduction to radar target recognition

    CERN Document Server

    Tait, P


    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

  2. Environment-Adaptive Radar Techniques. (United States)


    as the mathematics and computer pro - grams are concer.ned we can now develop the design by considering one antenna searching a 2w/3 azimuth sector...Griffis Air Force am*, Now York 13441 8140-6 102 15~ VhAS xpg IAS bed XOWANO 00 the .WAC aU* Affsftz OffU. (PA) an4 to *elesseb). to 00e matsa b"oals Uast fdSRIIIV by bloti nobi Radar Automated Radar Design Adaptive Radar Environmental Sensor Blind Speed Avoidance S. AVISTRACT ’CauM....o

  3. Gyroklystron-Powered WARLOC Radar (United States)

    Danly, B. G.; Cheung, W. J.; Gregers-Hansen, V.; Linde, G.; Ngo, M.


    A high-power, coherent, W-band (94 GHz) millimeter-wave radar has been developed at the Naval Research Laboratory. This radar, named WARLOC, employs a 100 kW peak power, 10 kW average power gyro-klystron as the final power amplifier, an overmoded transmission line system, and a quasi-optical duplexer, together with a high gain antenna, four-channel receiver, and state-of-the-art signal processing. The gyro-amplifiers and the implementation in the WARLOC radar will be described.

  4. Material integrity verification radar

    International Nuclear Information System (INIS)

    Koppenjan, S.K.


    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

  5. Subsurface and through-wall SAR imaging techniques for ground penetrating radar

    Directory of Open Access Journals (Sweden)

    Unal M.


    Full Text Available This paper presents some useful signal processing and synthetic aperture radar imaging techniques for ultra-wide band (UWB ground penetrating radar. Novel UWB antenna structures are experimentally designed in this work. Raw and processed data collected in the course of experimental studies of subsurface sensing and through-wall imaging scenarios are demonstrated in B-scan and C-scan target images.

  6. Space Shuttle Usage of z/OS (United States)

    Green, Jan


    This viewgraph presentation gives a detailed description of the avionics associated with the Space Shuttle's data processing system and its usage of z/OS. The contents include: 1) Mission, Products, and Customers; 2) Facility Overview; 3) Shuttle Data Processing System; 4) Languages and Compilers; 5) Application Tools; 6) Shuttle Flight Software Simulator; 7) Software Development and Build Tools; and 8) Fun Facts and Acronyms.

  7. Optical fiber reach extended FMCW radar for remote respiratory tracking

    DEFF Research Database (Denmark)

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


    Wireless monitoring of human vital signs such as breathing rate is a nonintrusive alternative to contemporary solutions relying on physical contact. To ease the installment, fiber optical transmission is used to extend the reach from the transmitter and receiver circuitry to the antenna subsystem....... In this paper, a frequency modulated carrier wave radar, operating at 25.7–26.6 GHz and utilizing optical fiber extension, was experimentally demonstrated to accurately recover the breathing rate of a human placed 1 m away from the radar antennas....

  8. Design, Performance and Optimization for Multimodal Radar Operation

    Directory of Open Access Journals (Sweden)

    Surendra S. Bhat


    Full Text Available This paper describes the underlying methodology behind an adaptive multimodal radar sensor that is capable of progressively optimizing its range resolution depending upon the target scattering features. It consists of a test-bed that enables the generation of linear frequency modulated waveforms of various bandwidths. This paper discusses a theoretical approach to optimizing the bandwidth used by the multimodal radar. It also discusses the various experimental results obtained from measurement. The resolution predicted from theory agrees quite well with that obtained from experiments for different target arrangements.

  9. Design, Performance and Optimization for Multimodal Radar Operation (United States)

    Bhat, Surendra S.; Narayanan, Ram M.; Rangaswamy, Muralidhar


    This paper describes the underlying methodology behind an adaptive multimodal radar sensor that is capable of progressively optimizing its range resolution depending upon the target scattering features. It consists of a test-bed that enables the generation of linear frequency modulated waveforms of various bandwidths. This paper discusses a theoretical approach to optimizing the bandwidth used by the multimodal radar. It also discusses the various experimental results obtained from measurement. The resolution predicted from theory agrees quite well with that obtained from experiments for different target arrangements.


    McCauley, John F.; Breed, Carlos S.; Schaber, Gerald G.; McHugh, William P.; Issawi, Bahay; Haynes, C. Vance; Grolier, Maurice J.; El Kilani, Ali


    A complex history of Cenozoic fluvial activity in the presently hyperarid eastern Sahara is inferred from Shuttle Imaging Radar (SIR) data and postflight field investigations in southwest Egypt and northwest Sudan. SIR images were coregistered with Landsat and existing maps as a guide to exploration of the buried paleodrainages (radar rivers) first discovered by SIR-A. Field observations explain the radar responses of three types of radar rivers: RR-1, RR-2, and RR-3. A generalized model of the radar rivers, based on field studies and regional geologic relations, shows apparent changes in river regimen since the large valleys were established during the late Paleogene-early Neogene eras. SIR-based mapping of these paleodrainages, although incomplete, reveals missing links in an area once thought to be devoid of master streams.

  11. Bistatic radar system analysis and software development


    Teo, Ching Leong


    Approved for public release, distribution is unlimited Bistatic radar has some properties that are distinctly different from monostatic radar. Recently bistatic radar has received attention for its potential to detect stealth targets due to enhanced target forward scatter. Furthermore, the feasibility of hitchhiker radar has been demonstrated, which allows passive radar receivers to detect and track targets. This thesis developed a software simulation package in Matlab that provides a conv...

  12. Space Shuttle Main Engine Public Test Firing (United States)


    A new NASA Space Shuttle Main Engine (SSME) roars to the approval of more than 2,000 people who came to John C. Stennis Space Center in Hancock County, Miss., on July 25 for a flight-certification test of the SSME Block II configuration. The engine, a new and significantly upgraded shuttle engine, was delivered to NASA's Kennedy Space Center in Florida for use on future shuttle missions. Spectators were able to experience the 'shake, rattle and roar' of the engine, which ran for 520 seconds - the length of time it takes a shuttle to reach orbit.

  13. Fly eye radar or micro-radar sensor technology (United States)

    Molchanov, Pavlo; Asmolova, Olga


    To compensate for its eye's inability to point its eye at a target, the fly's eye consists of multiple angularly spaced sensors giving the fly the wide-area visual coverage it needs to detect and avoid the threats around him. Based on a similar concept a revolutionary new micro-radar sensor technology is proposed for detecting and tracking ground and/or airborne low profile low altitude targets in harsh urban environments. Distributed along a border or around a protected object (military facility and buildings, camp, stadium) small size, low power unattended radar sensors can be used for target detection and tracking, threat warning, pre-shot sniper protection and provides effective support for homeland security. In addition it can provide 3D recognition and targets classification due to its use of five orders more pulses than any scanning radar to each space point, by using few points of view, diversity signals and intelligent processing. The application of an array of directional antennas eliminates the need for a mechanical scanning antenna or phase processor. It radically decreases radar size and increases bearing accuracy several folds. The proposed micro-radar sensors can be easy connected to one or several operators by point-to-point invisible protected communication. The directional antennas have higher gain, can be multi-frequency and connected to a multi-functional network. Fly eye micro-radars are inexpensive, can be expendable and will reduce cost of defense.

  14. NASA's modified Boeing 747 Shuttle Carrier Aircraft with the Space Shuttle Endeavour on top lifts of (United States)


    NASA's modified Boeing 747 Shuttle Carrier Aircraft with the Space Shuttle Endeavour on top lifts off from Edwards Air Force Base to begin its ferry flight back to the Kennedy Space Center in Florida.

  15. Coherent Doppler Laser Radar: Technology Development and Applications (United States)

    Kavaya, Michael J.; Arnold, James E. (Technical Monitor)


    NASA's Marshall Space Flight Center has been investigating, developing, and applying coherent Doppler laser radar technology for over 30 years. These efforts have included the first wind measurement in 1967, the first airborne flights in 1972, the first airborne wind field mapping in 1981, and the first measurement of hurricane eyewall winds in 1998. A parallel effort at MSFC since 1982 has been the study, modeling and technology development for a space-based global wind measurement system. These endeavors to date have resulted in compact, robust, eyesafe lidars at 2 micron wavelength based on solid-state laser technology; in a factor of 6 volume reduction in near diffraction limited, space-qualifiable telescopes; in sophisticated airborne scanners with full platform motion subtraction; in local oscillator lasers capable of rapid tuning of 25 GHz for removal of relative laser radar to target velocities over a 25 km/s range; in performance prediction theory and simulations that have been validated experimentally; and in extensive field campaign experience. We have also begun efforts to dramatically improve the fundamental photon efficiency of the laser radar, to demonstrate advanced lower mass laser radar telescopes and scanners; to develop laser and laser radar system alignment maintenance technologies; and to greatly improve the electrical efficiency, cooling technique, and robustness of the pulsed laser. This coherent Doppler laser radar technology is suitable for high resolution, high accuracy wind mapping; for aerosol and cloud measurement; for Differential Absorption Lidar (DIAL) measurements of atmospheric and trace gases; for hard target range and velocity measurement; and for hard target vibration spectra measurement. It is also suitable for a number of aircraft operations applications such as clear air turbulence (CAT) detection; dangerous wind shear (microburst) detection; airspeed, angle of attack, and sideslip measurement; and fuel savings through

  16. MIMO Radar - Diversity Means Superiority

    National Research Council Canada - National Science Library

    Li, Jian


    We consider a multiple-input multiple-output (MIMO) radar system where both the transmitter and receiver have multiple well-separated subarrays with each subarray containing closely-spaced antennas...

  17. Moving Target Detection With Compact Laser Doppler Radar (United States)

    Sepp, G.; Breining, A.; Eisfeld, W.; Knopp, R.; Lill, E.; Wagner, D.


    This paper describes an experimental integrated optronic system for detection and tracking of moving objects. The system is based on a CO2 waveguide laser Doppler ra-dar with homodyne receiver and galvanometer mirror beam scanner. A "hot spot" seeker consisting of a thermal imager with image processor transmits the coordinates of IR-emitting, i.e. potentially powered, objects to the laser radar scanner. The scanner addresses these "hot" locations operating in a large field-of-view (FOV) random ac-cess mode. Hot spots exhibiting a Doppler shifted laser signal are indicated in the thermal image by velocity-to-colour encoded markers. After switching to a small FOV scanning mode, the laser Doppler radar is used to track fast moving objects. Labora-tory and field experiments with moving objects including rotating discs, automobiles and missiles are described.

  18. Radar Methods in Urban Environments (United States)


    Jointly optimal design for MIMO radar frequency-hopping waveforms using game theory,” IEEE Trans. on Aerospace and Electronic Systems, Vol. 52...appear in IEEE Trans. on Signal Processing. J9. J. Li and A. Nehorai, “Distributed particle filtering via optimal fusion of Gaussian mixtures ,” in...scatterers," IEEE Trans. Antennas Propag., Vol. 64, pp. 988-997, Mar. 2016. 28. K. Han and A. Nehorai, "Jointly optimal design for MIMO radar frequency

  19. Radar interferometry persistent scatterer technique

    CERN Document Server

    Kampes, Bert M


    This volume is devoted to the Persistent Scatterer Technique, the latest development in radar interferometric data processing. It is the only book on Permanent Scatterer (PS) technique of radar interferometry, and it details a newly developed stochastic model and estimator algorithm to cope with possible problems for the application of the PS technique. The STUN (spatio-temporal unwrapping network) algorithm, developed to cope with these issues in a robust way, is presented and applied to two test sites.

  20. Space Radar Image of Sakura-Jima Volcano, Japan (United States)


    The active volcano Sakura-Jima on the island of Kyushu, Japan is shown in the center of this radar image. The volcano occupies the peninsula in the center of Kagoshima Bay, which was formed by the explosion and collapse of an ancient predecessor of today's volcano. The volcano has been in near continuous eruption since 1955. Its explosions of ash and gas are closely monitored by local authorities due to the proximity of the city of Kagoshima across a narrow strait from the volcano's center, shown below and to the left of the central peninsula in this image. City residents have grown accustomed to clearing ash deposits from sidewalks, cars and buildings following Sakura-jima's eruptions. The volcano is one of 15 identified by scientists as potentially hazardous to local populations, as part of the international 'Decade Volcano' program. The image was acquired by the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) onboard the space shuttle Endeavour on October 9, 1994. 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 31.6 degrees North latitude and 130.6 degrees East longitude. North is toward the upper left. The area shown measures 37.5 kilometers by 46.5 kilometers (23.3 miles by 28.8 miles). The colors in the image are assigned to different frequencies and polarizations of the radar as follows: red is L-band vertically transmitted, vertically received; green is the average of L-band vertically transmitted, vertically received and C-band vertically transmitted, vertically received; blue is C-band vertically transmitted, vertically received.

  1. Wind turbine clutter mitigation in coastal UHF radar. (United States)

    Yang, Jing; Pan, Chao; Wang, Caijun; Jiang, Dapeng; Wen, Biyang


    Coastal UHF radar provides a unique capability to measure the sea surface dynamic parameters and detect small moving targets, by exploiting the low energy loss of electromagnetic waves propagating along the salty and good conducting ocean surface. It could compensate the blind zone of HF surface wave radar at close range and reach further distance than microwave radars. However, its performance is susceptible to wind turbines which are usually installed on the shore. The size of a wind turbine is much larger than the wavelength of radio waves at UHF band, which results in large radar cross section. Furthermore, the rotation of blades adds time-varying Doppler frequency to the clutter and makes the suppression difficult. This paper proposes a mitigation method which is based on the specific periodicity of wind turbine clutter and performed mainly in the time-frequency domain. Field experimental data of a newly developed UHF radar are used to verify this method, and the results prove its effectiveness.

  2. Wind Turbine Clutter Mitigation in Coastal UHF Radar

    Directory of Open Access Journals (Sweden)

    Jing Yang


    Full Text Available Coastal UHF radar provides a unique capability to measure the sea surface dynamic parameters and detect small moving targets, by exploiting the low energy loss of electromagnetic waves propagating along the salty and good conducting ocean surface. It could compensate the blind zone of HF surface wave radar at close range and reach further distance than microwave radars. However, its performance is susceptible to wind turbines which are usually installed on the shore. The size of a wind turbine is much larger than the wavelength of radio waves at UHF band, which results in large radar cross section. Furthermore, the rotation of blades adds time-varying Doppler frequency to the clutter and makes the suppression difficult. This paper proposes a mitigation method which is based on the specific periodicity of wind turbine clutter and performed mainly in the time-frequency domain. Field experimental data of a newly developed UHF radar are used to verify this method, and the results prove its effectiveness.

  3. SRTM Radar Image, Wrapped Color as Height/EarthKam Optical Honolulu, Hawaii (United States)


    These two images of the eastern part of the island of Oahu, Hawaii provide information on regional topography and show the relationship between urban development and sensitive ecosystems. On the left is a topographic radar image collected by the Shuttle Radar Topography Mission (SRTM.) On the right is an optical image acquired by a digital camera on the Space Shuttle Endeavour, which carried SRTM. Features of interest in this scene include Diamond Head (an extinct volcano at the lower center), Waikiki Beach (just left of Diamond Head), the Punchbowl National Cemetery (another extinct volcano, at the foot of the Koolau Mountains), downtown Honolulu and Honolulu airport (lower left of center), and Pearl Harbor (at the left edge.)The topography shows the steep, high central part of the island surrounded by flatter coastal areas. The optical image shows the urban areas and a darker, forested region on the mountain slopes. The clouds in the optical image and the black areas on the topographic image are both a result of the steep topography. In this tropical region, high mountain peaks are usually covered in clouds. These steep peaks also cause shadows in the radar data, resulting in missing data 'holes.' A second pass over the island was obtained by SRTM and will be used to fill in the holes.The left image combines two types of SRTM data. Brightness corresponds to the strength of the radar signal reflected from the ground, while colors show the elevation. Each color cycle (from pink through blue and back to pink) represents 400 meters (1,300 feet) of elevation difference, like the contour lines on a topographic map. This image contains about 2,400 meters (8,000 feet) of total relief. The optical image was acquired by the Shuttle Electronic Still Camera with a lens focal length of 64 millimeters (2.5 inches) for the Earth Knowledge Acquired by Middle school students (EarthKAM) project. EarthKAM has flown on five space shuttle missions since 1996. Additional information

  4. Shuttle Spacelab Core Equipment Freezer (United States)

    Copeland, R. J.


    This paper describes the preliminary design of a Shuttle Spacelab Core Equipment Freezer. The unit will provide the capability to freeze and store many experiment specimens. Two models of the unit are planned. One model provides storage at -70 C; the other model will provide -70 C storage, a freeze dry capability, storage at a selectable temperature in the range of 0 C to -70 C, and means of maintaining close temperature tolerances. In addition an exchanger loop will be available at 4 C for cooling of a centrifuge and a remote storage compartment. A test tube holder, a dish holder and thermal capacitors for rapid freezing of large specimens will also be provided. A Stirling Cycle was selected as the active refrigerator for minimum cost and weight.

  5. Shuttle onboard IMU alignment methods (United States)

    Henderson, D. M.


    The current approach to the shuttle IMU alignment is based solely on the Apollo Deterministic Method. This method is simple, fast, reliable and provides an accurate estimate for the present cluster to mean of 1,950 transformation matrix. If four or more star sightings are available, the application of least squares analysis can be utilized. The least squares method offers the next level of sophistication to the IMU alignment solution. The least squares method studied shows that a more accurate estimate for the misalignment angles is computed, and the IMU drift rates are a free by-product of the analysis. Core storage requirements are considerably more; estimated 20 to 30 times the core required for the Apollo Deterministic Method. The least squares method offers an intermediate solution utilizing as much data that is available without a complete statistical analysis as in Kalman filtering.

  6. San Andreas Fault, Southern California , Radar Image, Wrapped Color as Height (United States)


    This topographic radar image vividly displays California's famous San Andreas Fault along the southwestern edge of the Mojave Desert, 75 kilometers (46 miles) north of downtown Los Angeles. The entire segment of the fault shown in this image last ruptured during the Fort Tejon earthquake of 1857. This was one of the greatest earthquakes ever recorded in the U.S., and it left an amazing surface rupture scar over 350 kilometers in length along the San Andreas. Were the Fort Tejon shock to happen today, the damage would run into billions of dollars, and the loss of life would likely be substantial, as the communities of Wrightwood, Palmdale, and Lancaster (among others) all lie upon or near the 1857 rupture area. The Lancaster/Palmdale area appears as bright patches just below the center of the image and the San Gabriel Mountains fill the lower left half of the image. At the extreme lower left is Pasadena. High resolution topographic data such as these are used by geologists to study the role of active tectonics in shaping the landscape, and to produce earthquake hazard maps.This image combines two types of data from the Shuttle Radar Topography Mission. The image brightness corresponds to the strength of the radar signal reflected from the ground, while colors show the elevation as measured by SRTM. Each cycle of colors (from pink through blue back to pink) represents an equal amount of elevation difference (400 meters, or 1300 feet) similar to contour lines on a standard topographic map. This image contains about 2400 meters (8000 feet) of total relief.The Shuttle Radar Topography Mission (SRTM), launched on February 11,2000, uses 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. The mission is 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, an

  7. Liquid Hydrogen Consumption During Space Shuttle Program (United States)

    Partridge, Jonathan K.


    This slide presentation reviews the issue of liquid hydrogen consumption and the points of its loss in prior to the shuttle launch. It traces the movement of the fuel from the purchase to the on-board quantity and the loss that results in 54.6 of the purchased quantity being on board the Shuttle.

  8. Optimal Wafer Cutting in Shuttle Layout Problems

    DEFF Research Database (Denmark)

    Nisted, Lasse; Pisinger, David; Altman, Avri


    . The shuttle layout problem is frequently solved in two phases: first, a floorplan of the shuttle is generated. Then, a cutting plan is found which minimizes the overall number of wafers needed to satisfy the demand of each die type. Since some die types require special production technologies, only compatible...

  9. Shuttle valves and system for fluid control

    Energy Technology Data Exchange (ETDEWEB)

    Caralli, M. J.; Friedline, G. W.


    An apparatus system for drying gases to provide a reverse flow to and from a pair of absorbent beds is automatically solely controlled by a unitary inlet logic shuttle valve unit and by a unitary outlet logic shuttle valve unit. Each valve unit employs positive acting slide valve elements that operate in a smooth and effective manner.

  10. Shuttle valves and system for fluid control

    International Nuclear Information System (INIS)

    Caralli, M. J.; Friedline, G. W.


    An apparatus system for drying gases to provide a reverse flow to and from a pair of absorbent beds is automatically solely controlled by a unitary inlet logic shuttle valve unit and by a unitary outlet logic shuttle valve unit. Each valve unit employs positive acting slide valve elements that operate in a smooth and effective manner

  11. Space Shuttle RTOS Bayesian Network (United States)

    Morris, A. Terry; Beling, Peter A.


    With shrinking budgets and the requirements to increase reliability and operational life of the existing orbiter fleet, NASA has proposed various upgrades for the Space Shuttle that are consistent with national space policy. The cockpit avionics upgrade (CAU), a high priority item, has been selected as the next major upgrade. The primary functions of cockpit avionics include flight control, guidance and navigation, communication, and orbiter landing support. Secondary functions include the provision of operational services for non-avionics systems such as data handling for the payloads and caution and warning alerts to the crew. Recently, a process to selection the optimal commercial-off-the-shelf (COTS) real-time operating system (RTOS) for the CAU was conducted by United Space Alliance (USA) Corporation, which is a joint venture between Boeing and Lockheed Martin, the prime contractor for space shuttle operations. In order to independently assess the RTOS selection, NASA has used the Bayesian network-based scoring methodology described in this paper. Our two-stage methodology addresses the issue of RTOS acceptability by incorporating functional, performance and non-functional software measures related to reliability, interoperability, certifiability, efficiency, correctness, business, legal, product history, cost and life cycle. The first stage of the methodology involves obtaining scores for the various measures using a Bayesian network. The Bayesian network incorporates the causal relationships between the various and often competing measures of interest while also assisting the inherently complex decision analysis process with its ability to reason under uncertainty. The structure and selection of prior probabilities for the network is extracted from experts in the field of real-time operating systems. Scores for the various measures are computed using Bayesian probability. In the second stage, multi-criteria trade-off analyses are performed between the scores

  12. Space Shuttle Orbiter-Illustration (United States)


    This illustration is an orbiter cutaway view with callouts. The orbiter is both the brains and heart of the Space Transportation System (STS). About the same size and weight as a DC-9 aircraft, the orbiter contains the pressurized crew compartment (which can normally carry up to seven crew members), the huge cargo bay, and the three main engines mounted on its aft end. There are three levels to the crew cabin. Uppermost is the flight deck where the commander and the pilot control the mission. The middeck is where the gallery, toilet, sleep stations, and storage and experiment lockers are found for the basic needs of weightless daily living. Also located in the middeck is the airlock hatch into the cargo bay and space beyond. It is through this hatch and airlock that astronauts go to don their spacesuits and marned maneuvering units in preparation for extravehicular activities, more popularly known as spacewalks. The Space Shuttle's cargo bay is adaptable to hundreds of tasks. Large enough to accommodate a tour bus (60 x 15 feet or 18.3 x 4.6 meters), the cargo bay carries satellites, spacecraft, and spacelab scientific laboratories to and from Earth orbit. It is also a work station for astronauts to repair satellites, a foundation from which to erect space structures, and a hold for retrieved satellites to be returned to Earth. Thermal tile insulation and blankets (also known as the thermal protection system or TPS) cover the underbelly, bottom of the wings, and other heat-bearing surfaces of the orbiter to protect it during its fiery reentry into the Earth's atmosphere. The Shuttle's 24,000 individual tiles are made primarily of pure-sand silicate fibers, mixed with a ceramic binder. The solid rocket boosters (SRB's) are designed as an in-house Marshall Space Flight Center project, with United Space Boosters as the assembly and refurbishment contractor. The solid rocket motor (SRM) is provided by the Morton Thiokol Corporation.

  13. A Doppler Radar System for Sensing Physiological Parameters in Walking and Standing Positions

    Directory of Open Access Journals (Sweden)

    Malikeh Pour Ebrahim


    Full Text Available Doppler radar can be implemented for sensing physiological parameters wirelessly at a distance. Detecting respiration rate, an important human body parameter, is essential in a range of applications like emergency and military healthcare environments, and Doppler radar records actual chest motion. One challenge in using Doppler radar is being able to monitor several patients simultaneously and in different situations like standing, walking, or lying. This paper presents a complete transmitter-receiver Doppler radar system, which uses a 4 GHz continuous wave radar signal transmission and receiving system, to extract base-band data from a phase-shifted signal. This work reports experimental evaluations of the system for one and two subjects in various standing and walking positions. It provides a detailed signal analysis of various breathing rates of these two subjects simultaneously. These results will be useful in future medical monitoring applications.

  14. Shuttle Entry Imaging Using Infrared Thermography (United States)

    Horvath, Thomas; Berry, Scott; Alter, Stephen; Blanchard, Robert; Schwartz, Richard; Ross, Martin; Tack, Steve


    During the Columbia Accident Investigation, imaging teams supporting debris shedding analysis were hampered by poor entry image quality and the general lack of information on optical signatures associated with a nominal Shuttle entry. After the accident, recommendations were made to NASA management to develop and maintain a state-of-the-art imagery database for Shuttle engineering performance assessments and to improve entry imaging capability to support anomaly and contingency analysis during a mission. As a result, the Space Shuttle Program sponsored an observation campaign to qualitatively characterize a nominal Shuttle entry over the widest possible Mach number range. The initial objectives focused on an assessment of capability to identify/resolve debris liberated from the Shuttle during entry, characterization of potential anomalous events associated with RCS jet firings and unusual phenomenon associated with the plasma trail. The aeroheating technical community viewed the Space Shuttle Program sponsored activity as an opportunity to influence the observation objectives and incrementally demonstrate key elements of a quantitative spatially resolved temperature measurement capability over a series of flights. One long-term desire of the Shuttle engineering community is to calibrate boundary layer transition prediction methodologies that are presently part of the Shuttle damage assessment process using flight data provided by a controlled Shuttle flight experiment. Quantitative global imaging may offer a complementary method of data collection to more traditional methods such as surface thermocouples. This paper reviews the process used by the engineering community to influence data collection methods and analysis of global infrared images of the Shuttle obtained during hypersonic entry. Emphasis is placed upon airborne imaging assets sponsored by the Shuttle program during Return to Flight. Visual and IR entry imagery were obtained with available airborne

  15. Optical synthetic aperture radar (United States)

    Ilovitsh, Asaf; Zach, Shlomo; Zalevsky, Zeev


    A method is proposed for increasing the resolution of an object and overcoming the diffraction limit of an optical system installed on top of a moving imaging system, such as an airborne platform or satellite. The resolution improvement is obtained via a two-step process. First, three low resolution differently defocused images are captured and the optical phase is retrieved using an improved iterative Gershberg-Saxton based algorithm. The phase retrieval allows numerical back propagation of the field to the aperture plane. Second, the imaging system is shifted and the first step is repeated. The obtained optical fields at the aperture plane are combined and a synthetically increased lens aperture is generated along the direction of movement, yielding higher imaging resolution. The method resembles a well-known approach from the microwave regime called the synthetic aperture radar in which the antenna size is synthetically increased along the platform propagation direction. The proposed method is demonstrated via Matlab simulation as well as through laboratory experiment.

  16. Space Radar Image of Prince Albert, Canada (United States)


    This is a false-color composite of Prince Albert, Canada, centered at 53.91 north latitude and 104.69 west longitude. This image was acquired by the Spaceborne Imaging Radar C/X-Band Synthetic Aperture Radar(SIR-C/X-SAR) aboard space shuttle Endeavour on its 20th orbit. The area is located 40 kilometers (25 miles) north and 30 kilometers (20 miles) east of the town of Prince Albert in the Saskatchewan province of Canada. The image covers the area east of the Candle lake, between gravel surface highways 120 and 106 and west of 106. The area in the middle of the image covers the entire Nipawin (Narrow Hills) provincial park. The look angle of the radar is 30 degrees and the size of the image is approximately 20 kilometers by 50 kilometers (12 by 30 miles). The image was produced by using only the L-band. The three polarization channels HH, HV and VV are illustrated by red, green and blue respectively. The changes in the intensity of each color are related to various surface conditions such as variations in forest stands, frozen or thawed condition of the surface, disturbances (fire and deforestation), and areas of regrowth. Most of the dark areas in the image are the ice-covered lakes in the region. The dark area on the top right corner of the image is the white Gull Lake north of the intersection of highway 120 and 913. The right middle part of the image shows Lake Ispuchaw and Lower Fishing Lake. The deforested areas are also shown by dark areas in the image. Since most of the logging practice at the Prince Albert area is around the major highways, the deforested areas can be easily detected as small geometrically shaped dark regions along the roads. At the time of the SIR-C/X-SAR overpass a major part of the forest is either frozen or undergoing the spring thaw. The L-band HH shows a high return in the jack pine forest. The reddish areas in the image are old jack pine forest, 12 to 17 meters (40to 55 feet) in height and 60 to 75 years old. The orange

  17. Integrating multisensor data and RADAR texture measures for land cover mapping (United States)

    Haack, Barry; Bechdol, Matthew


    This study evaluated multisensor spaceborne data from Landsat Thematic Mapper (TM) and Shuttle Imaging Radar (SIR-C) for East African landscapes including settlements, natural vegetation, and agriculture. An extensive landscape that has been difficult to accurately map with spaceborne remote sensing has been subtropical areas of savanna or woodland, especially when mixed with scattered agricultural practices. These varied vegetation communities are often very difficult to spectrally differentiate with optical data. This study examines the utility of radar to accurately locate areas of natural vegetation, scattered agricultural, and settlements. Radar data were able to accurately map these features with approximately the same accuracy as TM. In addition to comparing these two sensor types, four different geospatial manipulations of the radar data were examined. Those manipulations included measures of texture, the size of the texture window, data filtering prior to extraction of texture values, and post-classification smoothing. The variance (2nd order) measure of texture provided the best classification accuracies. The optimum window size for texture was a 13×13 pixel array and both pre- and post-classification filtering of the radar data significantly improved results.

  18. Space shuttle SRM field joint: Review paper

    Directory of Open Access Journals (Sweden)

    S. Mohammad Gharouni


    Full Text Available Due to Challenger space shuttle accident in 1986, significant research has been done concerning structural behavior of field joints in solid rocket boosters (SRB. The structural deformations between the clevis inner leg and the tang (male-to-female parts of joint, the sealing of the O-ring to prevent the hot gas in joints, has been neglected causing the failure of the vehicle. Redesigning the field joint in SRB engine by accurate analysis of dynamic and thermal loads and by design of insulator and good O-ring, the leakiness of combustion hot gases was eliminated. Some parts of field joint such as capture feature (CF and its third O-ring, J-leg insulator and shim were added to redesigned field joint. Also, some adjustments in sealing system and pins were done to promote the efficiency of the field joint. Due to different experimental analysis on assembled field joints with default imperfections, redesigned joints operated well. These redesigned field joints are commonly used in aerospace and mechanical structures. This paper investigates the original and the redesigned field joints with additional explanations of different parts of the redesigned joints.

  19. Radar Mosaic of Africa (United States)


    This is an image of equatorial Africa, centered on the equator at longitude 15degrees east. This image is a mosaic of almost 4,000 separate images obtained in 1996 by the L-band imaging radar onboard the Japanese Earth Resources Satellite. Using radar to penetrate the persistent clouds prevalent in tropical forests, the Japanese Earth Resources Satellite was able for the first time to image at high resolution this continental scale region during single flooding seasons. The area shown covers about 7.4 million square kilometers (2.8 million square miles) of land surface, spans more than 5,000 kilometers(3,100 miles) east and west and some 2,000 kilometers (1,240 miles) north and south. North is up in this image. At the full resolution of the mosaic (100 meters or 330 feet), this image is more than 500 megabytes in size, and was processed from imagery totaling more than 60 gigabytes.Central Africa was imaged twice in 1996, once between January and March, which is the major low-flood season in the Congo Basin, and once between October and November, which is the major high-flood season in the Congo Basin. The red color corresponds to the data from the low-flood season, the green to the high-flood season, and the blue to the 'texture' of the low-flood data. The forests appear green as a result, the flooded and palm forests, as well as urban areas, appear yellow, the ocean and lakes appear black, and savanna areas appear blue, black or green, depending on the savanna type, surface topography and other factors. The areas of the image that are black and white were mapped only between January and March 1996. In these areas, the black areas are savanna or open water, the gray are forests, and the white areas are flooded forests or urban areas. The Congo River dominates the middle of the image, where the nearby forests that are periodically flooded by the Congo and its tributaries stand out as yellow. The Nile River flows north from Lake Victoria in the middle right of the

  20. Radar rainfall image repair techniques

    Directory of Open Access Journals (Sweden)

    Stephen M. Wesson


    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

  1. Bistatic synthetic aperture radar (United States)

    Yates, Gillian

    Synthetic aperture radar (SAR) allows all-weather, day and night, surface surveillance and has the ability to detect, classify and geolocate objects at long stand-off ranges. Bistatic SAR, where the transmitter and the receiver are on separate platforms, is seen as a potential means of countering the vulnerability of conventional monostatic SAR to electronic countermeasures, particularly directional jamming, and avoiding physical attack of the imaging platform. As the receiving platform can be totally passive, it does not advertise its position by RF emissions. The transmitter is not susceptible to jamming and can, for example, operate at long stand-off ranges to reduce its vulnerability to physical attack. This thesis examines some of the complications involved in producing high-resolution bistatic SAR imagery. The effect of bistatic operation on resolution is examined from a theoretical viewpoint and analytical expressions for resolution are developed. These expressions are verified by simulation work using a simple 'point by point' processor. This work is extended to look at using modern practical processing engines for bistatic geometries. Adaptations of the polar format algorithm and range migration algorithm are considered. The principal achievement of this work is a fully airborne demonstration of bistatic SAR. The route taken in reaching this is given, along with some results. The bistatic SAR imagery is analysed and compared to the monostatic imagery collected at the same time. Demonstrating high-resolution bistatic SAR imagery using two airborne platforms represents what I believe to be a European first and is likely to be the first time that this has been achieved outside the US (the UK has very little insight into US work on this topic). Bistatic target characteristics are examined through the use of simulations. This also compares bistatic imagery with monostatic and gives further insight into the utility of bistatic SAR.

  2. Forward Looking Radar Imaging by Truncated Singular Value Decomposition and Its Application for Adverse Weather Aircraft Landing. (United States)

    Huang, Yulin; Zha, Yuebo; Wang, Yue; Yang, Jianyu


    The forward looking radar imaging task is a practical and challenging problem for adverse weather aircraft landing industry. Deconvolution method can realize the forward looking imaging but it often leads to the noise amplification in the radar image. In this paper, a forward looking radar imaging based on deconvolution method is presented for adverse weather aircraft landing. We first present the theoretical background of forward looking radar imaging task and its application for aircraft landing. Then, we convert the forward looking radar imaging task into a corresponding deconvolution problem, which is solved in the framework of algebraic theory using truncated singular decomposition method. The key issue regarding the selecting of the truncated parameter is addressed using generalized cross validation approach. Simulation and experimental results demonstrate that the proposed method is effective in achieving angular resolution enhancement with suppressing the noise amplification in forward looking radar imaging.

  3. Microbiology of the Space Shuttle water system. (United States)

    Koenig, D W; Pierson, D L


    The Space Shuttle has a once-through water system that is initially filled on the ground, partially drained before launch and then refilled with fuel-cell generated water on orbit. The microbiological standard for the Space Shuttle potable water system during this study period allowed only 1 microbe of any kind per l00mL and no detectable coliforms. Contamination episodes in more than 15 years of Shuttle operation have been rare; however, for the past 24 missions, bacterial contamination has been detected in 33% of the samples collected 3d before launch. These samples have had on average 55CFU/100mL of bacteria, with the median less than 1CFU/100mL. Burkholderia cepacia has been the primary contaminant of the Shuttle water supply system both before and after flight. Water samples assessed during the STS-70 mission aboard the Space Shuttle Discovery were found to be contaminated (Space Shuttle Columbia and the waste lines were found to harbor biofilms containing Bacillus spp. Nevertheless, the water systems of the four Space Shuttle vehicles provide extremely pure water.

  4. Using raindrop size distributions from different types of disdrometer to establish weather radar algorithms (United States)

    Baldini, Luca; Adirosi, Elisa; Roberto, Nicoletta; Vulpiani, Gianfranco; Russo, Fabio; Napolitano, Francesco


    Radar precipitation retrieval uses several relationships that parameterize precipitation properties (like rainfall rate and liquid water content and attenuation (in case of radars at attenuated frequencies such as those at C- and X- band) as a function of combinations of radar measurements. The uncertainty in such relations highly affects the uncertainty precipitation and attenuation estimates. A commonly used method to derive such relationships is to apply regression methods to precipitation measurements and radar observables simulated from datasets of drop size distributions (DSD) using microphysical and electromagnetic assumptions. DSD datasets are determined both by theoretical considerations (i.e. based on the assumption that the radar always samples raindrops whose sizes follow a gamma distribution) or from experimental measurements collected throughout the years by disdrometers. In principle, using long-term disdrometer measurements provide parameterizations more representative of a specific climatology. However, instrumental errors, specific of a disdrometer, can affect the results. In this study, different weather radar algorithms resulting from DSDs collected by diverse types of disdrometers, namely 2D video disdrometer, first and second generation of OTT Parsivel laser disdrometer, and Thies Clima laser disdrometer, in the area of Rome (Italy) are presented and discussed to establish at what extent dual-polarization radar algorithms derived from experimental DSD datasets are influenced by the different error structure of the different type of disdrometers used to collect the data.

  5. NAMMA TOGA RADAR DATA V1 (United States)

    National Aeronautics and Space Administration — The NAMMA TOGA Radar Data dataset consists of a collection of products derived from the NASA TOGA radar observations that were collected in the Republic of Cape...

  6. Extended Target Recognition in Cognitive Radar Networks

    Directory of Open Access Journals (Sweden)

    Xiqin Wang


    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.

  7. Weather radar rainfall data in urban hydrology

    DEFF Research Database (Denmark)

    Thorndahl, Søren; Einfalt, Thomas; Willems, Patrick


    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...

  8. ASTEROID RADAR V18.0 (United States)

    National Aeronautics and Space Administration — This data set is intended to include all published groundbased asteroid radar detections. The file is based on the collection of asteroid radar detections...

  9. ASTEROID RADAR V1.0 (United States)

    National Aeronautics and Space Administration — This dataset is intended to include all asteroid radar detections. An entry for each detection reports radar cross-section and circular polarization, if known, as...

  10. ASTEROID RADAR V17.0 (United States)

    National Aeronautics and Space Administration — This data set is intended to include all published groundbased asteroid radar detections. The file is based on the collection of asteroid radar detections...

  11. ASTEROID RADAR V15.0 (United States)

    National Aeronautics and Space Administration — This data set is intended to include all published groundbased asteroid radar detections. The file is based on the collection of asteroid radar detections...

  12. ASTEROID RADAR V16.0 (United States)

    National Aeronautics and Space Administration — This data set is intended to include all published groundbased asteroid radar detections. The file is based on the collection of asteroid radar detections...

  13. NOAA NEXt-Generation RADar (NEXRAD) Products (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,...

  14. Meteor detection on ST (MST) radars

    International Nuclear Information System (INIS)

    Avery, S.K.


    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

  15. Design of multi-frequency CW radars

    CERN Document Server

    Jankiraman, Mohinder


    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.

  16. Synthetic range profiling, ISAR imaging of sea vessels and feature extraction, using a multimode radar to classify targets: initial results from field trials

    CSIR Research Space (South Africa)

    Abdul Gaffar, MY


    Full Text Available -based classification of small to medium sized sea vessels in littoral condition. The experimental multimode radar is based on an experimental tracking radar that was modified to generate SRP and ISAR images in both search and tracking modes. The architecture...

  17. Airborne Differential Doppler Weather Radar (United States)

    Meneghini, R.; Bidwell, S.; Liao, L.; Rincon, R.; Heymsfield, G.; Hildebrand, Peter H. (Technical Monitor)


    The Precipitation Radar aboard the Tropical Rain Measuring Mission (TRMM) Satellite has shown the potential for spaceborne sensing of snow and rain by means of an incoherent pulsed radar operating at 13.8 GHz. The primary advantage of radar relative to passive instruments arises from the fact that the radar can image the 3-dimensional structure of storms. As a consequence, the radar data can be used to determine the vertical rain structure, rain type (convective/stratiform) effective storm height, and location of the melting layer. The radar, moreover, can be used to detect snow and improve the estimation of rain rate over land. To move toward spaceborne weather radars that can be deployed routinely as part of an instrument set consisting of passive and active sensors will require the development of less expensive, lighter-weight radars that consume less power. At the same time, the addition of a second frequency and an upgrade to Doppler capability are features that are needed to retrieve information on the characteristics of the drop size distribution, vertical air motion and storm dynamics. One approach to the problem is to use a single broad-band transmitter-receiver and antenna where two narrow-band frequencies are spaced apart by 5% to 10% of the center frequency. Use of Ka-band frequencies (26.5 GHz - 40 GHz) affords two advantages: adequate spatial resolution can be attained with a relatively small antenna and the differential reflectivity and mean Doppler signals are directly related to the median mass diameter of the snow and raindrop size distributions. The differential mean Doppler signal has the additional property that this quantity depends only on that part of the radial speed of the hydrometeors that is drop-size dependent. In principle, the mean and differential mean Doppler from a near-nadir viewing radar can be used to retrieve vertical air motion as well as the total mean radial velocity. In the paper, we present theoretical calculations for the

  18. Radar Observation of Insects - Mosquitoes (United States)

    Frost, E.; Downing, J.


    Tests were conducted at several sites over the coastal lowlands of New Jersey and over a region of high plains and low mountains in Oklahoma. In one area, a salt marsh in New Jersey, extensive ground tests were combined with laboratory data on expected insect backscatter to arrive at an extremely convincing model of the insect origin of most Dot Angels. A great deal of insight was studied from radar on the buildup and dispersal of insect swarms, since radar can follow where other means of trapping and observation cannot. Data on large-scale behavior as a function of wind and topography are presented. Displayed techniques which show individual or small swarm motion within some larger cloud or mass, or which can show the overall motion over great distances were developed. The influence of wind and terrain on insect motion and dispersal is determined from radar data.

  19. Microwave emissions from police radar. (United States)

    Fink, J M; Wagner, J P; Congleton, J J; Rock, J C


    This study evaluated police officers' exposures to microwaves emitted by traffic radar units. Exposure measurements were taken at approximated ocular and testicular levels of officers seated in patrol vehicles. Comparisons were made of the radar manufacturers' published maximum power density specifications and actual measured power densities taken at the antenna faces of those units. Four speed-enforcement agencies and one transportation research institute provided 54 radar units for evaluation; 17 different models, encompassing 4 frequency bands and 3 antenna configurations, were included. Four of the 986 measurements taken exceeded the 5 mW/cm2 limit accepted by the International Radiation Protection Association and the National Council on Radiation Protection and Measurement, though none exceeded the American Conference of Governmental Industrial Hygienists, American National Standards Institute, Institute of Electrical and Electronic Engineers, or Occupational Safety and Health Administration standard of 10 mW/cm2. The four high measurements were maximum power density readings taken directly in front of the radar. Of the 812 measurements taken at the officers' seated ocular and testicular positions, none exceeded 0.04 mW/cm2; the highest of these (0.034 mW/cm2) was less than 1% of the most conservative current safety standards. High exposures in the limited region directly in front of the radar aperture are easily avoided with proper training. Results of this study indicate that police officer exposure to microwave radiation is apparently minimal. However, because of uncertainty in the medical and scientific communities concerning nonionizing radiation, it is recommended that law enforcement agencies implement a policy of prudent avoidance, including purchasing units with the lowest published maximum power densities, purchasing dash/rear deck-mounted units with antennae mounted outside the patrol vehicle, and training police officers to use the "stand-by" mode

  20. Radar mutual information and communication channel capacity of integrated radar-communication system using MIMO

    Directory of Open Access Journals (Sweden)

    Renhui Xu


    Full Text Available Integrated radar-communication system based on multiple input and multiple output (MIMO shares the hardware resource and spectrum to fulfill radar and communication functions, simultaneously. The baseband signal models of the MIMO radar and the integrated radar-communication system are set up. Then, the radar mutual information and the communication channel capacity are derived accordingly. Radar mutual information is used to evaluate the radar performance; communication channel capacity is one of the methods used to measure the communication capability. The influences of signal-to-noise ratio and the number of antennas, on the mutual information and channel capacity are presented through simulations.

  1. Radar research at The Pennsylvania State University Radar and Communications Laboratory (United States)

    Narayanan, Ram M.


    The Radar and Communications Laboratory (RCL) at The Pennsylvania State University is at the forefront of radar technology and is engaged in cutting edge research in all aspects of radar, including modeling and simulation studies of novel radar paradigms, design and development of new types of radar architectures, and extensive field measurements in realistic scenarios. This paper summarizes the research at The Pennsylvania State University's Radar and Communications Laboratory and relevant collaborative research with several groups over the past 15 years in the field of radar and related technologies, including communications, radio frequency identification (RFID), and spectrum sensing.

  2. Goldstone solar system radar signal processing (United States)

    Jurgens, R. F.; Satorius, E.; Sanchez, O.


    A performance analysis of the planetary radar data acquisition system is presented. These results extend previous computer simulation analysis and are facilitated by the development of a simple analytical model that predicts radar system performance over a wide range of operational parameters. The results of this study are useful to both the radar systems designer and the science investigator in establishing operational radar data acquisition parameters which result in the best systems performance for a given set of input conditions.

  3. Fmcw Mmw Radar For Automotive Longitudinal Control


    David, William


    This report presents information on millimeter wave (MMW) radar for automotive longitudinal control. It addresses the fundamental capabilities and limitations of millimeter waves for ranging and contrasts their operation with that of conventional microwave radar. The report analyzes pulsed and FMCW radar configurations, and provides detailed treatment of FMCW radar operating at MMW frequency, its advantages and disadvantages as they relate to range and velocity measurements.

  4. Radar operation in a hostile electromagnetic environment

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter


    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.

  5. Wind Turbine Radar Cross Section

    Directory of Open Access Journals (Sweden)

    David Jenn


    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.

  6. Compressive sensing for urban radar

    CERN Document Server

    Amin, Moeness


    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

  7. Simulation model study of limitation on the locating distance of a ground penetrating radar; Chichu tansa radar no tansa kyori genkai ni kansuru simulation model no kochiku

    Energy Technology Data Exchange (ETDEWEB)

    Nakauchi, T.; Tsunasaki, M.; Kishi, M.; Hayakawa, H. [Osaka Gas Co. Ltd., Osaka (Japan)


    Various simulations were carried out under various laying conditions to obtain the limitation of locating distance for ground penetrating radar. Recently, ground penetrating radar has been remarked as location technology of obstacles such as the existing buried objects. To enhance the theoretical model (radar equation) of a maximum locating distance, the following factors were examined experimentally using pulse ground penetrating radar: ground surface conditions such as asphalt pavement, diameter of buried pipes, material of buried pipes, effect of soil, antenna gain. The experiment results well agreed with actual field experiment ones. By adopting the antenna gain and effect of the ground surface, the more practical simulation using underground models became possible. The maximum locating distance was more improved by large antenna than small one in actual field. It is assumed that large antenna components contributed to improvement of gain and reduction of attenuation during passing through soil. 5 refs., 12 figs.

  8. Tracking radar studies of bird migration (United States)

    Williams, T. C.; Williams, J. M.; Teal, J. M.; Kanwisher, J. W.


    The application of tracking radar for determining the flight paths of migratory birds is discussed. The effects produced by various meteorological parameters are described. Samples of radar scope presentations obtained during tracking studies are presented. The characteristics of the radars and their limitations are examined.

  9. Comparison of radar data versus rainfall data. (United States)

    Espinosa, B; Hromadka, T V; Perez, R


    Doppler radar data are increasingly used in rainfall-runoff synthesis studies, perhaps due to radar data availability, among other factors. However, the veracity of the radar data are often a topic of concern. In this paper, three Doppler radar outcomes developed by the United States National Weather Service at three radar sites are examined and compared to actual rain gage data for two separate severe storm events in order to assess accuracy in the published radar estimates of rainfall. Because the subject storms were very intense rainfall events lasting approximately one hour in duration, direct comparisons between the three radar gages themselves can be made, as well as a comparison to rain gage data at a rain gage location subjected to the same storm cells. It is shown that topographic interference with the radar outcomes can be a significant factor leading to differences between radar and rain gage readings, and that care is needed in calibrating radar outcomes using available rain gage data in order to interpolate rainfall estimates between rain gages using the spatial variation observed in the radar readings. The paper establishes and describes•the need for "ground-truthing" of radar data, and•possible errors due to topographic interference.

  10. Comparison of mimo radar concepts: Detection performance

    NARCIS (Netherlands)

    Rossum, W.L. van; Huizing, A.G.


    In this paper, four different array radar concepts are compared: pencil beam, floodlight, monostatic MIMO, and multistatic MIMO. The array radar concepts show an increase in complexity accompanied by an increase in diversity. The comparison between the radar concepts is made by investigating the

  11. Efficient Ways to Learn Weather Radar Polarimetry (United States)

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


    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. Principles of modern radar advanced techniques

    CERN Document Server

    Melvin, William


    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.

  13. Realization of a scalable airborne radar

    NARCIS (Netherlands)

    Otten, M.P.G.; Vermeulen, B.C.B.; Liempt, L.J. van; Halsema, D. van; Jongh, R.V. de; Es, J. van


    Modern airborne ground surveillance radar systems are increasingly based on Active Electronically Scanned Array (AESA) antennas. Efficient use of array technology and the need for radar solutions for various airborne platforms, manned and unmanned, leads to the design of scalable radar systems. The

  14. Nucleocytoplasmic Shuttling of Influenza A Virus Proteins

    Directory of Open Access Journals (Sweden)

    Jing Li


    Full Text Available Influenza viruses transcribe and replicate their genomes in the nuclei of infected host cells. The viral ribonucleoprotein (vRNP complex of influenza virus is the essential genetic unit of the virus. The viral proteins play important roles in multiple processes, including virus structural maintenance, mediating nucleocytoplasmic shuttling of the vRNP complex, virus particle assembly, and budding. Nucleocytoplasmic shuttling of viral proteins occurs throughout the entire virus life cycle. This review mainly focuses on matrix protein (M1, nucleoprotein (NP, nonstructural protein (NS1, and nuclear export protein (NEP, summarizing the mechanisms of their nucleocytoplasmic shuttling and the regulation of virus replication through their phosphorylation to further understand the regulation of nucleocytoplasmic shuttling in host adaptation of the viruses.

  15. The space shuttle program technologies and accomplishments

    CERN Document Server

    Sivolella, Davide


    This book tells the story of the Space Shuttle in its many different roles as orbital launch platform, orbital workshop, and science and technology laboratory. It focuses on the technology designed and developed to support the missions of the Space Shuttle program. Each mission is examined, from both the technical and managerial viewpoints. Although outwardly identical, the capabilities of the orbiters in the late years of the program were quite different from those in 1981. Sivolella traces the various improvements and modifications made to the shuttle over the years as part of each mission story. Technically accurate but with a pleasing narrative style and simple explanations of complex engineering concepts, the book provides details of many lesser known concepts, some developed but never flown, and commemorates the ingenuity of NASA and its partners in making each Space Shuttle mission push the boundaries of what we can accomplish in space. Using press kits, original papers, newspaper and magazine articles...

  16. Random Vibration of Space Shuttle Weather Protection Systems

    Directory of Open Access Journals (Sweden)

    Isaac Elishakoff


    Full Text Available The article deals with random vibrations of the space shuttle weather protection systems. The excitation model represents a fit to the measured experimental data. The cross-spectral density is given as a convex combination of three exponential functions. It is shown that for the type of loading considered, the Bernoulli-Euler theory cannot be used as a simplified approach, and the structure will be more properly modeled as a Timoshenko beam. Use of the simple Bernoulli-Euler theory may result in an error of about 50% in determining the mean-square value of the bending moment in the weather protection system.

  17. CERN Shuttles - Enlarged Regular Shuttle Services as from 8/02/2010

    CERN Multimedia


    As of Monday 8 February 2010, please note the enhancement of the regular shuttle services: - with now two shuttles dedicated to the transportation within and between both CERN sites, Meyrin and Prevessin with bus stop at more buildings - To and from the Geneva airport every hour (from building 500) to complement the TPG bus Y For timetable details, please click here: GS-SEM

  18. NASA Shuttle Radar Topography Mission Global 3 arc second sub-sampled V003 (United States)

    National Aeronautics and Space Administration — The NASA SRTM data sets result from a collaborative effort by the National Aeronautics and Space Administration (NASA) and the National Geospatial-Intelligence...

  19. NASA Shuttle Radar Topography Mission Combined Image Data Set V003 (United States)

    National Aeronautics and Space Administration — The NASA SRTM data sets result from a collaborative effort by the National Aeronautics and Space Administration (NASA) and the National Geospatial-Intelligence...

  20. NASA Shuttle Radar Topography Mission Global 3 arc second V003 (United States)

    National Aeronautics and Space Administration — The NASA SRTM data sets result from a collaborative effort by the National Aeronautics and Space Administration (NASA) and the National Geospatial-Intelligence...

  1. NASA Shuttle Radar Topography Mission Water Body Data Shapefiles & Raster Files V003 (United States)

    National Aeronautics and Space Administration — The NASA SRTM data sets result from a collaborative effort by the National Aeronautics and Space Administration (NASA) and the National Geospatial-Intelligence...

  2. NASA Shuttle Radar Topography Mission Global 30 arc second V002 (United States)

    National Aeronautics and Space Administration — The NASA SRTM data sets result from a collaborative effort by the National Aeronautics and Space Administration (NASA) and the National Geospatial-Intelligence...

  3. NASA Shuttle Radar Topography Mission Global 1 arc second number V003 (United States)

    National Aeronautics and Space Administration — The NASA SRTM data sets result from a collaborative effort by the National Aeronautics and Space Administration (NASA) and the National Geospatial-Intelligence...

  4. NASA Shuttle Radar Topography Mission Global 3 arc second number V003 (United States)

    National Aeronautics and Space Administration — The NASA SRTM data sets result from a collaborative effort by the National Aeronautics and Space Administration (NASA) and the National Geospatial-Intelligence...

  5. NASA Shuttle Radar Topography Mission Global 1 arc second V003 (United States)

    National Aeronautics and Space Administration — The NASA SRTM data sets result from a collaborative effort by the National Aeronautics and Space Administration (NASA) and the National Geospatial-Intelligence...

  6. Improved Detection of Human Respiration Using Data Fusion Basedon a Multistatic UWB Radar

    Directory of Open Access Journals (Sweden)

    Hao Lv


    Full Text Available This paper investigated the feasibility for improved detection of human respiration using data fusion based on a multistatic ultra-wideband (UWB radar. UWB-radar-based respiration detection is an emerging technology that has great promise in practice. It can be applied to remotely sense the presence of a human target for through-wall surveillance, post-earthquake search and rescue, etc. In these applications, a human target’s position and posture are not known a priori. Uncertainty of the two factors results in a body orientation issue of UWB radar, namely the human target’s thorax is not always facing the radar. Thus, the radial component of the thorax motion due to respiration decreases and the respiratory motion response contained in UWB radar echoes is too weak to be detected. To cope with the issue, this paper used multisensory information provided by the multistatic UWB radar, which took the form of impulse radios and comprised one transmitting and four separated receiving antennas. An adaptive Kalman filtering algorithm was then designed to fuse the UWB echo data from all the receiving channels to detect the respiratory-motion response contained in those data. In the experiment, a volunteer’s respiration was correctly detected when he curled upon a camp bed behind a brick wall. Under the same scenario, the volunteer’s respiration was detected based on the radar’s single transmitting-receiving channels without data fusion using conventional algorithm, such as adaptive line enhancer and single-channel Kalman filtering. Moreover, performance of the data fusion algorithm was experimentally investigated with different channel combinations and antenna deployments. The experimental results show that the body orientation issue for human respiration detection via UWB radar can be dealt well with the multistatic UWB radar and the Kalman-filter-based data fusion, which can be applied to improve performance of UWB radar in real applications.

  7. Space Radar Image of the Yucatan Impact Crater Site (United States)


    This is a radar image of the southwest portion of the buried Chicxulub impact crater in the Yucatan Peninsula, Mexico. The radar image was acquired on orbit 81 of space shuttle Endeavour on April 14, 1994 by the Spaceborne Imaging Radar C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR). The image is centered at 20 degrees north latitude and 90 degrees west longitude. Scientists believe the crater was formed by an asteroid or comet which slammed into the Earth more than 65 million years ago. It is this impact crater that has been linked to a major biological catastrophe where more than 50 percent of the Earth's species, including the dinosaurs, became extinct. The 180-to 300-kilometer-diameter (110- to 180-mile)crater is buried by 300 to 1,000 meters (1,000 to 3,000 feet) of limestone. The exact size of the crater is currently being debated by scientists. This is a total power radar image with L-band in red, C-band in green, and the difference between C-band L-band in blue. The 10-kilometer-wide (6-mile) band of yellow and pink with blue patches along the top left (northwestern side) of the image is a mangrove swamp. The blue patches are islands of tropical forests created by freshwater springs that emerge through fractures in the limestone bedrock and are most abundant in the vicinity of the buried crater rim. The fracture patterns and wetland hydrology in this region are controlled by the structure of the buried crater. Scientists are using the SIR-C/X-SAR imagery to study wetland ecology and help determine the exact size of the impact crater. 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 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

  8. Kinetic simulation of malate-aspartate and citrate-pyruvate shuttles in association with Krebs cycle. (United States)

    Korla, Kalyani; Vadlakonda, Lakshmipathi; Mitra, Chanchal K


    In the present work, we have kinetically simulated two mitochondrial shuttles, malate-aspartate shuttle (used for transferring reducing equivalents) and citrate-pyruvate shuttle (used for transferring carbon skeletons). However, the functions of these shuttles are not limited to the points mentioned above, and they can be used in different arrangements to meet different cellular requirements. Both the shuttles are intricately associated with Krebs cycle through the metabolites involved. The study of this system of shuttles and Krebs cycle explores the response of the system in different metabolic environments. Here, we have simulated these subsets individually and then combined them to study the interactions among them and to bring out the dynamics of these pathways in focus. Four antiports and a pyruvate pump were modelled along with the metabolic reactions on both sides of the inner mitochondrial membrane. Michaelis-Menten approach was extended for deriving rate equations of every component of the system. Kinetic simulation was carried out using ordinary differential equation solver in GNU Octave. It was observed that all the components attained steady state, sooner or later, depending on the system conditions. Progress curves and phase plots were plotted to understand the steady state behaviour of the metabolites involved. A comparative analysis between experimental and simulated data show fair agreement thus validating the usefulness and applicability of the model.

  9. FMWC Radar for Breath Detection

    DEFF Research Database (Denmark)

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

    breathing through walls. Other remote breath tracking systems has been presented that are based on the Ultra-wideband radar technique. However, these systems have two drawbacks. Firstly, they penetrate walls. It is therefore harder to contain the emitted radiation and they could be used for unsolicited...

  10. Fractal radar scattering from soil (United States)

    Oleschko, Klaudia; Korvin, Gabor; Figueroa, Benjamin; Vuelvas, Marco Antonio; Balankin, Alexander S.; Flores, Lourdes; Carreón, Dora


    A general technique is developed to retrieve the fractal dimension of self-similar soils through microwave (radar) scattering. The technique is based on a mathematical model relating the fractal dimensions of the georadargram to that of the scattering structure. Clear and different fractal signatures have been observed over four geosystems (soils and sediments) compared in this work.

  11. Future of synthetic aperture radar (United States)

    Barath, F. T.


    The present status of the applications of Synthetic Aperture Radars (SARs) is reviewed, and the technology state-of-the art as represented by the Seasat-A and SIR-A SARs examined. The potential of SAR applications, and the near- and longer-term technology trends are assessed.

  12. UWB radar multipath propagation effects

    Czech Academy of Sciences Publication Activity Database

    Čermák, D.; Schejbal, V.; NĚMEC, Z.; Bezoušek, P.; Fišer, Ondřej


    Roč. 11, - (2005), --- ISSN 1211-6610 R&D Projects: GA MPO FT-TA2/030 Institutional research plan: CEZ:AV0Z30420517 Keywords : UWB radar * multipath propagation Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  13. MÉTODOS DE PROSPECCIÓN GEOFÍSICA EN ARQUEOLOGÍA. EXPERIMENTACIÓN CON RADAR DE PENETRACIÓN TERRESTRE (GPR EN CONCHEROS ARTIFICIALES (Geophysical methods in archaeology. Experimentation with ground penetrating radar (GPR in artificial shell mounds

    Directory of Open Access Journals (Sweden)

    Fernando Santiago


    Full Text Available La prospección con georadar en sitios arqueológicos de la costa atlántica de Tierra del Fuego presenta dificultades, en cuanto a la calidad de los registros y su funcionalidad en relación a la detección de objetos arqueológicos presentes en el subsuelo. Para dilucidar las causas, se diseñó un experimento en laboratorio reproduciendo el entorno natural y cultural. Se replicó un conchero en una caja de frente transparente, incorporando materiales óseos y líticos y usando sedimento estéril del sitio La Arcillosa 2. Se efectuó un análisis granulométrico y separación magnética del sedimento estéril, y se sondeó con una antena de 1,5 GHz. El conchero, incluido en un depósito de arena con contenido de humedad entre 2,1 y 4,5%, fue visible en los registros. Los restos óseos generaron anomalías nítidas, debido al contraste de sus propiedades dieléctricas con las arenas portadoras. Con humedad mayor a 8,5% o con cobertura de suelos y gramíneas, los registros resultaron difusos. Los minerales paramagnéticos, ferromagnéticos (24,5% y altamente magnéticos (3,6% del depósito provocaron atenuación de las ondas electromagnéticas. Los resultados de la aplicación de esta técnica para los concheros del norte de Tierra del Fuego, en relación al tiempo de trabajo en campo y en laboratorio, resultan pocos satisfactorios. ENGLISH: Archaeological sites on the northern Atlantic coast of Tierra del Fuego show a poor response to geophysical exploration, using ground penetrating radar. In order to elucidate its causes, a laboratory experiment was designed, creating the natural environmental conditions. Materials and sterile sediment from the site of La Arcillosa 2 (Chico River Basin, northeast of Tierra del Fuego were utilized to replicate an artificial shell midden in a transparent box. Particle size analysis and magnetic separation of the sterile soil were performed, and various surveys were conducted with a 1.5 GHz antenna. The shell

  14. Research relative to weather radar measurement techniques (United States)

    Smith, Paul L.


    Research relative to weather radar measurement techniques, which involves some investigations related to measurement techniques applicable to meteorological radar systems in Thailand, is reported. A major part of the activity was devoted to instruction and discussion with Thai radar engineers, technicians, and meteorologists concerning the basic principles of radar meteorology and applications to specific problems, including measurement of rainfall and detection of wind shear/microburst hazards. Weather radar calibration techniques were also considered during this project. Most of the activity took place during two visits to Thailand, in December 1990 and February 1992.

  15. The MU radar now partly in operation (United States)

    Kato, S.; Ogawa, T.; Tsuda, T.; Sato, T.; Kimura, I.; Fukao, S.


    The MU radar (middle- and upper-atmosphere radar) of RASC (Radio Atmospheric Science Center, Kyoto University) is now partly in operation, although the facility will be completed in 1985. The active array system of the radar makes it possible to steer the radar beam as fast as in each interpulse period. Various sophisticated experiments are expected to be performed by the system. A preliminary observation was successful to elucidate atmospheric motions during Typhoon No. 5 which approached the radar site in August, 1983.

  16. Analysis of Radar Doppler Signature from Human Data

    Directory of Open Access Journals (Sweden)



    Full Text Available This paper presents the results of time (autocorrelation and time-frequency (spectrogram analyses of radar signals returned from the moving human targets. When a radar signal falls on the human target which is moving toward or away from the radar, the signals reflected from different parts of his body produce a Doppler shift that is proportional to the velocity of those parts. Moving parts of the body causes the characteristic Doppler signature. The main contribution comes from the torso which causes the central Doppler frequency of target. The motion of arms and legs induces modulation on the returned radar signal and generates sidebands around the central Doppler frequency, referred to as micro-Doppler signatures. Through analyses on experimental data it was demonstrated that the human motion signature extraction is better using spectrogram. While the central Doppler frequency can be determined using the autocorrelation and the spectrogram, the extraction of the fundamental cadence frequency using the autocorrelation is unreliable when the target is in the clutter presence. It was shown that the fundamental cadence frequency increases with increasing dynamic movement of people and simultaneously the possibility of its extraction is proportional to the degree of synchronization movements of persons in the group.

  17. Radar signal transmission and switching over optical networks (United States)

    Esmail, Maged A.; Ragheb, Amr; Seleem, Hussein; Fathallah, Habib; Alshebeili, Saleh


    In this paper, we experimentally demonstrate a radar signal distribution over optical networks. The use of fiber enables us to distribute radar signals to distant sites with a low power loss. Moreover, fiber networks can reduce the radar system cost, by sharing precise and expensive radar signal generation and processing equipment. In order to overcome the bandwidth challenges in electrical switches, a semiconductor optical amplifier (SOA) is used as an all-optical device for wavelength conversion to the desired port (or channel) of a wavelength division multiplexing (WDM) network. Moreover, the effect of chromatic dispersion in double sideband (DSB) signals is combated by generating optical single sideband (OSSB) signals. The optimal values of the SOA device parameters required to generate an OSSB with a high sideband suppression ratio (SSR) are determined. We considered various parameters such as injection current, pump power, and probe power. In addition, the effect of signal wavelength conversion and transmission over fiber are studied in terms of signal dynamic range.

  18. Enhanced Weather Radar (EWxR) System (United States)

    Kronfeld, Kevin M. (Technical Monitor)


    An airborne weather radar system, the Enhanced Weather Radar (EWxR), with enhanced on-board weather radar data processing was developed and tested. The system features additional weather data that is uplinked from ground-based sources, specialized data processing, and limited automatic radar control to search for hazardous weather. National Weather Service (NWS) ground-based Next Generation Radar (NEXRAD) information is used by the EWxR system to augment the on-board weather radar information. The system will simultaneously display NEXRAD and on-board weather radar information in a split-view format. The on-board weather radar includes an automated or hands-free storm-finding feature that optimizes the radar returns by automatically adjusting the tilt and range settings for the current altitude above the terrain and searches for storm cells near the atmospheric 0-degree isotherm. A rule-based decision aid was developed to automatically characterize cells as hazardous, possibly-hazardous, or non-hazardous based upon attributes of that cell. Cell attributes are determined based on data from the on-board radar and from ground-based radars. A flight path impact prediction algorithm was developed to help pilots to avoid hazardous weather along their flight plan and their mission. During development the system was tested on the NASA B757 aircraft and final tests were conducted on the Rockwell Collins Sabreliner.

  19. Status and Prospects of Radar Polarimetry Techniques

    Directory of Open Access Journals (Sweden)

    Wang Xuesong


    Full Text Available Radar polarimetry is an applied fundamental science field that is focused on understanding interaction processes between radar waves and targets and disclosing their mechanisms. Radar polarimetry has significant application prospects in the fields of microwave remote sensing, earth observation, meteorological measurement, battlefield reconnaissance, anti-interference, target recognition, and so on. This study briefly reviews the development history of radar polarization theory and technology. Next, the state of the art of several key technologies within radar polarimetry, including the precise acquisition of radar polarization information, polarization-sensitive array signal processing, target polarization characteristics, polarization antiinterference, and target polarization classification and recognition, is summarized. Finally, the future developments of radar polarization technology are considered.

  20. Radar research at the University of Kansas (United States)

    Blunt, Shannon D.; Allen, Christopher; Arnold, Emily; Hale, Richard; Hui, Rongqing; Keshmiri, Shahriar; Leuschen, Carlton; Li, Jilu; Paden, John; Rodriguez-Morales, Fernando; Salandrino, Alessandro; Stiles, James


    Radar research has been synonymous with the University of Kansas (KU) for over half a century. As part of this special session organized to highlight significant radar programs in academia, this paper surveys recent and ongoing work at KU. This work encompasses a wide breadth of sensing applications including the remote sensing of ice sheets, autonomous navigation methods for unmanned aerial vehicles (UAVs), novel laser radar capabilities, detection of highenergy cosmic rays using bistatic radar, different forms of waveform diversity such as MIMO radar and pulse agility, and various radar-embedded communication methods. The results of these efforts impact our understanding of the changing nature of the environment, address the proliferation of unmanned systems in the US airspace, realize new sensing modalities enabled by the joint consideration of electromagnetics and signal processing, and greater facilitate radar operation in an increasingly congested and contested spectrum.

  1. A Technique for Real-Time Ionospheric Ranging Error Correction Based On Radar Dual-Frequency Detection (United States)

    Lyu, Jiang-Tao; Zhou, Chen


    Ionospheric refraction is one of the principal error sources for limiting the accuracy of radar systems for space target detection. High-accuracy measurement of the ionospheric electron density along the propagation path of radar wave is the most important procedure for the ionospheric refraction correction. Traditionally, the ionospheric model and the ionospheric detection instruments, like ionosonde or GPS receivers, are employed for obtaining the electron density. However, both methods are not capable of satisfying the requirements of correction accuracy for the advanced space target radar system. In this study, we propose a novel technique for ionospheric refraction correction based on radar dual-frequency detection. Radar target range measurements at two adjacent frequencies are utilized for calculating the electron density integral exactly along the propagation path of the radar wave, which can generate accurate ionospheric range correction. The implementation of radar dual-frequency detection is validated by a P band radar located in midlatitude China. The experimental results present that the accuracy of this novel technique is more accurate than the traditional ionospheric model correction. The technique proposed in this study is very promising for the high-accuracy radar detection and tracking of objects in geospace.

  2. Fpga based L-band pulse doppler radar design and implementation (United States)

    Savci, Kubilay

    point arithmetic operations as it is fast and facilitates source requirement as it consumes less hardware than floating point arithmetic operations. The software uses floating point arithmetic operations, which ensure precision in processing at the expense of speed. The functionality of the radar system has been tested for experimental validation in the field with a moving car and the validation of submodules are tested with synthetic data simulated on MATLAB.

  3. Application of an Elongated Kelvin Model to Space Shuttle Foams (United States)

    Sullivan, Roy M.; Ghosn, Louis J.; Lerch, Bradley A.


    The space shuttle foams are rigid closed-cell polyurethane foams. The two foams used most-extensively oil space shuttle external tank are BX-265 and NCFL4-124. Because of the foaming and rising process, the foam microstructures are elongated in the rise direction. As a result, these two foams exhibit a nonisotropic mechanical behavior. A detailed microstructural characterization of the two foams is presented. Key features of the foam cells are described and the average cell dimensions in the two foams are summarized. Experimental studies are also conducted to measure the room temperature mechanical response of the two foams in the two principal material directions (parallel to the rise and perpendicular to the rise). The measured elastic modulus, proportional limit stress, ultimate tensile strength, and Poisson's ratios are reported. The generalized elongated Kelvin foam model previously developed by the authors is reviewed and the equations which result from this model are summarized. Using the measured microstructural dimensions and the measured stiffness ratio, the foam tensile strength ratio and Poisson's ratios are predicted for both foams and are compared with the experimental data. The predicted tensile strength ratio is in close agreement with the measured strength ratio for both BX-265 and NCFI24-124. The comparison between the predicted Poisson's ratios and the measured values is not as favorable.

  4. Space Shuttle Solid Rocket Booster Debris Assessment (United States)

    Kendall, Kristin; Kanner, Howard; Yu, Weiping


    The Space Shuttle Columbia Accident revealed a fundamental problem of the Space Shuttle Program regarding debris. Prior to the tragedy, the Space Shuttle requirement stated that no debris should be liberated that would jeopardize the flight crew and/or mission success. When the accident investigation determined that a large piece of foam debris was the primary cause of the loss of the shuttle and crew, it became apparent that the risk and scope of - damage that could be caused by certain types of debris, especially - ice and foam, were not fully understood. There was no clear understanding of the materials that could become debris, the path the debris might take during flight, the structures the debris might impact or the damage the impact might cause. In addition to supporting the primary NASA and USA goal of returning the Space Shuttle to flight by understanding the SRB debris environment and capability to withstand that environment, the SRB debris assessment project was divided into four primary tasks that were required to be completed to support the RTF goal. These tasks were (1) debris environment definition, (2) impact testing, (3) model correlation and (4) hardware evaluation. Additionally, the project aligned with USA's corporate goals of safety, customer satisfaction, professional development and fiscal accountability.

  5. Intelligent Shuttle Management and Routing Algorithm (United States)

    Thomas, Toshen M.; Subashanthini, S.


    Nowadays, most of the big Universities and campuses have Shuttle cabs running in them to cater the transportational needs of the students and faculties. While some shuttle services ask for a meagre sum to be paid for the usage, no digital payment system is onboard these vehicles to go truly cashless. Even more troublesome is the fact that sometimes during the day, some of these cabs run with bare number of passengers, which can result in unwanted budget loss to the shuttle operator. The main purpose of this paper is to create a system with two types of applications: A web portal and an Android app, to digitize the Shuttle cab industry. This system can be used for digital cashless payment feature, tracking passengers, tracking cabs and more importantly, manage the number of shuttle cabs in every route to maximize profit. This project is built upon an ASP.NET website connected to a cloud service along with an Android app that tracks and reads the passengers ID using an attached barcode reader along with the current GPS coordinates, and sends these data to the cloud for processing using the phone’s internet connectivity.

  6. Tactile Radar: experimenting a computer game with visually disabled. (United States)

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


    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.

  7. Penn State Radar Systems: Implementation and Observations (United States)

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


    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.

  8. Space Radar Image of the Lost City of Ubar (United States)


    This is a radar image of the region around the site of the lost city of Ubar in southern Oman, on the Arabian Peninsula. The ancient city was discovered in 1992 with the aid of remote sensing data. Archeologists believe Ubar existed from about 2800 B.C. to about 300 A.D. and was a remote desert outpost where caravans were assembled for the transport of frankincense across the desert. This image was acquired on orbit 65 of space shuttle Endeavour on April 13, 1994 by the Spaceborne Imaging Radar C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR). The SIR-C image shown is centered at 18.4 degrees north latitude and 53.6 degrees east longitude. The image covers an area about 50 by 100 kilometers (31 miles by 62 miles). The image is constructed from three of the available SIR-C channels and displays L-band, HH (horizontal transmit and receive) data as red, C-band HH as blue, and L-band HV (horizontal transmit, vertical receive) as green. The prominent magenta colored area is a region of large sand dunes, which are bright reflectors at both L-and C-band. The prominent green areas (L-HV) are rough limestone rocks, which form a rocky desert floor. A major wadi, or dry stream bed, runs across the middle of the image and is shown largely in white due to strong radar scattering in all channels displayed (L and C HH, L-HV). The actual site of the fortress of the lost city of Ubar, currently under excavation, is near the Wadi close to the center of the image. The fortress is too small to be detected in this image. However, tracks leading to the site, and surrounding tracks, appear as prominent, but diffuse, reddish streaks. These tracks have been used in modern times, but field investigations show many of these tracks were in use in ancient times as well. Mapping of these tracks on regional remote sensing images was a key to recognizing the site as Ubar in 1992. This image, and ongoing field investigations, will help shed light on a little known early civilization. Spaceborne

  9. Dynamic displacement monitoring of long-span bridges with a microwave radar interferometer (United States)

    Zhang, Bochen; Ding, Xiaoli; Werner, Charles; Tan, Kai; Zhang, Bin; Jiang, Mi; Zhao, Jingwen; Xu, Youlin


    Structural health monitoring of long-span bridges is a critical process in ensuring the operational safety of the structures. In this paper, we present experimental results of monitoring the displacements of two long-span bridges in Hong Kong Ting Kau Bridge (TKB) and Tsing Ma Bridge (TMB) with a terrestrial microwave radar interferometer named the GAMMA Portable Radar Interferometer (GPRI). A technique for fusing the measurements from two receiving antennas of the radar instrument is proposed. In addition, a two-step phase unwrapping approach is also tested. The results reveal the bridge dynamic responses under different loading conditions, including winds, vehicle traffic, and passing trains. The results also show that the terrestrial microwave radar interferometer can be used to monitor the dynamics of long-span bridges with unprecedented spatial and temporal resolutions.

  10. Multistatic Wireless Fidelity Network Based Radar – Results of the Chrcynno Experiment

    Directory of Open Access Journals (Sweden)

    S. Rzewuski


    Full Text Available This paper presents the theory and experimental result of passive radar using WIFI transmitters as illuminators of opportunity. As a result of experiments conducted on 17th August 2013 at airfield Chrcynno a Cessna C208 airplane was detected and tracked using multistatic passive radar system based on low power signal from WIFI network nodes, which were acting as non cooperative illuminators of opportunity. In the experiment 3 wireless access points were communicating with each other and illuminating the radar scene (airfield. The direct reference and reflected (surveillance signals have been acquired and processed using specially developed algorithm presented in the paper. After signal processing using Passive Coherent Location methods target has been detected. This paper describes in details the algorithms and the results of the experiment for the multistatic passive radar based on the WIFI signal.

  11. Detecting and classifying low probability of intercept radar

    CERN Document Server

    Pace, Philip E


    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.

  12. Radar based autonomous sensor module (United States)

    Styles, Tim


    Most surveillance systems combine camera sensors with other detection sensors that trigger an alert to a human operator when an object is detected. The detection sensors typically require careful installation and configuration for each application and there is a significant burden on the operator to react to each alert by viewing camera video feeds. A demonstration system known as Sensing for Asset Protection with Integrated Electronic Networked Technology (SAPIENT) has been developed to address these issues using Autonomous Sensor Modules (ASM) and a central High Level Decision Making Module (HLDMM) that can fuse the detections from multiple sensors. This paper describes the 24 GHz radar based ASM, which provides an all-weather, low power and license exempt solution to the problem of wide area surveillance. The radar module autonomously configures itself in response to tasks provided by the HLDMM, steering the transmit beam and setting range resolution and power levels for optimum performance. The results show the detection and classification performance for pedestrians and vehicles in an area of interest, which can be modified by the HLDMM without physical adjustment. The module uses range-Doppler processing for reliable detection of moving objects and combines Radar Cross Section and micro-Doppler characteristics for object classification. Objects are classified as pedestrian or vehicle, with vehicle sub classes based on size. Detections are reported only if the object is detected in a task coverage area and it is classified as an object of interest. The system was shown in a perimeter protection scenario using multiple radar ASMs, laser scanners, thermal cameras and visible band cameras. This combination of sensors enabled the HLDMM to generate reliable alerts with improved discrimination of objects and behaviours of interest.

  13. Terahertz radar cross section measurements

    DEFF Research Database (Denmark)

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


    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 rad...... 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....

  14. Radar-based hail detection

    Czech Academy of Sciences Publication Activity Database

    Skripniková, Kateřina; Řezáčová, Daniela


    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

  15. Radar channel balancing with commutation

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter


    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.

  16. Interferometric millimeter wave and THz wave doppler radar

    Energy Technology Data Exchange (ETDEWEB)

    Liao, Shaolin; Gopalsami, Nachappa; Bakhtiari, Sasan; Raptis, Apostolos C.; Elmer, Thomas


    A mixerless high frequency interferometric Doppler radar system and methods has been invented, numerically validated and experimentally tested. A continuous wave source, phase modulator (e.g., a continuously oscillating reference mirror) and intensity detector are utilized. The intensity detector measures the intensity of the combined reflected Doppler signal and the modulated reference beam. Rigorous mathematics formulas have been developed to extract bot amplitude and phase from the measured intensity signal. Software in Matlab has been developed and used to extract such amplitude and phase information from the experimental data. Both amplitude and phase are calculated and the Doppler frequency signature of the object is determined.

  17. Chaos control and schedule of shuttle buses (United States)

    Nagatani, Takashi


    We study the dynamical behavior of a few shuttle buses when they pass each other freely and control the speed to retrieve the loading's delay. The dynamics of the buses is expressed in terms of the nonlinear maps. The tour times of buses and the time headway between buses exhibit the complex behavior with varying trips. The buses exhibit deterministic chaos even if there are no noises. Bus speeds up to retrieve the delay induced by loading the passengers on its bus. The bus chaos is controlled by varying the degree of speedup. The chaotic motion depends on both loading and speedup's parameters. The shuttle bus schedule is connected with the complex motions of shuttle buses. The region map (phase diagram) is shown to control the complex motions of buses.

  18. A perfect launch of Space Shuttle Discovery (United States)


    Space Shuttle Discovery lifts off Launch Pad 39A against a backdrop of xenon lights (just above the orbiter' nose and at left). On the Mobile Launcher Platform beneath, water begins flooding the area for flame and sound control. The perfect on- time liftoff occurred at 7:17 p.m. EDT, sending a crew of seven on the 100th launch in the history of the Shuttle program. Discovery carries a payload that includes the Integrated Truss Structure Z-1, first of 10 trusses that will form the backbone of the Space Station, and the third Pressurized Mating Adapter that will provide a Shuttle docking port for solar array installation on the sixth Station flight and Lab installation on the seventh Station flight. Discovery's landing is expected Oct. 22 at 2:10 p.m. EDT.

  19. A Shuttle Derived Vehicle launch system (United States)

    Tewell, J. R.; Buell, D. N.; Ewing, E. S.


    This paper describes a Shuttle Derived Vehicle (SDV) launch system presently being studied for the NASA by Martin Marietta Aerospace which capitalizes on existing Shuttle hardware elements to provide increased accommodations for payload weight, payload volume, or both. The SDV configuration utilizes the existing solid rocket boosters, external tank and the Space Shuttle main engines but replaces the manned orbiter with an unmanned, remotely controlled cargo carrier. This cargo carrier substitution more than doubles the performance capability of the orbiter system and is realistically achievable for minimal cost. The advantages of the SDV are presented in terms of performance and economics. Based on these considerations, it is concluded that an unmanned SDV offers a most attractive complement to the present Space Transportation System.

  20. Shuttle Case Study Collection Website Development (United States)

    Ransom, Khadijah S.; Johnson, Grace K.


    As a continuation from summer 2012, the Shuttle Case Study Collection has been developed using lessons learned documented by NASA engineers, analysts, and contractors. Decades of information related to processing and launching the Space Shuttle is gathered into a single database to provide educators with an alternative means to teach real-world engineering processes. The goal is to provide additional engineering materials that enhance critical thinking, decision making, and problem solving skills. During this second phase of the project, the Shuttle Case Study Collection website was developed. Extensive HTML coding to link downloadable documents, videos, and images was required, as was training to learn NASA's Content Management System (CMS) for website design. As the final stage of the collection development, the website is designed to allow for distribution of information to the public as well as for case study report submissions from other educators online.

  1. Radar imaging using statistical orthogonality (United States)

    Falconer, David G.


    Statistical orthogonality provides a mathematical basis for imaging scattering data with an inversion algorithm that is both robust and economic. The statistical technique is based on the approximate orthogonality of vectors whose elements are exponential functions with imaginary arguments and random phase angles. This orthogonality allows one to image radar data without first inverting a matrix whose dimensionality equals or exceeds the number of pixels or voxels in the algorithmic image. Additionally, statistical-based methods are applicable to data sets collected under a wide range of operational conditions, e.g., the random flight paths of the curvilinear SAR, the frequency-hopping emissions of ultra- wideband radar, or the narrowband data collected with a bistatic radar. The statistical approach also avoids the often-challenging and computationally intensive task of converting the collected measurements to a data format that is appropriate for imaging with a fast Fourier transform (FFT) or fast tomography algorithm (FTA), e.g., interpolating from polar to rectangular coordinates, or conversely.

  2. Space Radar Image of Salt Lake City, Utah (United States)


    This radar image of Salt Lake City, Utah, illustrates the different land use patterns that are present in the Utah Valley. Salt Lake City lies between the shores of the Great Salt Lake (the dark area on the left side of the image) and the Wasatch Front Range (the mountains in the upper half of the image). The Salt Lake City area is of great interest to urban planners because of the combination of lake, valley and alpine environments that coexist in the region. Much of the southern shore of the Great Salt Lake is a waterfowl management area. The green grid pattern in the right center of the image is Salt Lake City and its surrounding communities. The Salt Lake City airport is visible as the brown rectangle near the center of the image. Interstate Highway 15 runs from the middle right edge to the upper left of the image. The bright white patch east of Interstate 15 is the downtown area, including Temple Square and the state capitol. The University of Utah campus is the yellowish area that lies at the base of the mountains, east of Temple Square. The large reservoir in the lower left center is a mine tailings pond. The semi-circular feature in the mountains at the bottom edge of the image is the Kennecott Copper Mine. The area shown is 60 kilometers by 40 kilometers (37 miles by 25 miles) and is centered at 40.6 degrees north latitude, 112.0 degrees west longitude. North is toward the upper left. This image was acquired by the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) aboard the space shuttle Endeavour on April 10, 1994. The colors in this image represent the following radar channels and polarizations: red is L-band, horizontally transmitted and received; green is L-band, horizontally transmitted and vertically received; and blue is C-band, horizontally transmitted and 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.

  3. Space Radar Image of Central African Gorilla Habitat (United States)


    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

  4. STS-62 Space Shuttle mission report (United States)

    Fricke, Robert W., Jr.


    The STS-62 Space Shuttle Program Mission Report summarizes the Payload activities as well as the Orbiter, External Tank (ET), Solid Rocket Booster (SRB), Redesigned Solid Rocket Motor (RSRM), and the Space Shuttle main engine (SSHE) systems performance during the sixty-first flight of the Space Shuttle Program and sixteenth flight of the Orbiter vehicle Columbia (OV-102). In addition to the Orbiter, the flight vehicle consisted of an ET designated as ET-62; three SSME's which were designated as serial numbers 2031, 2109, and 2029 in positions 1, 2, and 3, respectively; and two SRB's which were designated BI-064. The RSRM's that were installed in each SRB were designated as 360L036A (lightweight) for the left SRB, and 36OWO36B (welterweight) for the right SRB. This STS-62 Space Shuttle Program Mission Report fulfills the Space Shuttle Program requirement as documented in NSTS 07700, Volume 8, Appendix E. That document requires that each major organizational element supporting the Program report the results of its hardware evaluation and mission performance plus identify all related in-flight anomalies. The primary objectives of the STS-62 mission were to perform the operations of the United States Microgravity Payload-2 (USMP-2) and the Office of Aeronautics and Space Technology-2 (OAST-2) payload. The secondary objectives of this flight were to perform the operations of the Dexterous End Effector (DEE), the Shuttle Solar Backscatter Ultraviolet/A (SSBUV/A), the Limited Duration Space Environment Candidate Material Exposure (LDCE), the Advanced Protein Crystal Growth (APCG), the Physiological Systems Experiments (PSE), the Commercial Protein Crystal Growth (CPCG), the Commercial Generic Bioprocessing Apparatus (CGBA), the Middeck Zero-Gravity Dynamics Experiment (MODE), the Bioreactor Demonstration System (BDS), the Air Force Maui Optical Site Calibration Test (AMOS), and the Auroral Photography Experiment (APE-B).

  5. Multiband radar characterization of forest biomes (United States)

    Dobson, M. Craig; Ulaby, Fawwaz T.


    The utility of airborne and orbital SAR in classification, assessment, and monitoring of forest biomes is investigated through analysis of orbital synthetic aperature radar (SAR) and multifrequency and multipolarized airborne SAR imagery relying on image tone and texture. Preliminary airborne SAR experiments and truck-mounted scatterometer observations demonstrated that the three dimensional structural complexity of a forest, and the various scales of temporal dynamics in the microwave dielectric properties of both trees and the underlying substrate would severely limit empirical or semi-empirical approaches. As a consequence, it became necessary to develop a more profound understanding of the electromagnetic properties of a forest scene and their temporal dynamics through controlled experimentation coupled with theoretical development and verification. The concatenation of various models into a physically-based composite model treating the entire forest scene became the major objective of the study as this is the key to development of a series of robust retrieval algorithms for forest biophysical properties. In order to verify the performance of the component elements of the composite model, a series of controlled laboratory and field experiments were undertaken to: (1) develop techniques to measure the microwave dielectric properties of vegetation; (2) relate the microwave dielectric properties of vegetation to more readily measured characteristics such as density and moisture content; (3) calculate the radar cross-section of leaves, and cylinders; (4) improve backscatter models for rough surfaces; and (5) relate attenuation and phase delays during propagation through canopies to canopy properties. These modeling efforts, as validated by the measurements, were incorporated within a larger model known as the Michigan Microwave Canopy Scattering (MIMICS) Model.

  6. IceBridge Snow Radar L1B Geolocated Radar Echo Strength Profiles V002 (United States)

    National Aeronautics and Space Administration — This data set contains radar echograms taken from the Center for Remote Sensing of Ice Sheets (CReSIS) ultra wide-band snow radar over land and sea ice in the Arctic...

  7. IceBridge Accumulation Radar L1B Geolocated Radar Echo Strength Profiles (United States)

    National Aeronautics and Space Administration — This data set contains radar echograms taken over Greenland and Antarctica using the Center for Remote Sensing of Ice Sheets (CReSIS) Accumulation Radar instrument....

  8. Simulation of a weather radar display for over-water airborne radar approaches (United States)

    Clary, G. R.


    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.

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

    DEFF Research Database (Denmark)

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


    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....

  10. IceBridge Snow Radar L1B Geolocated Radar Echo Strength Profiles (United States)

    National Aeronautics and Space Administration — This data set contains radar echograms taken from the Center for Remote Sensing of Ice Sheets (CReSIS) ultra wide-band snow radar over land and sea ice in the Arctic...

  11. IceBridge Accumulation Radar L1B Geolocated Radar Echo Strength Profiles (United States)

    National Aeronautics and Space Administration — This data set contains radar echograms taken over Greenland using the Center for Remote Sensing of Ice Sheets (CReSIS) Accumulation Radar instrument. The data were...

  12. Automotive Radar Sensors in Silicon Technologies

    CERN Document Server

    Jain, Vipul


    This book presents architectures and design techniques for mm-wave automotive radar transceivers. Several fully-integrated transceivers and receivers operating at 22-29 GHz and 77-81 GHz are demonstrated in both CMOS and SiGe BiCMOS technologies. Excellent performance is achieved indicating the suitability of silicon technologies for automotive radar sensors.  This book bridges an existing gap between information available on dependable system/architecture design and circuit design.  It provides the background of the field and detailed description of recent research and development of silicon-based radar sensors.  System-level requirements and circuit topologies for radar transceivers are described in detail. Holistic approaches towards designing radar sensors are validated with several examples of highly-integrated radar ICs in silicon technologies. Circuit techniques to design millimeter-wave circuits in silicon technologies are discussed in depth.  Describes concepts and fundamentals of automotive rada...

  13. Holography on the NASA Space Shuttle (United States)

    Wuerker, R. F.; Heflinger, L. O.; Flannery, J. V.; Kassel, A.; Rollauer, A. M.


    The SL-3 flight on the Space Shuttle will carry a 25 mW He-Ne laser holographic recorder for recording the solution growth of triglycine sulfate (TGS) crystals under low-zero gravity conditions. Three hundred holograms (two orthogonal views) will be taken (on SO-253 film) of each growth experiment. Processing and analysis (i.e., reconstructed imagery, holographic schlieren, reverse reference beam microscopy, and stored beam interferometry) of the holographic records will be done at NASA/MSFC. Other uses of the recorder on the Shuttle have been proposed.

  14. Radar Target Recognition Based on Stacked Denoising Sparse Autoencoder

    Directory of Open Access Journals (Sweden)

    Zhao Feixiang


    Full Text Available Feature extraction is a key step in radar target recognition. The quality of the extracted features determines the performance of target recognition. However, obtaining the deep nature of the data is difficult using the traditional method. The autoencoder can learn features by making use of data and can obtain feature expressions at different levels of data. To eliminate the influence of noise, the method of radar target recognition based on stacked denoising sparse autoencoder is proposed in this paper. This method can extract features directly and efficiently by setting different hidden layers and numbers of iterations. Experimental results show that the proposed method is superior to the K-nearest neighbor method and the traditional stacked autoencoder.

  15. The Comet Radar Explorer Mission (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


    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

  16. Radar range measurements in the atmosphere.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter


    The earths atmosphere affects the velocity of propagation of microwave signals. This imparts a range error to radar range measurements that assume the typical simplistic model for propagation velocity. This range error is a function of atmospheric constituents, such as water vapor, as well as the geometry of the radar data collection, notably altitude and range. Models are presented for calculating atmospheric effects on radar range measurements, and compared against more elaborate atmospheric models.

  17. Reduction of Stationary Clutter in Radar, (United States)


    coded passive interference (which consists of indivi- dual dipole packets dropped at certain intervals [2.30] and other stationary clutter present in...1958. 2.9. Cliquot, R. The band L radars of "type Orly". L’Onde Electrique , May 1961. 2.10. Decca Air Surveillance Radar DASR-! (Company catalogue...artificial obstacles in the form of a cloud of dipoles tuned 104 to the radar wavelength. As in the previous paragraph we will limit ourselves to a brief

  18. Spectrum Sharing Radar: Coexistence via Xampling


    Cohen, Deborah; Mishra, Kumar Vijay; Eldar, Yonina C.


    This paper presents a spectrum sharing technology enabling interference-free operation of a surveillance radar and communication transmissions over a common spectrum. A cognitive radio receiver senses the spectrum using low sampling and processing rates. The radar is a cognitive system that employs a Xampling-based receiver and transmits in several narrow bands. Our main contribution is the alliance of two previous ideas, CRo and cognitive radar (CRr), and their adaptation to solve the spectr...

  19. Comparação entre a Feição de Hidrografia Extraída de uma Imagem do Srtm (Shuttle Radar Topography Mission e a Vetorizada pelo Módulo Arcscan/ Arcgis®: : Estudo de Caso para Fins de Análise Hidrológica na Bacia Hidrográfica do Rio Grande, Divisa entre os Estados de MG e SP

    Directory of Open Access Journals (Sweden)

    Sady Júnior M. C. de Menezes


    Full Text Available O SRTM - Shutle Radar Topography Mission – é uma missão o qual gerou-se uma base topográfica digital de alta resolução. A SRTM consiste num sistema de radar especialmente modificado que voou a bordo do Endea-vour (ônibus espacial, em fevereiro de 2000. As imagens obtidas pelo SRTM garantiu amplas aplicações em estudos espaciais, uma vez que os processos de comunicação visual para a produção de cartografia de base e mapas de precisão da análise espacial foram utilizados. O presente estudo foi baseado em duas etapas de processamento de dados: inicialmente, incidiu sobre a manipulação de bases vetorizadas (dados de hidrografia obtidos pelo IBGE - Instituto Brasileiro de Geografia e Estatística e, em seguida, gerou-se informações vetorizadas a partir de imagens SRTM. A área de estudo é a Bacia do Rio Grande, MG/SP. Usando o programa de Sistemas de Informação Geográfica - ArcGIS 9.3.1 - foi obtido pelo módulo Spatial Analyst a hidrografia que foi extraída do SRTM. Após essa extração, foram comparadas as informações obtidas com o IBGE (vetor da base de dados utilizando o módulo Arcscan/ArcGIS e as informações obtidas pelo SRTM. Verificou-se uma ligeira diferença entre a distribuição e a concentração dos prováveis canais de drenagem entre os mapas dos vetores gerados (IBGE x SRTM. O trabalho demonstrou o uso dos dados do SRTM possibilitando a atualização de dados da rede hidrográfica de extensas áreas de modo bastante facilitado, com a vantagem de ser organizado pela mesma equipe e pelo mesmo processo metodológico, sem riscos de desigualdades durante sua geração.

  20. Radar reflection off extensive air showers

    Directory of Open Access Journals (Sweden)

    Werner F.


    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.

  1. Resonance and aspect matched adaptive radar (RAMAR)

    CERN Document Server

    Barrett, Terence William


    The book describes a new form of radar for which the target response is frequency, i.e., resonance-dependent. The book provides both prototype designs and empirical results collected from a variety of targets. The new form of radar, called RAMAR (Resonance and Aspect Matched Adaptive Radar) advances radar - mere ranging and detection - to the level of RF spectroscopy, and permits an advance of spectroscopic methods from optical, through infra-red and into the RF spectral range. The book will describe how a target's response can be a function of frequency components in the transmitted signal's

  2. Robust Sparse Sensing Using Weather Radar (United States)

    Mishra, K. V.; Kruger, A.; Krajewski, W. F.; Xu, W.


    The ability of a weather radar to detect weak echoes is limited by the presence of noise or unwanted echoes. Some of these unwanted signals originate externally to the radar system, such as cosmic noise, radome reflections, interference from co-located radars, and power transmission lines. The internal source of noise in microwave radar receiver is mainly thermal. The thermal noise from various microwave devices in the radar receiver tends to lower the signal-to-noise ratio, thereby masking the weaker signals. Recently, the compressed sensing (CS) technique has emerged as a novel signal sampling paradigm that allows perfect reconstruction of signals sampled at frequencies lower than the Nyquist rate. Many radar and remote sensing applications require efficient and rapid data acquisition. The application of CS to weather radars may allow for faster target update rates without compromising the accuracy of target information. In our previous work, we demonstrated recovery of an entire precipitation scene from its compressed-sensed version by using the matrix completion approach. In this study, we characterize the performance of such a CS-based weather radar in the presence of additive noise. We use a signal model where the precipitation signals form a low-rank matrix that is corrupted with (bounded) noise. Using recent advances in algorithms for matrix completion from few noisy observations, we reconstruct the precipitation scene with reasonable accuracy. We test and demonstrate our approach using the data collected by Iowa X-band Polarimetric (XPOL) weather radars.

  3. Ground Penetrating Radar : Ultra-wideband radars for improvised explosive devices and landmine detection

    NARCIS (Netherlands)

    Yarovoy, A.


    For last two decades Ultra-Wideband Ground Penetrating Radars seemed to be a useful tool for detection and classification of landmines and improvised explosive devices (IEDs). However limitations of radar technology considerably limited operational use of these radars. Recent research at TU Delft

  4. Radar Spectrum Engineering and Management (Ingenierie et gestion du spectre radar) (United States)


    industry, and academic experts in various facets of radar technology is needed to address the spectrum problems facing current (legacy) and future radar...Radar Applications”, IEEE International RF and Microwave Conference 2013, pp. 258-262, Penang, Malaysia , 9-11 December 2013. [88] A.A. Salah, R.S.A

  5. Radar network communication through sensing of frequency hopping (United States)

    Dowla, Farid; Nekoogar, Faranak


    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.

  6. Photonics-based broadband radar for high-resolution and real-time inverse synthetic aperture imaging. (United States)

    Zhang, Fangzheng; Guo, Qingshui; Wang, Ziqian; Zhou, Pei; Zhang, Guoqiang; Sun, Jun; Pan, Shilong


    A photonics-based radar with generation and de-chirp processing of broadband linear frequency modulated continuous-wave (LFMCW) signal in optical domain is proposed for high-resolution and real-time inverse synthetic aperture radar (ISAR) imaging. In the proposed system, a broadband LFMCW signal is generated by a photonic frequency quadrupler based on a single integrated electro-optical modulator, and the echoes reflected from the targets are de-chirped to a low frequency signal by a microwave photonic frequency mixer. The proposed radar can operate at a high frequency with a large bandwidth, and thus achieve an ultra-high range resolution for ISAR imaging. Thanks to the wideband photonic de-chirp technique, the radar receiver could apply low-speed analog-to-digital conversion and mature digital signal processing, which makes real-time ISAR imaging possible. A K-band photonics-based radar with an instantaneous bandwidth of 8 GHz (18-26 GHz) is established and its performance for ISAR imaging is experimentally investigated. Results show that a recorded two-dimensional imaging resolution of ~2 cm × ~2 cm is achieved with a sampling rate of 100 MSa/s in the receiver. Besides, fast ISAR imaging with 100 frames per second is verified. The proposed radar is an effective solution to overcome the limitations on operation bandwidth and processing speed of current radar imaging technologies, which may enable applications where high-resolution and real-time radar imaging is required.

  7. AMS gets lift on space shuttle Discovery

    CERN Multimedia


    AMS-02, the CERN-recognized experiment that will seek dark matter, missing matter and antimatter in Space aboard the International Space Station (ISS), has recently got the green light to be part of the STS-134 NASA mission in 2010. Installation of AMS detectors in the Prévessin experiment hall.In a recent press release, NASA announced that the last or last-but-one mission of the Space Shuttle programme would be the one that will deliver AMS, the Alpha Magnetic Spectrometer, to the International Space Station. The Space Shuttle Discovery is due to lift off in July 2010 from Kennedy Space Center and its mission will include the installation of AMS to the exterior of the space station, using both the shuttle and station arms. "It wasn’t easy to get a lift on the Space Shuttle from the Bush administration," says professor Samuel Ting, spokesperson of the experiment, "since during his administration all the funds for space research w...

  8. Rockwell Fails in Response to Shuttle Disaster. (United States)

    Kaufman, John A.


    Describes the contingent media relations policy employed by Rockwell International, the prime contractor for the United States space shuttle program, following the January 28, 1986, destruction of the Challenger. Analyzes Rockwell's response through a theoretical model of crisis perception and Rockwell's policy in relation to the mass media. (MS)

  9. Shuttle Transportation System Case-Study Development (United States)

    Ransom, Khadijah


    A case-study collection was developed for NASA's Space Shuttle Program. Using lessons learned and documented by NASA KSC engineers, analysts, and contractors, decades of information related to processing and launching the Space Shuttle was gathered into a single database. The goal was to provide educators with an alternative means to teach real-world engineering processes and to enhance critical thinking, decision making, and problem solving skills. Suggested formats were created to assist both external educators and internal NASA employees to develop and contribute their own case-study reports to share with other educators and students. Via group project, class discussion, or open-ended research format, students will be introduced to the unique decision making process related to Shuttle missions and development. Teaching notes, images, and related documents will be made accessible to the public for presentation of Space Shuttle reports. Lessons investigated included the engine cutoff (ECO) sensor anomaly which occurred during mission STS-114. Students will be presented with general mission infom1ation as well as an explanation of ECO sensors. The project will conclude with the design of a website that allows for distribution of information to the public as well as case-study report submissions from other educators online.

  10. Space Shuttle Mission Sequence-Illustration (United States)


    This diagram illustrates the Space Shuttle mission sequence. The Space Shuttle was approved as a national program in 1972 and developed through the 1970s. Part spacecraft and part aircraft, the Space Shuttle orbiter, the brain and the heart of the Space Transportation System (STS), required several technological advances, including thousands of insulating tiles able to stand the heat of reentry over the course of many missions, as well as sophisticated engines that could be used again and again without being thrown away. The airplane-like orbiter has three main engines, that burn liquid hydrogen and oxygen stored in the large external tank, the single largest structure in the Shuttle. Attached to the tank are two solid rocket boosters that provide the vehecile with most of the thrust needed for liftoff. Two minutes into the flight, the spent solids drop into the ocean to be recovered and refurbished for reuse, while the orbiter engines continue burning until approximately 8 minutes into the flight. After the mission is completed, the orbiter lands on a runway like an airplane.

  11. Shuttle Repair Tools Automate Vehicle Maintenance (United States)


    Successfully building, flying, and maintaining the space shuttles was an immensely complex job that required a high level of detailed, precise engineering. After each shuttle landed, it entered a maintenance, repair, and overhaul (MRO) phase. Each system was thoroughly checked and tested, and worn or damaged parts replaced, before the shuttle was rolled out for its next mission. During the MRO period, workers needed to record exactly what needed replacing and why, as well as follow precise guidelines and procedures in making their repairs. That meant traceability, and with it lots of paperwork. In 2007, the number of reports generated during electrical system repairs was getting out of hand-placing among the top three systems in terms of paperwork volume. Repair specialists at Kennedy Space Center were unhappy spending so much time at a desk and so little time actually working on the shuttle. "Engineers weren't spending their time doing technical work," says Joseph Schuh, an electrical engineer at Kennedy. "Instead, they were busy with repetitive, time-consuming processes that, while important in their own right, provided a low return on time invested." The strain of such inefficiency was bad enough that slow electrical repairs jeopardized rollout on several occasions. Knowing there had to be a way to streamline operations, Kennedy asked Martin Belson, a project manager with 30 years experience as an aerospace contractor, to co-lead a team in developing software that would reduce the effort required to document shuttle repairs. The result was System Maintenance Automated Repair Tasks (SMART) software. SMART is a tool for aggregating and applying information on every aspect of repairs, from procedures and instructions to a vehicle s troubleshooting history. Drawing on that data, SMART largely automates the processes of generating repair instructions and post-repair paperwork. In the case of the space shuttle, this meant that SMART had 30 years worth of operations

  12. A Dual Polarization, Active, Microstrip Antenna for an Orbital Imaging Radar System Operating at L-Band (United States)

    Kelly, Kenneth C.; Huang, John


    A highly successful Earth orbiting synthetic antenna aperture radar (SAR) system, known as the SIR-C mission, was carried into orbit in 1994 on a U.S. Shuttle (Space Transportation System) mission. The radar system was mounted in the cargo bay with no need to fold, or in any other way reduce the size of the antennas for launch. Weight and size were not limited for the L-Band, C-Band, and X-Band radar systems of the SIR-C radar imaging mission; the set of antennas weighed 10,500 kg, the L-Band antenna having the major share of the weight. This paper treats designing an L-Band antenna functionally similar to that used for SIR-C, but at a fraction of the cost and at a weight in the order of 250 kg. Further, the antenna must be folded to fit into the small payload shroud of low cost booster rocket systems. Over 31 square meters of antenna area is required. This low weight, foldable, electronic scanning antenna is for the proposed LightSAR radar system which is to be placed in Earth orbit on a small, dedicated space craft at the lowest possible cost for an efficient L- Band radar imaging system. This LightSAR spacecraft radar is to be continuously available for at least five operational years, and have the ability to map or repeat-map any area on earth within a few days of any request. A microstrip patch array, with microstrip transmission lines heavily employed in the aperture and in the corporate feed network, was chosen as the low cost approach for this active dual-polarization, 80 MHz (6.4%) bandwidth antenna design.

  13. A Parallel, High-Fidelity Radar Model (United States)

    Horsley, M.; Fasenfest, B.


    Accurate modeling of Space Surveillance sensors is necessary for a variety of applications. Accurate models can be used to perform trade studies on sensor designs, locations, and scheduling. In addition, they can be used to predict system-level performance of the Space Surveillance Network to a collision or satellite break-up event. A high fidelity physics-based radar simulator has been developed for Space Surveillance applications. This simulator is designed in a modular fashion, where each module describes a particular physical process or radar function (radio wave propagation & scattering, waveform generation, noise sources, etc.) involved in simulating the radar and its environment. For each of these modules, multiple versions are available in order to meet the end-users needs and requirements. For instance, the radar simulator supports different atmospheric models in order to facilitate different methods of simulating refraction of the radar beam. The radar model also has the capability to use highly accurate radar cross sections generated by the method of moments, accelerated by the fast multipole method. To accelerate this computationally expensive model, it is parallelized using MPI. As a testing framework for the radar model, it is incorporated into the Testbed Environment for Space Situational Awareness (TESSA). TESSA is based on a flexible, scalable architecture, designed to exploit high-performance computing resources and allow physics-based simulation of the SSA enterprise. In addition to the radar models, TESSA includes hydrodynamic models of satellite intercept and debris generation, orbital propagation algorithms, optical brightness calculations, optical system models, object detection algorithms, orbit determination algorithms, simulation analysis and visualization tools. Within this framework, observations and tracks generated by the new radar model are compared to results from a phenomenological radar model. In particular, the new model will be

  14. Shuttle SBUV (SSBUV) Solar Spectral Irradiance V008 (United States)

    National Aeronautics and Space Administration — The Shuttle Solar Backscatter Ultraviolet (SSBUV) level-2 irradiance data are available for eight space shuttle missions flown between 1989 and 1996. SSBUV, a...

  15. Ispitivanje uticaja oblaka smetnji na monoimpulsni nišanski radar i protivradarske rakete / Analysis of the influence of jamming clouds on monopulse tracking radars and antiradar missiles

    Directory of Open Access Journals (Sweden)

    Čedomir Gacović


    Full Text Available U ovom radu razmatrane su metodologije i eksperimentalni rezultati ispitivanja uticaja oblaka smetnji na monoimpulsne nišanske radare i protivradarske rakete. Rezultati su pokazali ispravnost postavljenih teorijskih modela i izvršenih analiza primene oblaka smetnji tokom NATO agresije na Jugoslaviju 1999. godine. / This paper considers the methods and the experimental results of the analysis of the jamming cloud influence on monopulse tracking radars and antiradar missiles. The results confirmed the value of the set theoretical models and the analyses of the application of jamming clouds carried out during the NATO aggression on Yugoslavia in 1999.

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

    Directory of Open Access Journals (Sweden)

    Nadia Maaref


    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.

  17. GPM Ground Validation Cloud Radar System (CRS) OLYMPEX V1 (United States)

    National Aeronautics and Space Administration — The GPM Ground Validation Cloud Radar System (CRS) OLYMPEX dataset provides radar reflectivity and Doppler velocity data collected during the Olympic Mountain...

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

    CERN Document Server

    Curry, G Richard


    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

  19. New Processing of Spaceborne Imaging Radar-C (SIR-C) Data (United States)

    Meyer, F. J.; Gracheva, V.; Arko, S. A.; Labelle-Hamer, A. L.


    The Spaceborne Imaging Radar-C (SIR-C) was a radar system, which successfully operated on two separate shuttle missions in April and October 1994. During these two missions, a total of 143 hours of radar data were recorded. SIR-C was the first multifrequency and polarimetric spaceborne radar system, operating in dual frequency (L- and C- band) and with quad-polarization. SIR-C had a variety of different operating modes, which are innovative even from today's point of view. Depending on the mode, it was possible to acquire data with different polarizations and carrier frequency combinations. Additionally, different swaths and bandwidths could be used during the data collection and it was possible to receive data with two antennas in the along-track direction.The United States Geological Survey (USGS) distributes the synthetic aperture radar (SAR) images as single-look complex (SLC) and multi-look complex (MLC) products. Unfortunately, since June 2005 the SIR-C processor has been inoperable and not repairable. All acquired SLC and MLC images were processed with a course resolution of 100 m with the goal of generating a quick look. These images are however not well suited for scientific analysis. Only a small percentage of the acquired data has been processed as full resolution SAR images and the unprocessed high resolution data cannot be processed any more at the moment.At the Alaska Satellite Facility (ASF) a new processor was developed to process binary SIR-C data to full resolution SAR images. ASF is planning to process the entire recoverable SIR-C archive to full resolution SLCs, MLCs and high resolution geocoded image products. ASF will make these products available to the science community through their existing data archiving and distribution system.The final paper will describe the new processor and analyze the challenges of reprocessing the SIR-C data.

  20. Indoor imagery with a 3D through-wall synthetic aperture radar (United States)

    Sévigny, Pascale; DiFilippo, David J.; Laneve, Tony; Fournier, Jonathan


    Through-wall radar imaging is an emerging technology with great interest to military and police forces operating in an urban environment. A through-wall imaging radar can potentially provide interior room layouts as well as detection and localization of targets of interest within a building. In this paper, we present our through-wall radar system mounted on the side of a vehicle and driven along a path in front of a building of interest. The vehicle is equipped with a LIDAR (Light Detection and Ranging) and motion sensors that provide auxiliary information. The radar uses an ultra wideband frequency-modulated continuous wave (FMCW) waveform to obtain high range resolution. Our system is composed of a vertical linear receive array to discriminate targets in elevation, and two transmit elements operated in a slow multiple-input multiple output (MIMO) configuration to increase the achievable elevation resolution. High resolution in the along-track direction is obtained through synthetic aperture radar (SAR) techniques. We present experimental results that demonstrate the 3-D capability of the radar. We further demonstrate target detection behind challenging walls, and imagery of internal wall features. Finally, we discuss future work.

  1. Notch Filter Analysis and Its Application in Passive Coherent Location Radar (in English

    Directory of Open Access Journals (Sweden)

    Li Ji-chuan


    Full Text Available The Normalized Least-Mean-Squares (NLMS algorithm is widely used to cancel the direct and multiple path interferences in Passive Coherent Location (PCL radar systems. This study proposes that the interference cancelation using the NLMS algorithm and the calculation of the radar Cross Ambiguity Function (CAF can be modeled as a notch filter, with the notch located at zero Doppler frequency in the surface of the radar CAF. The analysis shows that the notch’s width and depth are closely related to the step size of the NLMS algorithm. Subsequently, the effect of the notch in PCL radar target detection is analyzed. The results suggest that the detection performance of the PCL radar deteriorates because of the wide notch. Furthermore, the Nonuniform NLMS (NNLMS algorithm is proposed for removing the clutter with the Doppler frequency by using notch filtering. A step-size matrix is adopted to mitigate the low Doppler frequency clutter and lower the floor of the radar CAF. With the step-size matrix, can be obtained notches of different depths and widths in different range units of the CAF, which can filter the low Doppler frequency clutter. In addition, the convergence rate of the NNLMS algorithm is better than that of the traditional NLMS algorithm. The validity of the NNLMS algorithm is verified by experimental results.

  2. Mobile Ground-Based Radar Sensor for Localization and Mapping: An Evaluation of two Approaches

    Directory of Open Access Journals (Sweden)

    Damien Vivet


    Full Text Available This paper is concerned with robotic applications using a ground-based radar sensor for simultaneous localization and mapping problems. In mobile robotics, radar technology is interesting because of its long range and the robustness of radar waves to atmospheric conditions, making these sensors well-suited for extended outdoor robotic applications. Two localization and mapping approaches using data obtained from a 360° field of view microwave radar sensor are presented and compared. The first method is a trajectory-oriented simultaneous localization and mapping technique, which makes no landmark assumptions and avoids the data association problem. The estimation of the ego-motion makes use of the Fourier-Mellin transform for registering radar images in a sequence, from which the rotation and translation of the sensor motion can be estimated. The second approach uses the consequence of using a rotating range sensor in high speed robotics. In such a situation, movement combinations create distortions in the collected data. Velocimetry is achieved here by explicitly analysing these measurement distortions. As a result, the trajectory of the vehicle and then the radar map of outdoor environments can be obtained. The evaluation of experimental results obtained by the two methods is presented on real-world data from a vehicle moving at 30 km/h over a 2.5 km course.

  3. Radar Imaging and Target Identification (United States)


    charged to this contract for two years; in the last year only stipend and registration-in-absentia fees were charged. • Yi Fang, citizen of China ...Ferrara, Ph.D. May 2006, now in RYAT. Thesis title: "Radar Signal Process- ing". • Postdoc supported by China Scholarship Council: Dr. Ling Wang...on tt, so arc RT(X, X) and Rc{x, x). Furthermore, it follows that Ry, RT and Re are all supported on tt x fi. We use the notation RT and Tlc for

  4. Lunar radar mapping: Correlation between radar reflectivity and stratigraphy in north-western mare imbrium (United States)

    Schaber, G.G.; Eggleton, R.E.; Thompson, T.W.


    DELAY-DOPPLER radar maps of the Moon obtained with the 430 MHz (70 cm wavelength) radar of the Arecibo Ionospheric Observatory in Puerto Rico (Thompson, unpublished) are at present being studied to correlate geological information with the radar reflexion characteristics of the lunar surface. Preliminary evaluation of the radar data for the Sinus Iridum quadrangle (32??-48?? N; 14??-38?? W) has revealed that the lowest values of radar reflectivity are closely correlated with the mare materials of lowest albedo mapped by Schaber1 as of most recent volcanic origin. These radar data were obtained with a surface resolution of 50 to 100 km2 on January 24 and April 17, 1967. A detailed account of the delay-doppler radar mapping technique can be found in unpublished reports by Thompson. ?? 1970 Nature Publishing Group.

  5. Radar Detection of Layering in Ice: Experiments on a Constructed Layered Ice Sheet (United States)

    Carter, L. M.; Koenig, L.; Courville, Z.; Ghent, R. R.; Koutnik, M. R.


    The polar caps and glaciers of both Earth and Mars display internal layering that preserves a record of past climate. These layers are apparent both in optical datasets (high resolution images, core samples) and in ground penetrating radar (GPR) data. On Mars, the SHARAD (Shallow Radar) radar on the Mars Reconnaissance Orbiter shows fine layering that changes spatially and with depth across the polar caps. This internal layering has been attributed to changes in fractional dust contamination due to obliquity-induced climate variations, but there are other processes that can lead to internal layers visible in radar data. In particular, terrestrial sounding of ice sheets compared with core samples have revealed that ice density and composition differences account for the majority of the radar reflectors. The large cold rooms and ice laboratory facility at the U.S. Army Cold Regions Research and Engineering Laboratory (CRREL) provide us a unique opportunity to construct experimental ice sheets in a controlled setting and measure them with radar. In a CRREL laboratory, we constructed a layered ice sheet that is 3-m deep with a various snow and ice layers with known dust concentrations (using JSC Mars-1 basaltic simulant) and density differences. These ice sheets were profiled using a commercial GPR, at frequencies of 200, 400 and 900 MHz, to determine how the radar profile changes due to systematic and known changes in snow and ice layers, including layers with sub-wavelength spacing. We will report results from these experiments and implications for interpreting radar-detected layering in ice on Earth and Mars.

  6. A Proposal for an Operational HF Radar

    National Research Council Canada - National Science Library

    Gager, F. M; Guthrie, R. C; Headrick, J. M; Page, I. H; Zettle, E. N


    ... the USSR and the secondary purpose of detection of missile and ESV launchings. The radar system being proposed is based on the design of the Madre radar and the experience gained with the Madre installation at the NRL Chesapeake Bay Annex...

  7. Integration and Validation of Avian Radars (IVAR) (United States)


    organize its target data into an SQL database while relaying to user. Using same setup at ARTI as for PC3.1, demonstrate the RDS can, except for a...tracks from two radars with overlapping coverage The time references for two independent radars can be kept sufficiently in sync to support fusion

  8. Ultra-wideband radar sensors and networks

    Energy Technology Data Exchange (ETDEWEB)

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


    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.

  9. 46 CFR 184.404 - Radars. (United States)


    ... 46 Shipping 7 2010-10-01 2010-10-01 false Radars. 184.404 Section 184.404 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) VESSEL CONTROL AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Navigation Equipment § 184.404 Radars. (a) A vessel must be fitted with a...

  10. Synthetic aperture radar: principles and applications

    International Nuclear Information System (INIS)

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


    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)

  11. 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...

  12. High-precision positioning of radar scatterers

    NARCIS (Netherlands)

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


    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

  13. 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


    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

  14. Radar geology: Technology and program overview (United States)

    Barath, F. T.


    The state-of-the-art of active microwave remote sensors (altimeters, scatterometers and imagers) used in geologic applications is assessed and the ongoing radar geology activities within NASA, government agencies, industry, universities and foreign organizations is summarized. Plans for radar geology research and development and space flight missions are also outlined.

  15. A Scanning Microwave Radar and Radiometer

    DEFF Research Database (Denmark)

    Skou, Niels


    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...

  16. Quantitative Analysis of Radar Returns from Insects (United States)

    Riley, J. R.


    When a number of flying insects is low enough to permit their resolution as individual radar targets, quantitative estimates of their aerial density are developed. Accurate measurements of heading distribution using a rotating polarization radar to enhance the wingbeat frequency method of identification are presented.

  17. Joint Direction-of-Departure and Direction-of-Arrival Estimation in a UWB MIMO Radar Detecting Targets with Fluctuating Radar Cross Sections

    Directory of Open Access Journals (Sweden)

    Idnin Pasya


    Full Text Available This paper presents a joint direction-of-departure (DOD and direction-of-arrival (DOA estimation in a multiple-input multiple-output (MIMO radar utilizing ultra wideband (UWB signals in detecting targets with fluctuating radar cross sections (RCS. The UWB MIMO radar utilized a combination of two-way MUSIC and majority decision based on angle histograms of estimated DODs and DOAs at each frequency of the UWB signal. The proposed angle estimation scheme was demonstrated to be effective in detecting targets with fluctuating RCS, compared to conventional spectra averaging method used in subband angle estimations. It was found that a wider bandwidth resulted in improved estimation performance. Numerical simulations along with experimental evaluations in a radio anechoic chamber are presented.

  18. Methods of Attenuation Correction for the TRMM Precipitation Radar Data (United States)

    Meneghini, Robert; Iguchi, Toshio; Kozu, Toshiaki; Okamoto, Kenichi; Jones, Jeffrey; Liao, Liang


    The surface reference technique (SRT) has been studied extensively both theoretically and experimentally over the last decade. It is only with the launch of the Tropical Rain Measuring Mission (TRMM) Precipitation Radar, however, that we can begin to test directly whether the technique provides a reliable means of attenuation correction for spaceborne weather radars. Preliminary results indicate that the method yields results that are qualitatively reasonable when the rain rate is moderate or high and when the surface provides a stable reference value. The structure of the normalized radar cross section of the surface (NRCS), however, is highly complex in the sense that the statistics change with background type, incidence angle, location, and season. As a consequence of this, the reliability of the path attenuation estimate is not proportional simply to the amount of rain attenuation but to the rain attenuation relative to the inherent variability of the reference target. To illustrate the behavior of the SRT, several overpasses of the Hurricane Bonnie are shown. We also show that the proper choice of reference data set (spatial, temporal and global) can be critical to the success of the method.

  19. Clustered Multi-Task Learning for Automatic Radar Target Recognition. (United States)

    Li, Cong; Bao, Weimin; Xu, Luping; Zhang, Hua


    Model training is a key technique for radar target recognition. Traditional model training algorithms in the framework of single task leaning ignore the relationships among multiple tasks, which degrades the recognition performance. In this paper, we propose a clustered multi-task learning, which can reveal and share the multi-task relationships for radar target recognition. To further make full use of these relationships, the latent multi-task relationships in the projection space are taken into consideration. Specifically, a constraint term in the projection space is proposed, the main idea of which is that multiple tasks within a close cluster should be close to each other in the projection space. In the proposed method, the cluster structures and multi-task relationships can be autonomously learned and utilized in both of the original and projected space. In view of the nonlinear characteristics of radar targets, the proposed method is extended to a non-linear kernel version and the corresponding non-linear multi-task solving method is proposed. Comprehensive experimental studies on simulated high-resolution range profile dataset and MSTAR SAR public database verify the superiority of the proposed method to some related algorithms.

  20. Radar observations of asteroid 1986 JK (United States)

    Ostro, S. J.; Yeomans, D. K.; Chodas, P. W.; Goldstein, R. M.; Jurgens, R. F.; Thompson, T. W.


    The asteroid 1986 JK was observed with a 3.5 cm-wavelength radar in May and June, 1986, at less than 0.029 AU; its radar echo power circular polarization ratio indicates single backscattering from smooth surface elements. A working model constructed for the asteroid in light of these radar data postulates a 1-2 km object whose shape has little elongation and some polar flattening. Orbital and physical characteristics are rather cometlike. The radar astrometric data obtained are noted to be extremely powerful for orbit-improvement, so that a search ephemeris whose uncertainty is an order-of-magnitude smaller than that based on relevant optical data alone can be prepared by combining optical and radar data.

  1. Radar and sensor netting - Present and future (United States)

    Farina, A.; Studer, F. A.


    It is pointed out that a natural evolution of radar systems leads to the netting of radars dispersed on a certain portion of the surveillance space. The motivation for this evolution was provided by the possibility of fusing a great amount of data taken by radars operating independently. Multiradar tracking (MRT) represents a well-known system employed in civilian and military applications. The multistatic radar system is another well known netting concept. The present paper has the objective to provide some information regarding the potential of the netted system concepts. The netting of sensors other than radars is also promising, taking into account lasers, TV, radiometer, and acoustic devices. Attention is given to details concerning the multiradar system concept (the present), the multistatic system concept, wideband netting (the future), the multisensor system concept (the future), and artificial intelligence.

  2. Numerical simulation of imaging laser radar system (United States)

    Han, Shaokun; Lu, Bo; Jiang, Ming; Liu, Xunliang


    Rational and effective design of imaging laser radar systems is the key of imaging laser radar system research. Design must fully consider the interrelationship between various parameters. According to the parameters, choose suitable laser, detector and other components. To use of mathematical modeling and computer simulation is an effective imaging laser radar system design methods. This paper based on the distance equation, using the detection statistical methods, from the laser radar range coverage, detection probability, false-alarm rate, SNR to build the laser radar system mathematical models. In the process of setting up the mathematical models to fully consider the laser, atmosphere, detector and other factors on the performance that is to make the models be able to respond accurately the real situation. Based on this using C# and Matlab designed a simulation software.

  3. Meteor observation by the Kyoto meteor radar

    International Nuclear Information System (INIS)

    Kato, S.; Tsuda, T.


    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

  4. Weather radar rainfall data in urban hydrology

    DEFF Research Database (Denmark)

    Thorndahl, Søren; Einfalt, Thomas; Willems, Patrick


    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...

  5. Autonomous wireless radar sensor mote integrating a Doppler radar into a sensor mote and its application in surveillance and target material classification (United States)

    Iftekharuddin, Khan; Khan, Muhammad M. R.; McCracken, Ernest; Wang, Lan; Kozma, Robert


    An autonomous wireless sensor network that consists of different types of sensor modalities is a topic of intense research due to its versatility and portability of applications. Typical autonomous sensor networks commonly include passive sensor nodes such as infrared, acoustic, seismic, and magnetic. However, fusion of another active sensor such as Doppler radar in the integrated sensor network may offer powerful capabilities for many different sensing and classification tasks. In this work, we demonstrate the design and implementation of an autonomous wireless sensor network integrating a Doppler sensor into wireless sensor node with commercial off the shelf components. Then we demonstrate two applications of the newly integrated radar mote in a wireless sensor network environment where other sensor motes are supporting the integrated radar mote for autonomous triggering and data collection. At first we use the integrated system to detect the range and velocity of a toy train effectively to demonstrate its capability as a surveillance tool. Then we classify different types of non-conducting target materials based on their reflected signal response to newly built radar mote. Different types of materials can usually affect the amount of energy reflected back to the source of an electromagnetic wave. For investigating this observation we simulate models for the reflectivity of different homogeneous non-conducting materials using a mathematical model and later classify the types of target materials using real experimental data collected through our autonomous radar-mote sensor network.

  6. IoSiS: a radar system for imaging of satellites in space (United States)

    Jirousek, M.; Anger, S.; Dill, S.; Schreiber, E.; Peichl, M.


    Space debris nowadays is one of the main threats for satellite systems especially in low earth orbit (LEO). More than 700,000 debris objects with potential to destroy or damage a satellite are estimated. The effects of an impact often are not identifiable directly from ground. High-resolution radar images are helpful in analyzing a possible damage. Therefor DLR is currently developing a radar system called IoSiS (Imaging of Satellites in Space), being based on an existing steering antenna structure and our multi-purpose high-performance radar system GigaRad for experimental investigations. GigaRad is a multi-channel system operating at X band and using a bandwidth of up to 4.4 GHz in the IoSiS configuration, providing fully separated transmit (TX) and receive (RX) channels, and separated antennas. For the observation of small satellites or space debris a highpower traveling-wave-tube amplifier (TWTA) is mounted close to the TX antenna feed. For the experimental phase IoSiS uses a 9 m TX and a 1 m RX antenna mounted on a common steerable positioner. High-resolution radar images are obtained by using Inverse Synthetic Aperture Radar (ISAR) techniques. The guided tracking of known objects during overpass allows here wide azimuth observation angles. Thus high azimuth resolution comparable to the range resolution can be achieved. This paper outlines technical main characteristics of the IoSiS radar system including the basic setup of the antenna, the radar instrument with the RF error correction, and the measurement strategy. Also a short description about a simulation tool for the whole instrument and expected images is shown.

  7. Real-time windowing in imaging radar using FPGA technique (United States)

    Ponomaryov, Volodymyr I.; Escamilla-Hernandez, Enrique


    The imaging radar uses the high frequency electromagnetic waves reflected from different objects for estimating of its parameters. Pulse compression is a standard signal processing technique used to minimize the peak transmission power and to maximize SNR, and to get a better resolution. Usually the pulse compression can be achieved using a matched filter. The level of the side-lobes in the imaging radar can be reduced using the special weighting function processing. There are very known different weighting functions: Hamming, Hanning, Blackman, Chebyshev, Blackman-Harris, Kaiser-Bessel, etc., widely used in the signal processing applications. Field Programmable Gate Arrays (FPGAs) offers great benefits like instantaneous implementation, dynamic reconfiguration, design, and field programmability. This reconfiguration makes FPGAs a better solution over custom-made integrated circuits. This work aims at demonstrating a reasonably flexible implementation of FM-linear signal and pulse compression using Matlab, Simulink, and System Generator. Employing FPGA and mentioned software we have proposed the pulse compression design on FPGA using classical and novel windows technique to reduce the side-lobes level. This permits increasing the detection ability of the small or nearly placed targets in imaging radar. The advantage of FPGA that can do parallelism in real time processing permits to realize the proposed algorithms. The paper also presents the experimental results of proposed windowing procedure in the marine radar with such the parameters: signal is linear FM (Chirp); frequency deviation DF is 9.375MHz; the pulse width T is 3.2μs taps number in the matched filter is 800 taps; sampling frequency 253.125*106 MHz. It has been realized the reducing of side-lobes levels in real time permitting better resolution of the small targets.

  8. Analysis on Target Detection and Classification in LTE Based Passive Forward Scattering Radar. (United States)

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


    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.

  9. Shuttle Kit Freezer Refrigeration Unit Conceptual Design (United States)

    Copeland, R. J.


    The refrigerated food/medical sample storage compartment as a kit to the space shuttle orbiter is examined. To maintain the -10 F in the freezer kit, an active refrigeration unit is required, and an air cooled Stirling Cycle refrigerator was selected. The freezer kit contains two subsystems, the refrigeration unit, and the storage volume. The freezer must provide two basic capabilities in one unit. One requirement is to store 215 lbs of food which is consumed in a 30-day period by 7 people. The other requirement is to store 128.3 lbs of medical samples consisting of both urine and feces. The unit can be mounted on the lower deck of the shuttle cabin, and will occupy four standard payload module compartments on the forward bulkhead. The freezer contains four storage compartments.

  10. Shuttle Earth Views, 1994. Part 3 (United States)


    In this third part of a four-part video compilation of Space Shuttle Earth views, various geographical areas are shown, including both land and water masses. The views cover South America, Asia (North Vietnam, Laos, Cambodia, China, Malaysia, Thailand, Java, various islands, Burma, Philippines, Taiwan, Guam), New Guinea, Australia, Morocco, Southern Europe (Spain, Portugal, Algeria, Italy, Sicily, Greece, Former Republic of Yugoslavia, Tunisia), and parts of the Middle East (Libya, Saudi Arabia, Egypt, Israel, Jordan, Sinai, Cyprus, Lebanon, Iraq), the Pacific Ocean, the Atlantic Ocean, the Indian Ocean, and the Mediterranean, Dead, Coral, Tyrrhenian, Adriatic, Ionian, Red, South China, Mindanao, Arafura, Sulu, Java, and China Seas. Each film clip has a heading that names the shuttle and the geographical location of the footage.

  11. Radar

    DEFF Research Database (Denmark)

    Nielsen, Tom


    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...

  12. Space shuttle main engine vibration data base (United States)

    Lewallen, Pat


    The Space Shuttle Main Engine Vibration Data Base is described. Included is a detailed description of the data base components, the data acquisition process, the more sophisticated software routines, and the future data acquisition methods. Several figures and plots are provided to illustrate the various output formats accessible to the user. The numerous vibration data recall and analysis capabilities available through automated data base techniques are revealed.

  13. Monitoring tropical environments with Space Shuttle photography (United States)

    Helfert, Michael R.; Lulla, Kamlesh P.


    Orbital photography from the Space Shuttle missions (1981-88) and earlier manned spaceflight programs (1962-1975) allows remote sensing time series to be constructed for observations of environmental change in selected portions of the global tropics. Particular topics and regions include deforestation, soil erosion, supersedimentation in streams, lacustrine, and estuarine environments, and desertification in the greater Amazon, tropical Africa and Madagascar, South and Southeast Asia, and the Indo-Pacific archipelagoes.

  14. Shuttle Engine Designs Revolutionize Solar Power (United States)


    The Space Shuttle Main Engine was built under contract to Marshall Space Flight Center by Rocketdyne, now part of Pratt & Whitney Rocketdyne (PWR). PWR applied its NASA experience to solar power technology and licensed the technology to Santa Monica, California-based SolarReserve. The company now develops concentrating solar power projects, including a plant in Nevada that has created 4,300 jobs during construction.

  15. Adaptive synthetic aperture radar image enhancement (United States)

    Cheng, Hua; Tian, Jinwen


    An adaptive SAR image enhancement method is presented for reducing the speckle noise and increasing the contrast of synthetic aperture radar (SAR) images. First, a fuzzy logic based filter, employing fuzzy edge to weight the contributions of pixel values in filter window, is used to filter the speckles. Second, the original SAR image is decomposed into lowfrequency component and high-frequency component. The fuzzy filtered image is viewed as the low-frequency component, and the contrast limited adaptive histogram equalization algorithm is used to increase its contrast. The highfrequency component is obtained by subtracting the low-frequency component from the original image, and its gain is controlled by fuzzy structural which employed to express the degree of a pixel belonging to structures. After processed one after the other, the two components are added together to form the final enhanced SAR image. Experimental results show the excellent effect of the proposed method by visual observation and numerical measurement. Many fine structures and little speckle noise can be seen from the enhanced SAR images.

  16. Nuclear powered satellite design for shuttle launches

    International Nuclear Information System (INIS)

    Kaplan, M.H.


    Developing technology and the transition period of the late 1970's from expendable launchers to reusable space shuttles and from single satellite designs to standardized and modularized configurations represent a strong motivation and unique opportunity to actively investigate new applications of nuclear power for satellites. Recently, the U.S. Energy Research and Development Administration has initiated studies on various aspects of nuclear powered satellite design and mission problems in order to establish the viability of using such power supplies for future space missions. The work reported here deals primarily with the 100 to 2,000 We power range and consists of many faceted effort. Spacecraft design problems associated with integration of nuclear power are addressed. Launch constraints and interfaces with respect to the space shuttle and those peculiar to nuclear powered vehicles are considered. Design of isotope power generators from an overall mission point of view is considered. A point design exercise is included to illustrate a specific application. Three primary aspects of nuclear powered satellite philosophy are considered. These include space shuttle capabilities, spacecraft design, and power supply design

  17. Orbital Debris Shape and Orientation Effects on Impact Damage to Shuttle Tiles (United States)

    Evans, Steven W.; Williamsen, Joel


    Taking the damage results from a previous paper as a guide, and using a tile model created for the STS-107 accident investigation, we used the SPHC hydrodynamic code to evaluate the probable worst-case impact effects of flat, rectangular, "flake-shaped," orbital debris particles on Space Shuttle thermal tiles. We compared the damage from flakes with that produced by spheres. The flakes and spheres were sized according to a "characteristic length" (Lc) derived from radar cross-section measurements, and embodied in the NASA Standard Breakup Model (SBM). Impacts were simulated at near-normal obliquity, at 12 km/sec. We modeled the worst-case flake orientation: a corner-on impact, an orientation we term a "Face A-B" impact. Results of our simulations indicate that flake impactors are less damaging than spheres of the same Lc. Since spherical impactors have been assumed in analyses of shuttle orbital debris impact risk, we find that these risks may have been overestimated. This work represents a preliminary second step, i.e., a follow-on to [1], in developing a sensitivity analysis for the expected range of effects on damage considering spherical vs. non-spherical impactors, as recommended by the Institute for Defense Analyses (IDA) report to the Columbia Accident Investigation Board.

  18. Advanced Signal Analysis for Forensic Applications of Ground Penetrating Radar

    Energy Technology Data Exchange (ETDEWEB)

    Steven Koppenjan; Matthew Streeton; Hua Lee; Michael Lee; Sashi Ono


    Ground penetrating radar (GPR) systems have traditionally been used to image subsurface objects. The main focus of this paper is to evaluate an advanced signal analysis technique. Instead of compiling spatial data for the analysis, this technique conducts object recognition procedures based on spectral statistics. The identification feature of an object type is formed from the training vectors by a singular-value decomposition procedure. To illustrate its capability, this procedure is applied to experimental data and compared to the performance of the neural-network approach.

  19. Shaded Relief and Radar Image with Color as Height, Madrid, Spain (United States)


    The white, mottled area in the right-center of this image from NASA's Shuttle Radar Topography Mission (SRTM) is Madrid, the capital of Spain. Located on the Meseta Central, a vast plateau covering about 40 percent of the country, this city of 3 million is very near the exact geographic center of the Iberian Peninsula. The Meseta is rimmed by mountains and slopes gently to the west and to the series of rivers that form the boundary with Portugal. The plateau is mostly covered with dry grasslands, olive groves and forested hills.Madrid is situated in the middle of the Meseta, and at an elevation of 646 meters (2,119 feet) above sea level is the highest capital city in Europe. To the northwest of Madrid, and visible in the upper left of the image, is the Sistema Central mountain chain that forms the 'dorsal spine' of the Meseta and divides it into northern and southern subregions. Rising to about 2,500 meters (8,200 feet), these mountains display some glacial features and are snow-capped for most of the year. Offering almost year-round winter sports, the mountains are also important to the climate of Madrid.Three visualization methods were combined to produce this image: shading and color coding of topographic height and radar image intensity. The shade image was derived by computing topographic slope in the northwest-southeast direction. North-facing slopes appear bright and south-facing slopes appear dark. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow and brown to white at the highest elevations. The shade image was combined with the radar intensity image in the flat areas.Elevation data used in this image was acquired by the SRTM aboard the Space Shuttle Endeavour, launched on Feb. 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

  20. The derivation of sub-canopy surface terrain models of coastal forests using synthetic aperture radar (United States)

    Imhoff, M. L.; Gesch, D. B.


    Radar data acquired by the Shuttle Imaging Radar-B mission covering a portion of the Mouths of the Ganges forests were used to create a terrain model for use in determining tidal flow and eventual nutrient transport from the forest to the marine habitat. Results show that good digital topographic terrain models of wet coastal forests can be generated using multiple sets of L-band SAR and ancillary tide elevation data. The dominance of the interaction phenomenon in the radar backscatter of flooded forests can be used to create sub-canopy inundation maps which when merged with tide surface data can be used to generate reasonable topographic models. Ideally models could be improved by using multiple sets of data at a constant incidence angle over the total tide range. The optimal angle for the SAR depends upon the characteristics of the forest. The range of 46 to 57 deg seems applicable to the 12.5 m tall closed canopy in this example. Such models can be an extremely valuable tool for studying and mapping the mangal ecosystem.

  1. An atlas of November 1978 synthetic aperture radar digitized imagery for oil spill studies (United States)

    Maurer, H. E.; Oderman, W.; Crosswell, W. F.


    A data set is described which consists of digitized synthetic aperture radar (SAR) imagery plus correlative data and some preliminary analysis results. This data set should be of value to experimenters who are interested in the SAR instrument and its application to the detection and monitoring of oil on water and other distributed targets.

  2. New look at radar auroral motions

    International Nuclear Information System (INIS)

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


    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

  3. Using phase for radar scatterer classification (United States)

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


    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.

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

    CERN Document Server

    Davis, Mark


    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).

  5. The use of radar for bathymetry in shallow seas

    NARCIS (Netherlands)

    Greidanus, H.


    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

  6. Decision Tool for optimal deployment of radar systems

    NARCIS (Netherlands)

    Vogel, M.H.


    A Decision Tool for air defence is presented. This Decision Tool, when provided with information about the radar, the environment, and the expected class of targets, informs the radar operator about detection probabilities. This assists the radar operator to select the optimum radar parameters. n

  7. Advanced Architectures for Modern Weather/Multifunction Radars (United States)


    Advanced Architectures for Modern Weather /Multifunction Radars Caleb Fulton The University of Oklahoma Advanced Radar Research Center Norman...and all of them are addressing the need to lower cost while improving beamforming flexibility in future weather radar systems that will be tasked...with multiple non- weather functions. Keywords: Phased arrays, digital beamforming, multifunction radar . Introduction and Overview As the performance

  8. Microbiological Lessons Learned from the Space Shuttle (United States)

    Pierson, Duane L.; Ott, C. Mark; Bruce, Rebekah; Castro, Victoria A.; Mehta, Satish K.


    After 30 years of being the centerpiece of NASA s human spacecraft, the Space Shuttle will retire. This highly successful program provided many valuable lessons for the International Space Station (ISS) and future spacecraft. Major microbiological risks to crewmembers include food, water, air, surfaces, payloads, animals, other crewmembers, and ground support personnel. Adverse effects of microorganisms are varied and can jeopardize crew health and safety, spacecraft systems, and mission objectives. Engineering practices and operational procedures can minimize the negative effects of microorganisms. To minimize problems associated with microorganisms, appropriate steps must begin in the design phase of new spacecraft or space habitats. Spacecraft design must include requirements to control accumulation of water including humidity, leaks, and condensate on surfaces. Materials used in habitable volumes must not contribute to microbial growth. Use of appropriate materials and the implementation of robust housekeeping that utilizes periodic cleaning and disinfection will prevent high levels of microbial growth on surfaces. Air filtration can ensure low levels of bioaerosols and particulates in the breathing air. The use of physical and chemical steps to disinfect drinking water coupled with filtration can provide safe drinking water. Thorough preflight examination of flight crews, consumables, and the environment can greatly reduce pathogens in spacecraft. The advances in knowledge of living and working onboard the Space Shuttle formed the foundation for environmental microbiology requirements and operations for the International Space Station (ISS) and future spacecraft. Research conducted during the Space Shuttle Program resulted in an improved understanding of the effects of spaceflight on human physiology, microbial properties, and specifically the host-microbe interactions. Host-microbe interactions are substantially affected by spaceflight. Astronaut immune

  9. Analysis of the extinction effect on precipitation measurements with C-Band Radar by means of simulation and measurement; Analyse des Extinktionseffektes bei Niederschlagsmessungen mit einem C-Band Radar anhand von Simulation und Messung

    Energy Technology Data Exchange (ETDEWEB)

    Blahak, U.


    The extinction of microwave energy by hydrometeors is an error source when interpreting radar precipitation measurements quantitatively. Energy is constantly detracted from a travelling radar pulse, which ultimately leeds to an underestimation of the precipitation intensity. Correction procedures proposed in literature mostly rely on the assumption of a well-defined relation between radar reflectivity and extinction which is valid on average for rain; those algorithms often proof to be unstable. With regard to that, the present thesis deals with the variability of extinction for given radar reflectivity (taking into account different precipitation types, including melting particles), since this can be an important source of the abovementioned instability. First, theoretical methods are applied (Mie-scattering, effective complex refractive index for melting hydrometeors). Those calculations suffer from a lot of uncertainties. Therefore, extinction parameters are derived experimentally as well, using measurements of two radars whose measuring volumes overlap. To this end, a new dual radar method was developed, which tries to take into account the various error sources in the best possible way. As a result, it is found that the extinction of microwaves by hydrometeors is extremely variable for given radar reflectivity, which has important consequences for the development of correction procedures. (orig.)

  10. B-52 Testing Developmental Space Shuttle Drag Chute (United States)


    An experimental drag chute deploys amidst a cloud of dust behind NASA's B-52 research aircraft just after landing on Rogers Dry Lake, adjacent to the Dryden Flight Research Center, Edwards, California, on a 1990 research flight. The B-52's tests led to the development of a drag chute to help the Space Shuttle land more safely and easily. NASA B-52, Tail Number 008, is an air launch carrier aircraft, 'mothership,' as well as a research aircraft platform that has been used on a variety of research projects. The aircraft, a 'B' model built in 1952 and first flown on June 11, 1955, is the oldest B-52 in flying status and has been used on some of the most significant research projects in aerospace history. Some of the significant projects supported by B-52 008 include the X-15, the lifting bodies, HiMAT (highly maneuverable aircraft technology), Pegasus, validation of parachute systems developed for the space shuttle program (solid-rocket-booster recovery system and the orbiter drag chute system), and the X-38. The B-52 served as the launch vehicle on 106 X-15 flights and flew a total of 159 captive-carry and launch missions in support of that program from June 1959 to October 1968. Information gained from the highly successful X-15 program contributed to the Mercury, Gemini, and Apollo human spaceflight programs as well as space shuttle development. Between 1966 and 1975, the B-52 served as the launch aircraft for 127 of the 144 wingless lifting body flights. In the 1970s and 1980s, the B-52 was the launch aircraft for several aircraft at what is now the Dryden Flight Research Center, Edwards, California, to study spin-stall, high-angle-of attack, and maneuvering characteristics. These included the 3/8-scale F-15/spin research vehicle (SRV), the HiMAT (Highly Maneuverable Aircraft Technology) research vehicle, and the DAST (drones for aerodynamic and structural testing). The aircraft supported the development of parachute recovery systems used to recover the space

  11. Radar signal processing and its applications

    CERN Document Server

    Hummel, Robert; Stoica, Petre; Zelnio, Edmund


    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.

  12. Marine radar properties, analysis and applications


    Kaspersen, Kai Magne


    In this thesis marine radars are compared with synthetic aperture radars (SAR) and the possibility of cross-over applications are investigated. A first cross-over has been demonstrated by using the TS-CFAR on marine radar images. The TS-CFAR was originally developed for SAR and is a constant false alarm rate (CFAR) detection algorithm based on truncated statistics. Detecting weak targets embedded in sea clutter is difficult because it is hard to find a model describing the sea in its various ...

  13. Radar, sonar, and holography an introduction

    CERN Document Server

    Kock, Winston E


    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

  14. Synthetic Data for Testing TRMM Radar Algorithms (United States)

    Jones, Jeffrey A.; Meneghini, Robert; Iguchi, Toshio; Tao, Wei-Kuo


    Test data are required to test algorithms for the TRMM Precipitation Radar. These data are needed to test the design of the computer codes under development for the operational phase of the mission, and also to test and evaluate alternative or improved precipitation retrieval algorithms. Over a number of years we have developed and used a 3-dimensional radar model for simulating spaceborne precipitation radars. We have adapted this code to produce data files as close as possible to the TRMM file specifications. In this paper, we will describe the model as it is currently implemented, and show some samples of the synthetic data sets.

  15. New Vacuum Electronic Devices for Radar

    Directory of Open Access Journals (Sweden)

    Hu Yinfu


    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.

  16. The Italian involvement in Cassini radar (United States)

    Nirchio, F.; Pernice, B.; Borgarelli, L.; Dionisio, C.


    The Radio Frequency Electronic Subsystem (RFES) of the Cassini radar is described. The requirements of the Cassini radar are summarized. The design parameters taken into consideration in developing the RFES are described. The RFES interfaces with the High Gain Antenna (HGA) for signal transmission and reception. The operational parameters of the Cassini radar are presented. The front end electronics (FEE), microwave receiver (MR), high power amplifier (HPA), frequency generator (FG), digital chip generator (DCG), Chirp Up Converter and Amplifier (CUCA) and power supply of the RFES are described.

  17. A 35-GHz radar for sensing applications (United States)

    Park, J. S.; Nguyen, C.


    We report a millimeter-wave stepped-frequency radar operating from 29.72 to 37.7 GHz for sensing applications. The radar is implemented using coherent super-heterodyne scheme and completely realized using microwave and millimeterwave integrated circuits. The developed radar has been demonstrated for different sensing applications with high accuracy and resolution. It can be used for various sensing applications including pavement and bridge assessment, liquid-level measurement, detection and location of buried mines and unexploded ordnance (UXO), detection of intrusion to structures including important civil facilities, detection of slow moving objects, surveillance and monitoring of hidden activities and objects.

  18. Radar Exploration of Cometary Nuclei (United States)

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


    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.

  19. Metal-wool heat shields for space shuttle. [design, fabrication, and attachment to structure (United States)

    Miller, R. C.; Clure, J. L.


    The packaging of metal wool for reusable thermal heat shields applied to aerodynamic and other surfaces for the space shuttle was analyzed and designed, and samples were fabricated and experimentally studied. Parametric trends were prepared for selected configurations. An all-metal thermally efficient, reliable, reusable and producible heat shield system was designed and structurally tested for use on spacecraft aerodynamic surfaces where temperatures do not exceed 810 K. Stainless steel sheet, primarily for structure and secondarily in the transverse plane for thermal expansion, was shown to accommodate thermal expansion in all directions when restrained at the edges and heated to 1360 K. Aerodynamic loads of 0.35 x 1000,000 newtons/sq meter, and higher, may be easily accepted by structures of this design. Seven all-metal thermal protection specimens, 12.7 cm square and 2.5 cm thick were fabricated and are being experimentally evaluated at simulated shuttle entry conditions in an arc jet facility.

  20. CERN Shuttles - NEW Regular Shuttle Services as from 11/01/2010

    CERN Multimedia

    GS Department


    As of Monday 11 January a new regular shuttle service (from Monday to Friday) will be available to facilitate transportation: Within and between both CERN sites, Meyrin and Prevessin; To and from the following LHC points: ATLAS, ALICE, CMS, LHCb. For further details, please consult the timetable for this service. We should also like to take this opportunity to encourage you to use the new regular TPG Y bus service rather than the special on-demand CERN transport service to and from Geneva Airport whenever possible. The TPG buses run from 06:00 to 00:30. For further details, please consult the TPG timetable. Please do not hesitate to give us your feedback on the shuttle services: e-mail to In case of problems with the shuttles, please contact 75411. GS-SEM Group Infrastructure and General Services Department

  1. First upper limits on the radar cross section of cosmic-ray induced extensive air showers (United States)

    Abbasi, R. U.; Abe, M.; Abou Bakr Othman, M.; Abu-Zayyad, T.; Allen, M.; Anderson, R.; Azuma, R.; Barcikowski, E.; Belz, J. W.; Bergman, D. R.; Besson, D.; Blake, S. A.; Byrne, M.; Cady, R.; Chae, M. J.; Cheon, B. G.; Chiba, J.; Chikawa, M.; Cho, W. R.; Farhang-Boroujeny, B.; Fujii, T.; Fukushima, M.; Gillman, W. H.; Goto, T.; Hanlon, W.; Hanson, J. C.; Hayashi, Y.; Hayashida, N.; Hibino, K.; Honda, K.; Ikeda, D.; Inoue, N.; Ishii, T.; Ishimori, R.; Ito, H.; Ivanov, D.; Jayanthmurthy, C.; Jui, C. C. H.; Kadota, K.; Kakimoto, F.; Kalashev, O.; Kasahara, K.; Kawai, H.; Kawakami, S.; Kawana, S.; Kawata, K.; Kido, E.; Kim, H. B.; Kim, J. H.; Kim, J. H.; Kitamura, S.; Kitamura, Y.; Kunwar, S.; Kuzmin, V.; Kwon, Y. J.; Lan, J.; Lim, S. I.; Lundquist, J. P.; Machida, K.; Martens, K.; Matsuda, T.; Matsuyama, T.; Matthews, J. N.; Minamino, M.; Mukai, K.; Myers, I.; Nagasawa, K.; Nagataki, S.; Nakamura, T.; Nonaka, T.; Nozato, A.; Ogio, S.; Ogura, J.; Ohnishi, M.; Ohoka, H.; Oki, K.; Okuda, T.; Ono, M.; Oshima, A.; Ozawa, S.; Park, I. H.; Prohira, S.; Pshirkov, M. S.; Rezazadeh-Reyhani, A.; Rodriguez, D. C.; Rubtsov, G.; Ryu, D.; Sagawa, H.; Sakurai, N.; Sampson, A. L.; Scott, L. M.; Schurig, D.; Shah, P. D.; Shibata, F.; Shibata, T.; Shimodaira, H.; Shin, B. K.; Smith, J. D.; Sokolsky, P.; Springer, R. W.; Stokes, B. T.; Stratton, S. R.; Stroman, T. A.; Suzawa, T.; Takai, H.; Takamura, M.; Takeda, M.; Takeishi, R.; Taketa, A.; Takita, M.; Tameda, Y.; Tanaka, H.; Tanaka, K.; Tanaka, M.; Thomas, S. B.; Thomson, G. B.; Tinyakov, P.; Tkachev, I.; Tokuno, H.; Tomida, T.; Troitsky, S.; Tsunesada, Y.; Tsutsumi, K.; Uchihori, Y.; Udo, S.; Urban, F.; Vasiloff, G.; Venkatesh, S.; Wong, T.; Yamane, R.; Yamaoka, H.; Yamazaki, K.; Yang, J.; Yashiro, K.; Yoneda, Y.; Yoshida, S.; Yoshii, H.; Zollinger, R.; Zundel, Z.


    TARA (Telescope Array Radar) is a cosmic ray radar detection experiment colocated with Telescope Array, the conventional surface scintillation detector (SD) and fluorescence telescope detector (FD) near Delta, Utah, U.S.A. The TARA detector combines a 40 kW, 54.1 MHz VHF transmitter and high-gain transmitting antenna which broadcasts the radar carrier over the SD array and within the FD field of view, towards a 250 MS/s DAQ receiver. TARA has been collecting data since 2013 with the primary goal of observing the radar signatures of extensive air showers (EAS). Simulations indicate that echoes are expected to be short in duration (∼ 10 μs) and exhibit rapidly changing frequency, with rates on the order 1 MHz/μs. The EAS radar cross-section (RCS) is currently unknown although it is the subject of over 70 years of speculation. A novel signal search technique is described in which the expected radar echo of a particular air shower is used as a matched filter template and compared to waveforms obtained by triggering the radar DAQ using the Telescope Array fluorescence detector. No evidence for the scattering of radio frequency radiation by EAS is obtained to date. We report the first quantitative RCS upper limits using EAS that triggered the Telescope Array Fluorescence Detector. The transmitter is under the direct control of experimenters, and in a radio-quiet area isolated from other radio frequency (RF) sources. The power and radiation pattern are known at all times. Forward power up to 40 kW and gain exceeding 20 dB maximize energy density in the radar field. Continuous wave (CW) transmission gives 100% duty cycle, as opposed to pulsed radar. TARA utilizes a high sample rate DAQ (250 MS/s). TARA is colocated with a large state-of-the-art conventional CR observatory, allowing the radar data stream to be sampled at the arrival times of known cosmic ray events. Each of these attributes of the TARA detector has been discussed in detail in the literature [8]. A map

  2. Experimental simulation of retrodirective cross-eye jamming

    CSIR Research Space (South Africa)

    Du Plessis, WP


    Full Text Available Experimental measurements that accurately simulate the effect of a retrodirective cross-eye jammer on a monopulse radar are described. The accuracy of a recently published extended analysis of retrodirective crosseye jamming and the limitations...

  3. A Short Distance CW-Radar Sensor at 77 GHz in LTCC for Industrial Applications (United States)

    Rusch, Christian; Klein, Tobias; Beer, Stefan; Zwick, Thomas


    The paper presents a Continuous-Wave(CW)-Radar sensor for high accuracy distance measurements in industrial applications. The usage of radar sensors in industrial scenarios has the advantage of a robust functionality in wet or dusty environments where optical systems reach their limits. This publication shows that accuracies of a few micro-meters are possible with millimeter-wave systems. In addition to distance measurement results the paper describes the sensor concept, the experimental set-up with the measurement process and possibilities to increase the accuracy even further.

  4. Development Of Signal Detection For Radar Navigation System


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


    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...

  5. Application of MIMO Techniques in sky-surface wave hybrid networking sea-state radar system (United States)

    Zhang, L.; Wu, X.; Yue, X.; Liu, J.; Li, C.


    . The field experimental results show the presented method is effective. The echoes are obvious and distinguishable both in co-located MIMO mode and widely distributed MIMO mode. Key words: sky-surface wave hybrid networking; sea-state radar; MIMO; phase-coded

  6. 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


    ...: 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...

  7. The design of infrared laser radar for vehicle initiative safety (United States)

    Gong, Ping; Xu, Xi-ping; Li, Xiao-yu; Li, Tian-zhi; Liu, Yu-long; Wu, Jia-hui


    Laser radar for vehicle is mainly used in advanced vehicle on-board active safety systems, such as forward anti-collision systems, active collision warning systems and adaptive cruise control systems, etc. Laser radar for vehicle plays an important role in the improvement of vehicle active safety and the reduction of traffic accidents. The stability of vehicle active anti-collision system in dynamic environment is still one of the most difficult problems to break through nowadays. According to people's driving habit and the existed detecting technique of sensor, combining the infrared laser range and galvanometer scanning technique , design a 3-D infrared laser radar which can be used to assist navigation, obstacle avoidance and the vehicle's speed control for the vehicle initiative safety. The device is fixed to the head of vehicle. Then if an accident happened, the device could give an alarm to remind the driver timely to decelerate or brake down, by which way can people get the purpose of preventing the collision accidents effectively. To accomplish the design, first of all, select the core components. Then apply Zemax to design the transmitting and receiving optical system. Adopt 1550 nm infrared laser transmitter as emission unit in the device, a galvanometer scanning as laser scanning unit and an InGaAs-APD detector as laser echo signal receiving unit. Perform the construction of experimental system using FPGA and ARM as the core controller. The system designed in this paper can not only detect obstacle in front of the vehicle and make the control subsystem to execute command, but also transfer laser data to PC in real time. Lots of experiments using the infrared laser radar prototype are made, and main performance of it is under tested. The results of these experiments show that the imaging speed of the laser radar can reach up to 25 frames per second, the frame resolution of each image can reach 30×30 pixels, the horizontal angle resolution is about 6. 98

  8. Ground penetrating radar (GPR) analysis : Phase I. (United States)


    "The objective of this work is to evaluate the feasibility of expanding the MDT's Ground Penetrating : Radar (GPR) program to a broader range of pavement evaluation activities. Currently, MDT uses GPR in : conjunction with its Falling Weight Deflecto...

  9. Airborne Radar Search for Diesel Submarines (ARSDS)

    National Research Council Canada - National Science Library

    Pilnick, Steven E; Landa, Jose


    .... 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...

  10. Airborne Radar Search for Diesel Submarines

    National Research Council Canada - National Science Library

    Pilnick, Steven E; Landa, Jose


    .... 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...

  11. Bird Migration Echoes Observed by Polarimetric Radar


    MINDA, Haruya; FURUZAWA, Fumie A.; SATOH, Shinsuke; NAKAMURA, Kenji


    A C-band polarimetric radar on Okinawa Island successfully observed large-scale bird migrations over the western Pacific Ocean. The birds generated interesting polarimetric signatures. This paper describes the signatures and speculates bird behavior.

  12. Miniature synthetic-aperture radar system (United States)

    Stockton, Wayne; Stromfors, Richard D.


    Loral Defense Systems-Arizona has developed a high-performance synthetic-aperture radar (SAR) for small aircraft and unmanned aerial vehicle (UAV) reconnaissance applications. This miniature radar, called Miniature Synthetic-Aperture Radar (MSAR), is packaged in a small volume and has low weight. It retains key features of large SAR systems, including high-resolution imaging and all-weather operation. The operating frequency of MSAR can optionally be selected to provide foliage penetration capability. Many imaging radar configurations can be derived using this baseline system. MSAR with a data link provides an attractive UAV sensor. MSAR with a real-time image formation processor is well suited to installations where onboard processing and immediate image analysis are required. The MSAR system provides high-resolution imaging for short-to-medium range reconnaissance applications.

  13. Space-qualifiable Digital Radar Transceiver Project (United States)

    National Aeronautics and Space Administration — Radar technology offers a very flexible, powerful tool for applications such as object detection, tracking, and characterization, as well as remote sensing, imaging,...

  14. Next-Generation Spaceborne Cloud Profiling Radars (United States)

    Tanelli, Simone; Durden, Stephen L.; Im, Eastwood; Heymsfield, Gerald M.; Racette, Paul; Starr, Dave O.


    One of the instruments recommended for deployment on the Aerosol/Cloud/Echosystems (ACE) mission is a new advanced Cloud Profiling Radar (ACE-CPR). The atmospheric sciences community has initiated the effort to define the scientific requirements for this instrument. Initial studies focusing on system configuration, performance and feasibility start from the successful experience of the Cloud Profiling Radar on CloudSat Mission (CS-CPR), the first 94-GHz nadir-looking spaceborne radar which has been acquiring global time series of vertical cloud structure since June 2, 2006. In this paper we address the significance of CloudSat's accomplishments in regards to the design and development of radars for future cloud profiling missions such as EarthCARE and ACE.

  15. Space Compatible Radar Absorbing Materials Project (United States)

    National Aeronautics and Space Administration — This SBIR Phase 1 project shall investigate novel radar absorbing materials (RAM) for use in space or simulated space environments. These materials are lightweight...

  16. Radar Mapping of Surface Soil Moisture (United States)

    Ulaby, F. T.; Dubois, P. C.; van Zyl, J.


    Intended as an overview aimed at potential users of remotely sensed spatial distributions and temporal variations of soil moisture, this paper begins with an introductory section on the fundamentals of radar imaging and associated attributes.

  17. ASTEROID RADAR V6.0 (United States)

    National Aeronautics and Space Administration — This data set is intended to include all groundbased asteroid radar detections. These entries were collected by Steven J. Ostro, and selected data have been provided...

  18. ASTEROID RADAR V12.0 (United States)

    National Aeronautics and Space Administration — This data set is intended to include all published groundbased asteroid radar detections. The entries were collected by Steven J. Ostro, and selected data have been...

  19. ASTEROID RADAR V4.0 (United States)

    National Aeronautics and Space Administration — This data set is intended to include all groundbased asteroid radar detections. These data were collected from the published literature by Steven J. Ostro (1989)...

  20. ASTEROID RADAR V11.0 (United States)

    National Aeronautics and Space Administration — This data set is intended to include all published groundbased asteroid radar detections. The entries were collected by Steven J. Ostro, and selected data have been...

  1. ASTEROID RADAR V3.0 (United States)

    National Aeronautics and Space Administration — This dataset is intended to include all groundbased asteroid radar detections. These data were collected from the published literature by Dr. Steven J. Ostro....

  2. ASTEROID RADAR V5.0 (United States)

    National Aeronautics and Space Administration — This data set is intended to include all groundbased asteroid radar detections. These entries were collected by Steven J. Ostro (1989) [OSTRO1989] and selected data...

  3. ASTEROID RADAR V10.0 (United States)

    National Aeronautics and Space Administration — This data set is intended to include all published groundbased asteroid radar detections. The entries were collected by Steven J. Ostro, and selected data have been...

  4. ASTEROID RADAR V13.0 (United States)

    National Aeronautics and Space Administration — This data set is intended to include all published groundbased asteroid radar detections. The entries were collected by Steven J. Ostro, and selected data have been...

  5. ASTEROID RADAR V9.0 (United States)

    National Aeronautics and Space Administration — This data set is a compilation of all groundbased asteroid radar detections. The collection is maintained and updated by Steven Ostro. It is updated annually.

  6. ASTEROID RADAR V14.0 (United States)

    National Aeronautics and Space Administration — This data set is intended to include all published groundbased asteroid radar detections. The entries were collected by Steven J. Ostro, and selected data have been...

  7. Ground penetrating radar evaluation and implementation. (United States)


    Six commercial ground penetrating radar (GPR) : systems were evaluated to determine the state-of-the-art of GPR technologies for railroad track : substructure inspection. : Phase 1 evaluated GPR ballast inspection : techniques by performing testing a...

  8. GEOGRAPHOS RADAR V1.0 (United States)

    National Aeronautics and Space Administration — Goldstone radar observations of 1620 Geographos from August 28 through Sept. 2, 1994 yield delay-Doppler images whose linear spatial resolutions range from ~75 to...

  9. Greenland Radar Ice Sheet Thickness Measurements (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...

  10. Simulating lightning tests to radar system

    NARCIS (Netherlands)

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


    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.

  11. Three Band Cloud and Precipitation Radar (United States)

    National Aeronautics and Space Administration — We propose to design and demonstrate key enabling technologies for Cloud and Precipitation radars capable of closing the observational gaps left by current and...

  12. Space-Qualifiable Digital Radar Transceiver Project (United States)

    National Aeronautics and Space Administration — Historically, radar systems have tended to be either large, complex, power-hungry, purpose-built systems, or extremely simple systems of limited capability. More...

  13. TCSP CLOUD RADAR SYSTEM (CRS) V1 (United States)

    National Aeronautics and Space Administration — The Cloud Radar System (CRS) provides vertically profiled reflectivity and Doppler velocity at aircraft nadir along the flight track. The CRS is a 94 GHz (W-band; 3...

  14. NAMMA TOGA RADAR DATA V1 (United States)

    National Aeronautics and Space Administration — This dataset consists of a collection of products derived from the NASA TOGA radar observations that were collected in the Republic of Cape Verde during the NAMMA...

  15. Advancing Radar Technologies for Space Exploration (United States)

    National Aeronautics and Space Administration — Remote sensing technologies remain the primary means by which scientific knowledge about the surrounding universe is gathered in lieu of human exploration. Radar...

  16. Integrating Millimeter Wave Radar with a Monocular Vision Sensor for On-Road Obstacle Detection Applications

    Directory of Open Access Journals (Sweden)

    Zheng Ma


    Full Text Available This paper presents a systematic scheme for fusing millimeter wave (MMW radar and a monocular vision sensor for on-road obstacle detection. As a whole, a three-level fusion strategy based on visual attention mechanism and driver’s visual consciousness is provided for MMW radar and monocular vision fusion so as to obtain better comprehensive performance. Then an experimental method for radar-vision point alignment for easy operation with no reflection intensity of radar and special tool requirements is put forward. Furthermore, a region searching approach for potential target detection is derived in order to decrease the image processing time. An adaptive thresholding algorithm based on a new understanding of shadows in the image is adopted for obstacle detection, and edge detection is used to assist in determining the boundary of obstacles. The proposed fusion approach is verified through real experimental examples of on-road vehicle/pedestrian detection. In the end, the experimental results show that the proposed method is simple and feasible.

  17. Energy expenditure and balance during spaceflight on the space shuttle (United States)

    Stein, T. P.; Leskiw, M. J.; Schluter, M. D.; Hoyt, R. W.; Lane, H. W.; Gretebeck, R. E.; LeBlanc, A. D.


    The objectives of this study were as follows: 1) to measure human energy expenditure (EE) during spaceflight on a shuttle mission by using the doubly labeled water (DLW) method; 2) to determine whether the astronauts were in negative energy balance during spaceflight; 3) to use the comparison of change in body fat as measured by the intake DLW EE, 18O dilution, and dual energy X-ray absorptiometry (DEXA) to validate the DLW method for spaceflight; and 4) to compare EE during spaceflight against that found with bed rest. Two experiments were conducted: a flight experiment (n = 4) on the 16-day 1996 life and microgravity sciences shuttle mission and a 6 degrees head-down tilt bed rest study with controlled dietary intake (n = 8). The bed rest study was designed to simulate the flight experiment and included exercise. Two EE determinations were done before flight (bed rest), during flight (bed rest), and after flight (recovery). Energy intake and N balance were monitored for the entire period. Results were that body weight, water, fat, and energy balance were unchanged with bed rest. For the flight experiment, decreases in weight (2.6 +/- 0.4 kg, P balance of 1,355 +/- 80 kcal/day (-15. 7 +/- 1.0 kcal. kg-1. day-1, P body fat, which was within experimental error of the fat loss determined by 18O dilution (-1.4 +/- 0.5 kg) and DEXA (-2.4 +/- 0.4 kg). All three methods showed no change in body fat with bed rest. In conclusion, 1) the DLW method for measuring EE during spaceflight is valid, 2) the astronauts were in severe negative energy balance and oxidized body fat, and 3) in-flight energy (E) requirements can be predicted from the equation: E = 1.40 x resting metabolic rate + exercise.

  18. Solving for ambiguities in radar geophysical exploration of planetary bodies by mimicking bats echolocation. (United States)

    Carrer, Leonardo; Bruzzone, Lorenzo


    Sounders are spaceborne radars which are widely employed for geophysical exploration of celestial bodies around the solar system. They provide unique information regarding the subsurface structure and composition of planets and their moons. The acquired data are often affected by unwanted artifacts, which hinder the data interpretation conducted by geophysicists. Bats possess a remarkable ability in discriminating between a prey, such as a quick-moving insect, and unwanted clutter (e.g., foliage) by effectively employing their bio-sonar perfected in million years of evolution. Striking analogies occur between the characteristics of bats sonar and the one of a radar sounder. Here we propose an adaptation of the unique bat clutter discrimination capability to radar sounding by devising a novel clutter detection model. The proposed bio-inspired strategy proves its effectiveness on Mars experimental data and paves the way for a new generation of sounders which eases the data interpretation by planetary scientists.

  19. Three-dimensional ground penetrating radar imaging using multi-frequency diffraction tomography

    Energy Technology Data Exchange (ETDEWEB)

    Mast, J.E.; Johansson, E.M. [Lawrence Livermore National Lab., CA (United States)


    In this talk we present results from a three-dimensional image reconstruction algorithm for impulse radar operating in monostatic pule-echo mode. The application of interest to us is the nondestructive evaluation of civil structures such as bridge decks. We use a multi-frequency diffraction tomography imaging technique in which coherent backward propagations of the received reflected wavefield form a spatial image of the scattering interfaces within the region of interest. This imaging technique provides high-resolution range and azimuthal visualization of the subsurface region. We incorporate the ability to image in planarly layered conductive media and apply the algorithm to experimental data from an offset radar system in which the radar antenna is not directly coupled to the surface of the region. We present a rendering in three-dimensions of the resulting image data which provides high-detail visualization.

  20. Experimenting level set-based snakes for contour segmentation in radar imagery (United States)

    Lesage, Frederic; Gagnon, Langis


    The aim of this work is to explore the applicability of a relatively new snakes formulation called geometric snakes, for robust contour segmentation in radar images. In particular, we are looking for clear experimental indicators regarding the usefulness of such tool for radar imagery. In this work, we mainly concentrate on various contour segmentation problems in airborne and spaceborne SAR images (swatch and inverse mode). As an example, we study the segmentation of coastlines and ship targets. We observe that the dynamical and adaptive properties of geometric contours is better suited to determine the morphological properties of the contours. For high-resolution radar images of ships, the underlying motivation is that these properties could help providing robust extraction of ship structures for automatic ship classification.