WorldWideScience

Sample records for anti-jamming

  1. Electromagnetic anti-jam telemetry tool

    Science.gov (United States)

    Ganesan, Harini; Mayzenberg, Nataliya

    2008-02-12

    A mud-pulse telemetry tool includes a tool housing, a motor disposed in the tool housing, and a magnetic coupling coupled to the motor and having an inner shaft and an outer shaft. The tool may also include a stator coupled to the tool housing, a restrictor disposed proximate the stator and coupled to the magnetic coupling, so that the restrictor and the stator adapted to generate selected pulses in a drilling fluid when the restrictor is selectively rotated. The tool may also include a first anti-jam magnet coupled to the too housing, and an second anti-jam magnet disposed proximate the first anti-jam magnet and coupled to the inner shaft and/or the outer shaft, wherein at least one of the first anti-jam magnet and the second anti-jam magnet is an electromagnet, and wherein the first anti-jam magnet and the second anti-jam magnet are positioned with adjacent like poles.

  2. Studies on Novel Anti-jamming Technique of Unmanned Aerial Vehicle Data Link

    Institute of Scientific and Technical Information of China (English)

    Huang Wenzhun; Wang Yongsheng; Ye Xiangyang

    2008-01-01

    Based on the M-ary spread spectrum (M-ary-SS), direct sequence spread spectrum (DS-SS), and orthogonal frequency division multiplex (OFDM), a novel anti-jamming scheme, named orthogonal code time division multi-subchannels spread spectrum modulation (OC-TDMSCSSM), is proposed to enhance the anti-jamming ability of the unmanned aerial vehicle (UAV) data link. The anti-jamming system with its mathematical model is presented first, and then the signal formats of transmitter and receiver are derived. The receiver's bit error rate (BER) is demonstrated and anti-jamming performance analysis is carried out in an additive white Ganssian noise (AWGN) channel. Theoretical research and simulation results show the anti-jamming performance of the proposed scheme better than that of the hybrid direct sequence frequency hopping spread spectrum (DS/FH SS) system. The jamming margin of the OC-TDMSCSSM system is 5 dB higher than that of DS/FH SS system under the condition of lUcian channel and full-band jamming, and 6 dB higher under the condition of Rician channel environment and partial-band jamming.

  3. Combined algorithm of acquisition and anti-jamming based on SFT

    Institute of Scientific and Technical Information of China (English)

    Ying Ma; Xiangyuan Bu; Hangcheng Han; Qiaoxian Gong

    2015-01-01

    A communication and navigation receiver is required to remove hostile jamming signals and synchronize receiving signals effectively especial y for satel ite communication and navigation whose resources are becoming more and more limited. This paper proposes a novel signal receiving method by combining the pro-cesses of anti-jamming and synchronization to reduce the overal computational complexity at the expense of slightly affecting the detection probability, which is analyzed in detail by derivations. Furthermore, this paper introduces sparse Fourier transformation (SFT) into the proposed algorithm to replace fast Fourier transfor-mation (FFT) so as to further reduce the calculation time especial y in large frequency offset environments.

  4. Collaborative Anti-jamming in Cognitive Radio Networks Using Minimax-Q Learning

    Directory of Open Access Journals (Sweden)

    Sangeeta Singh

    2013-10-01

    Full Text Available Cognitive radio is an efficient technique for realization of dynamic spectrum access. Since in the cognitive radio network (CRN environment, the secondary users (SUs are susceptible to the random jammers, the security issue of the SU’s channel access becomes crucial for the CRN framework. The rapidly varying spectrum dynamics of CRN along with the jammer’s actions leads to challenging scenario. Stochastic zero-sum game and Markov decision process (MDP are generally used to model the scenario concerned. To learn the channel dynamics and the jammer’s strategy the SUs use reinforcement learning (RL algorithms, like Minimax-Q learning. In this paper, we have proposed the multi-agent multi-band collaborative anti-jamming among the SUs to combat single jammer using the Minimax-Q learning algorithm. The SUs collaborate via sharing the policies or episodes. Here, we have shown that the sharing of the learned policies or episodes enhances the learning probability of SUs about the jammer’s strategies but reward reduces as the cost of communication increases. Simulation results show improvement in learning probability of SU by using collaborative anti-jamming using Minimax-Q learning over single SU fighting the jammer scenario.

  5. GPS抗干扰技术发展趋势%Development Trend of GPS Anti-jamming Technique

    Institute of Scientific and Technical Information of China (English)

    刘海波; 吴德伟; 董成喜; 卢艳娥

    2011-01-01

    随着信息技术的深入发展,研究复杂电磁环境下的GPS干扰和抗干扰,对打赢未来信息化条件下的局部战争,具有十分重要的意义.从GPS工作的基本原理出发,在卫星、地面监控系统、接收系统等方面分析了对GPS的干扰措施,阐明了GPS抗干扰技术的现状,指出了几个未来重点发展方向,并提出了提高北斗导航系统导航保障能力的建议.%With the development of communication technologies, researching on the interference and anti-jamming issues of GPS under complex electromagnetic circumstances has become very important in winning aftertime information-age local warfares.The existing interference and anti-jamming methods aimed at the GPS satellites, ground monitoring and control system and the receiving terminals were analyzed, and the interference and anti-jamming development tendency was forecasted.Suggestions were given in improving the anti-jamming capability of BD Satellite Navigation System.

  6. Space-borne antenna adaptive anti-jamming method based on gradient-genetic algorithm

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A novel space-borne antenna adaptive anti-jamming method based on the genetic algorithm(GA), which is combined with gradient-like reproduction operators is presented,to search for the best weight for pattern synthesis in radio frequency(RF).Combined,the GA's the capability of the whole searching is,but not limited by selection of the initial parameter,with the gradient algorithm's advantage of fast searching.The proposed method requires a smaller sized initial population and lower computational complexity.Therefore,it is flexible to implement this method in the real-time systems.By using the proposed algorithm,the designer can efficiently control both main-lobe shaping and side-lobe level.Simulation results based on the spot survey data show that the algorithm proposed is efficient and feasible.

  7. AntiJam: Efficient Medium Access despite Adaptive and Reactive Jamming

    CERN Document Server

    Richa, Andrea; Schmid, Stefan; Zhang, Jin

    2010-01-01

    Intentional interference constitutes a major threat for communication networks operating over a shared medium and where availability is imperative. Jamming attacks are often simple and cheap to implement. In particular, today's jammers can perform physical carrier sensing in order to disrupt communication more efficiently, specially in a network of simple wireless devices such as sensor nodes, which usually operate over a single frequency (or a limited frequency band) and which cannot benefit from the use of spread spectrum or other more advanced technologies. This paper proposes the medium access (MAC) protocol \\textsc{AntiJam} that is provably robust against a powerful reactive adversary who can jam a $(1-\\epsilon)$-portion of the time steps, where $\\epsilon$ is an arbitrary constant. The adversary uses carrier sensing to make informed decisions on when it is most harmful to disrupt communications; moreover, we allow the adversary to be adaptive and to have complete knowledge of the entire protocol history....

  8. Anti-jamming of Inverse Synthetic Aperture Radar based on Slope-varying Linear Frequency Modulation Signal

    Directory of Open Access Journals (Sweden)

    Zhu Yupeng

    2009-09-01

    Full Text Available Deceptive jamming technology against inverse synthetic aperture radar is matured now, which is meaningful in military application. But the research on anti-jamming technology for inverse synthetic aperture radar (ISAR is still not a mature technology. Through the analysis on the theory of deceptive jamming technology against ISAR, a new method for anti-jamming against ISAR based on linear frequency modulation signal’s frequency slope-varying is presented. The false target echo energy is suppressed due to frequency modulation slope mis-matching. Doppler domain averaging is adopted for improving the quality of the ISAR image, which helps automatic target recognition. Simulation result based on simulating data shows the validity of the new algorithm.Defence Science Journal, 2009, 59(5, pp.537-544, DOI:http://dx.doi.org/10.14429/dsj.59.1556

  9. An SDR-Based Real-Time Testbed for GNSS Adaptive Array Anti-Jamming Algorithms Accelerated by GPU

    Directory of Open Access Journals (Sweden)

    Hailong Xu

    2016-03-01

    Full Text Available Nowadays, software-defined radio (SDR has become a common approach to evaluate new algorithms. However, in the field of Global Navigation Satellite System (GNSS adaptive array anti-jamming, previous work has been limited due to the high computational power demanded by adaptive algorithms, and often lack flexibility and configurability. In this paper, the design and implementation of an SDR-based real-time testbed for GNSS adaptive array anti-jamming accelerated by a Graphics Processing Unit (GPU are documented. This testbed highlights itself as a feature-rich and extendible platform with great flexibility and configurability, as well as high computational performance. Both Space-Time Adaptive Processing (STAP and Space-Frequency Adaptive Processing (SFAP are implemented with a wide range of parameters. Raw data from as many as eight antenna elements can be processed in real-time in either an adaptive nulling or beamforming mode. To fully take advantage of the parallelism resource provided by the GPU, a batched method in programming is proposed. Tests and experiments are conducted to evaluate both the computational and anti-jamming performance. This platform can be used for research and prototyping, as well as a real product in certain applications.

  10. An SDR-Based Real-Time Testbed for GNSS Adaptive Array Anti-Jamming Algorithms Accelerated by GPU.

    Science.gov (United States)

    Xu, Hailong; Cui, Xiaowei; Lu, Mingquan

    2016-03-11

    Nowadays, software-defined radio (SDR) has become a common approach to evaluate new algorithms. However, in the field of Global Navigation Satellite System (GNSS) adaptive array anti-jamming, previous work has been limited due to the high computational power demanded by adaptive algorithms, and often lack flexibility and configurability. In this paper, the design and implementation of an SDR-based real-time testbed for GNSS adaptive array anti-jamming accelerated by a Graphics Processing Unit (GPU) are documented. This testbed highlights itself as a feature-rich and extendible platform with great flexibility and configurability, as well as high computational performance. Both Space-Time Adaptive Processing (STAP) and Space-Frequency Adaptive Processing (SFAP) are implemented with a wide range of parameters. Raw data from as many as eight antenna elements can be processed in real-time in either an adaptive nulling or beamforming mode. To fully take advantage of the parallelism resource provided by the GPU, a batched method in programming is proposed. Tests and experiments are conducted to evaluate both the computational and anti-jamming performance. This platform can be used for research and prototyping, as well as a real product in certain applications.

  11. An SDR-Based Real-Time Testbed for GNSS Adaptive Array Anti-Jamming Algorithms Accelerated by GPU.

    Science.gov (United States)

    Xu, Hailong; Cui, Xiaowei; Lu, Mingquan

    2016-01-01

    Nowadays, software-defined radio (SDR) has become a common approach to evaluate new algorithms. However, in the field of Global Navigation Satellite System (GNSS) adaptive array anti-jamming, previous work has been limited due to the high computational power demanded by adaptive algorithms, and often lack flexibility and configurability. In this paper, the design and implementation of an SDR-based real-time testbed for GNSS adaptive array anti-jamming accelerated by a Graphics Processing Unit (GPU) are documented. This testbed highlights itself as a feature-rich and extendible platform with great flexibility and configurability, as well as high computational performance. Both Space-Time Adaptive Processing (STAP) and Space-Frequency Adaptive Processing (SFAP) are implemented with a wide range of parameters. Raw data from as many as eight antenna elements can be processed in real-time in either an adaptive nulling or beamforming mode. To fully take advantage of the parallelism resource provided by the GPU, a batched method in programming is proposed. Tests and experiments are conducted to evaluate both the computational and anti-jamming performance. This platform can be used for research and prototyping, as well as a real product in certain applications. PMID:26978363

  12. Research on Evaluation of Netted Radar Anti-jamming Capability%雷达网抗干扰能力评估研究

    Institute of Scientific and Technical Information of China (English)

    周武; 董文锋; 许端

    2012-01-01

      为有效地评价雷达网的抗电子干扰能力,在层次分析法评估雷达抗干扰能力的基础上,综合考虑干扰条件下单部雷达的抗干扰能力以及雷达网的附加抗干扰能力,提出了评估雷达网抗干扰能力的表达式;最后给出了实例分析和评估。评估结果验证了该表达式用来度量雷达网抗干扰能力是有效的。%  In order to evaluate effectively the anti-jamming capability of netted radars, on the basis of using AHP to evaluate anti-jamming capability of radar and having an overall consideration of the single radar anti-jamming and the netted radars’additional anti-jamming capabilities, this paper presents an expression of anti-jamming capability of netted radars, and gives its example analysis and evaluation. Evaluation results show that the proposed expression can be effective in measuring the anti-jamming capability of netted radars.

  13. A Real-Time Capable Software-Defined Receiver Using GPU for Adaptive Anti-Jam GPS Sensors

    Directory of Open Access Journals (Sweden)

    Dennis Akos

    2011-09-01

    Full Text Available Due to their weak received signal power, Global Positioning System (GPS signals are vulnerable to radio frequency interference. Adaptive beam and null steering of the gain pattern of a GPS antenna array can significantly increase the resistance of GPS sensors to signal interference and jamming. Since adaptive array processing requires intensive computational power, beamsteering GPS receivers were usually implemented using hardware such as field-programmable gate arrays (FPGAs. However, a software implementation using general-purpose processors is much more desirable because of its flexibility and cost effectiveness. This paper presents a GPS software-defined radio (SDR with adaptive beamsteering capability for anti-jam applications. The GPS SDR design is based on an optimized desktop parallel processing architecture using a quad-core Central Processing Unit (CPU coupled with a new generation Graphics Processing Unit (GPU having massively parallel processors. This GPS SDR demonstrates sufficient computational capability to support a four-element antenna array and future GPS L5 signal processing in real time. After providing the details of our design and optimization schemes for future GPU-based GPS SDR developments, the jamming resistance of our GPS SDR under synthetic wideband jamming is presented. Since the GPS SDR uses commercial-off-the-shelf hardware and processors, it can be easily adopted in civil GPS applications requiring anti-jam capabilities.

  14. A real-time capable software-defined receiver using GPU for adaptive anti-jam GPS sensors.

    Science.gov (United States)

    Seo, Jiwon; Chen, Yu-Hsuan; De Lorenzo, David S; Lo, Sherman; Enge, Per; Akos, Dennis; Lee, Jiyun

    2011-01-01

    Due to their weak received signal power, Global Positioning System (GPS) signals are vulnerable to radio frequency interference. Adaptive beam and null steering of the gain pattern of a GPS antenna array can significantly increase the resistance of GPS sensors to signal interference and jamming. Since adaptive array processing requires intensive computational power, beamsteering GPS receivers were usually implemented using hardware such as field-programmable gate arrays (FPGAs). However, a software implementation using general-purpose processors is much more desirable because of its flexibility and cost effectiveness. This paper presents a GPS software-defined radio (SDR) with adaptive beamsteering capability for anti-jam applications. The GPS SDR design is based on an optimized desktop parallel processing architecture using a quad-core Central Processing Unit (CPU) coupled with a new generation Graphics Processing Unit (GPU) having massively parallel processors. This GPS SDR demonstrates sufficient computational capability to support a four-element antenna array and future GPS L5 signal processing in real time. After providing the details of our design and optimization schemes for future GPU-based GPS SDR developments, the jamming resistance of our GPS SDR under synthetic wideband jamming is presented. Since the GPS SDR uses commercial-off-the-shelf hardware and processors, it can be easily adopted in civil GPS applications requiring anti-jam capabilities.

  15. Anti-jamming Design for Mobile Command System Communication%机动式指挥系统通信抗干扰设计

    Institute of Scientific and Technical Information of China (English)

    孔令涛; 常冬友

    2011-01-01

    为了对抗敌方的各种通信干扰,机动式指挥系统通信传输必须综合应用各种抗干扰措施,提升抗干扰能力。介绍了机动式指挥系统通信传输业务类型以及各类通信手段传榆性能,在此基础上,重点介绍了提高机动式指挥系统通信抗干扰能力的几种方法,并给出了具体实例。%To counter various jamming technologies for the enemy, a mobile command system needs to integrate different kinds of anti-jamming technology to improve its anti-jamming capability. This paper firstly introduces different operation types of mobile command system communication and the performance of each transmission method. Then, several methods for improving the anti-jamming capability of mobile command system communication are introduced and implementation cases are given.

  16. 无人机角跟踪系统抗干扰性能分析%Analysis on Anti-jamming Performance of Angle Tracking System of UAV

    Institute of Scientific and Technical Information of China (English)

    盛怀洁; 廖明飞

    2014-01-01

    The anti-jamming performance of TT&C system of UAV is mostly decided by that of its angle tracking system. In this paper,the classification of angle tracking system of UAV is studied. The qualitative analysis on the interference response of system is done.Four specifications of anti-jamming performance of system are put forward based on classification of interference response.The defi-nitions and the calculation methods of specifications are given,and their physical significance is elaborated. The method of quantitative analysis of anti-jamming performance of system is proposed.%无人机角跟踪系统的抗干扰性能很大程度上决定了无人机测控系统的抗干扰性能。研究了无人机角跟踪系统的体制分类,定性分析了系统对干扰的干扰响应,在干扰响应分类的基础上提出了4个系统抗干扰性能指标,并对各指标进行了定义。给出了指标计算方法,阐明了指标的物理意义,提出了无人机角跟踪系统抗干扰性能定量分析的方法。

  17. 基于FPGA的GNSS接收机抗干扰的设计%Anti-jamming Design of FPGA-based GNSS Receiver

    Institute of Scientific and Technical Information of China (English)

    何訸; 张旭东

    2012-01-01

    Due to the signal of GNSS arriving at the ous kinds of interference. Especially in the war, the surface is so weak that the GNSS receiver is vulnerable to vari- high power interference transmitted by the enemy would impact the GNSS receiver severely, and the GNSS receiver cannot work normally if we do not use any ant-jamming tech- nique. An anti-jamming scheme uniting frequency domain and space domain is proposed. The simulation result demonstrates that anti-jamming algorithm uniting frequency domain and space domain is better than frequency domain and space domain anti-jamming algorithms, and it can be implemented on FPGA by using Verilog language.%由于到达地面的GNSS信号很微弱,导致GNSS接收机极易受到干扰。特别是在作战时,敌方发射的强干扰对GNSS接收机影响很大,如果不施以抗干扰措施,接收机将无法正常工作。本文提出了频域——空域联合抗干扰的技术方案,仿真结果表明频域——空域联合抗干扰的算法比频域抗干扰算法和空域抗干扰算法性能更优越,在FPGA中用Verilog语言实现了该联合域抗干扰的算法。

  18. Capabilities of LEO Enhanced COMPASS Navigation System for Anti-jamming%基于LEO增强的COMPASS导航系统抗干扰能力研究

    Institute of Scientific and Technical Information of China (English)

    邓琳; 李广侠; 田世伟; 刘仁甫

    2012-01-01

    With the development of COMPASS in civilian and military domain, the request of anti-jamming performance is becoming more and more demanding. Adopting LEO communication satellite system to enhance COMPASS positioning and timing performance is an effective way, es- pecially under jamming. In the angle of signal enhanced, the anti-jamming performance of en- hanced signal broadcasted by LEO satellites was researched. Firstly, the system model and the work principle of LEO enhanced system was introduced. Secondly, the effects of the interfering link were analyzed. Then via the calculations of the enhanced signals from LEO satellites, the an- ti-jamming performance of the enhanced signal was analyzed. Finally, some measures were pro- posed to improve the anti-jamming performance of the enhanced signal. The results show that the enhanced signal can tolerate about 50 dB jamming to signal ratio, and the ability of anti-jamming is equal to GPS M-code.%随着COMPASS系统在民用、军事等应用领域的不断扩展和深入,用户对接收机抗干扰性能要求也会越来越高。在干扰条件下,采用低轨道(LEO)通信卫星对COMPASS系统进行增强是一种比较有效的星基增强方法。文章从信号增强的角度出发,以LEO卫星所播发的导航增强信号为依据,研究LEO增强信号所能容忍的压制干扰的干信比作为衡量增强信号的抗干扰能力指标。首先介绍基于LEO通信卫星增强的COMPASS系统组成及工作原理;其次分析干扰链路的影响;然后通过计算,对LEO卫星播发的增强信号能量及抗干扰性能进行分析;最后,提出一些措施改善增强信号的抗干扰能力。结果表明,经改善后的LEO通信卫星播发的导航增强信号可容忍50dB左右的干信比,与GPS中M码信号的抗干扰能力相当。

  19. Research on Anti-jamming RF-EAS System%射频EAS系统的抗干扰研究

    Institute of Scientific and Technical Information of China (English)

    李威; 邓计才

    2014-01-01

    At present, the market of RF-EAS systems is still very large, accompanied by an increasingly serious electromagnetic interference the anti-jamming performance of it also faces greater challenges. This thesis takes AIO (All-In-One) type of RF-EAS systems as the object to study how to improve its anti-interference performance. Interference noise in the article is divided into two types, which are steady noise and transient noise. According to the characteristics of different interference noises, their impacts on all aspects of the system are fully analyzed, and then, we propose a series of targeted hardware and software measures. Finally, the self-adaptability of the system is studied, and we present a feasible way to improve the anti-interference ability and stability of the system.%目前,射频EAS系统的市场应用仍十分广泛,伴随着日益严重的电磁干扰,其抗干扰性能面临着更大的挑战。此文针对一体式射频EAS系统如何提高其抗干扰性能进行研究。根据不同干扰噪声的特点,对稳态干扰和瞬时干扰在系统工作的各个环节上的影响进行分析,有针对性地给出了一系列包括硬件和软件等方面的方法,提出了一种以信噪比为基础提高系统自适应能力的算法,并结合实验仿真进行了验证,结果表明,本方法提升了系统的抗干扰能力和稳定性。

  20. Study of Simulation Algorithm of Adaptive Nulling Antenna Aray for Anti-Jamming in Satellite Positioning Systems%自适应调零天线卫星定位抗干扰算法仿真研究

    Institute of Scientific and Technical Information of China (English)

    初明阳

    2014-01-01

    自适应阵列天线是国内外GPS抗干扰研究的主要方向,自适应调零抗干扰算法是成功应用的抗干扰技术之一。介绍了自适应调零抗干扰的原理,建立了天线阵列的数学模型,基于LMS算法介绍了4个天线单元的自适应调零算法的原理和实现过程,并对算法进行了仿真。结果显示该算法对单干扰、双干扰及三干扰均有较强的抗干扰能力。%Adaptive antenna array is the main research direction of GPS anti j-amming home and a -board, and adaptive nulling anti -jamming algorithm is one of the anti-jamming technologies which uses in practice successfully .This paper introduces the adaptive nulling anti-jamming theory and builds the math-ematical model of the antenna array .And based on LMS , the adaptive nulling algorithm for four antenna elements and its implementation are discussed as well .The algorithm is simulated and its results show that it features relatively strong anti-jamming capability to the mono-tone , dual-tone and triple-tone interfer-ence.

  1. V波段引信反侦察抗干扰性能研究%Anti-reconnaissance and Anti-jamming Performance Research of V-band Fuze

    Institute of Scientific and Technical Information of China (English)

    王虹; 李兴国

    2011-01-01

    Based on the attenuation characteristic of non-atmospheric window V-band, by calculating the reconnaissance aircraft received power of the V-band fuze from different rang, the ant-reconnaissance performance of V band fuze is analyzed ; By simulating the jamming-signal-ratio of the fuze from different range and power active interference based on the relationship between jamming-signal-ratio and effective jamming boundary, o the window band is compared and the jamming effect of the fuze is analyzed. At last by subscale experiment the anti-jamming performance of V-band fuzes verified. The simulation and experiment result indicate that the V-band MMW fuze has better performance in concealment and anti-jamming, although its ranging scale is limited .%根据非大气窗口V波段大气衰减特性,通过仿真计算侦察机接收到的来自不同距离V波段引信的探测信号,分析V波段引信反侦察性能;仿真来自不同距离和功率有源干扰对于V波段引信的干信比值,并根据干信比值与有效干扰界之间的关系,对比窗口频段分析对引信实施干扰的效果.最后通过缩比试验验证V波段引信的抗干扰能力.通过仿真和实验,结果表明V波段毫米波引信虽探测距离受限,但隐蔽性好,抗有源干扰能力强.

  2. Raptor码在卫星通信中抗干扰性能研究%Anti-jamming Performance in Satellite Communications Based on Raptor Codes

    Institute of Scientific and Technical Information of China (English)

    刘琴涛; 刘宏波; 马俊凯

    2013-01-01

    In order to improve the anti-jamming performance of satellite communications,the Raptor codes program of erasure codes used in satellite communications systems is proposed,based on satellite communications channel characteristics analysis.In this paper,the LDPC code and LT code serial concatenated coding is used to achieve a bit rate of 0.95 Raptor code,and the decoding algorithm of Raptor code is studied in the carrier noise interference channel,via system simulation,the satellite communication system model of the Raptor codes was set up based on optimization distribution,and analyze and study the performance of anti-jamming.%为了提高卫星通信抗干扰性能,在对卫星通信的信道特性分析基础上,提出一种将Raptor码作为纠删码应用于卫星通信系统的方案.文中采用了LDPC码+LT码串行级联编码来实现一个码率为0.95的Raptor码,并对在载波噪声干扰信道中传输的Raptor码的译码算法进行了研究,通过系统仿真,搭建一种基于最优化度分布Raptor码的卫星通信系统模型,并对其抗干扰的性能进行分析及研究.

  3. 星间链路抗干扰性能分析%Anti-jamming Performance Analysis of Inter-satellite Link

    Institute of Scientific and Technical Information of China (English)

    谢学东; 颜树华; 陈建云

    2011-01-01

    星间链路中干扰是影响链路测量准确度的重要因素.抗干扰性能分析可以通过链路卫星空间状态信息和通信规划,分析不同类型的干扰对链路的干扰概率和干扰强度,最终得出链路对不同类型干扰的抗干扰能力.基于星间链路模型,结合链路通信规划,选择对链路系统影响较大的互干扰和单频干扰,分析了系统在运行周期内的干扰特性.经验证得出该链路模型和通信规划受互干扰影响较小,地面强干扰对系统影响可能导致单颗卫星短暂无法正常工作,但不会对整个星座性能产生影响.%Jamming within inter-satellite link is the important factor influencing the measuring accuracy of the link system. According to the state space information of link satellites and communications planning, anti-jamming performance analysis figures out the interference probability and the interference intensity, and eventually, anti-jamming ability of the link to various types of disturbances is demonstrated. The analysis is based on the model of the inter-satellite link. Through combining the link communications planning technique and selecting mutual interferences and signal-tone interferences that have a greater impact on the link system, interference characteristics within the system operational cycle are analyzed It is validated that the link model and communications planning are less affected by the mutual interference, and strong interferences from the ground could lead a single satellite of the system to stop normally working in a short time, but will not affect the performance of the entire constellation.

  4. Overview of research on key techniques for anti-jamming of UAV data link%UAV数据链抗干扰的关键技术研究综述

    Institute of Scientific and Technical Information of China (English)

    李思佳; 毛玉泉; 郑秋容; 李波

    2011-01-01

    无人机(unmanned aerial vehicle,UAV)数据链抗干扰功能的增强是UAV实现战时信息资源共享的核心目标.在分析现有无人机数据链研究现状的基础上,重点综述了UAV数据链抗干扰功能的两类方案:一是在单链路方面,对现有UAV数据链的信道编/解码技术作了比较,并对其他抗干扰现状进行了研究;二是多链路方面,对多链路组网的抗干扰技术进行了深入分析,综述了协同通信在多链路UAV数据链中的应用.抗干扰关键技术的综述为下一代UAV数据链的研发提供一定的理论与技术基础.%The key goal of sharing martial information resources is to enhance the anti-jamming function of UAV data link.Based on analyzing actuality of UAV data link, overviewed two issues for anti-jamming of UAV data link.Firstly, made a comparison of methods for channel code of current UAV data link and performed an overview of researches on anti-jamming techniques.Secondly, analyzed a review of anti-jamming techniques using in multi-link network.Lastly, presented an overview of application research on cooperative communication in the multi-link network of the UAV data link.Provided some kinds of foundation for next generation UAV data link through the overview of research on theoretic and techniques.

  5. 某型雷达宽-限-窄电路噪声调频抗干扰措施研究%Research into Frequency Modulated Noise Anti-jamming Measure Based on WBDF Circuit for Certain Radar

    Institute of Scientific and Technical Information of China (English)

    袁佳杰; 谢乘峰

    2012-01-01

    This paper quantitatively analyzes the operational performance of pulse Doppler (PD) radar adopting the anti-jamming countermeasure based on wideband dicke-fix (WBDF) circuit in the frequency modulated noise jamming environment, compares with the operational performance of the radar without any anti-jamming measures, obtains the factors effeeting on the radar operational performance in the jamming environment,validates the validity of this anti-jamming measure.%定量分析了脉冲多普勒(PD)雷达采用宽-限-窄电路抗干扰措施后在调频噪声干扰环境中的工作性能,与该雷达未采用抗干扰措施时的工作性能进行了对比,得到了干扰环境中影响雷达工作性能的因素,验证了该抗干扰措施的有效性。

  6. 改进SDM算法在CAN总线通信卡抗干扰设计中的应用%SDM Algorithm in the Application of the Communication Card Anti-jamming Design

    Institute of Scientific and Technical Information of China (English)

    顾名宇

    2014-01-01

    提出了一种基于改进SDM通信卡抗干扰算法,分析了经典SDM算法,该种算法在有噪情况以及严重噪声干扰系统的情况下,信号分离质量大大降低,无法准确恢复有价值信号,改进后的SDM算法采用双态信道模型获取通信卡的平均误码率,实现对通信卡干扰情况下信号传递的控制,是一种有效的抗干扰算法。仿真实验结果说明,改进SDM方法下通信卡的抗干扰性远远高于经典SDM方法,是一种稳健的通信卡抗干扰方法。%This paper proposes a algorithm based on improved SDM communication card anti-interference, analyzed the classical algorithm of SDM, this kind of algorithm for noise and serious noise of signal separation quality is greatly re-duced, unable to recover valuable signal accurately, improve SDM algorithm USES binary channel model for the average ber communication card, realize the communication card interference signals under control, is a kind of effective anti-jamming algorithm. Simulation experiment results show that, to improve the anti-jamming of communication card under the SDM method is higher than classical SDM method, anti-jamming method is a robust communication card.

  7. 利用惯导信息的反舰末制导雷达抗干扰方法%The Anti-jamming Approach of the Anti-ship Terminal Radar Aided by INS Information

    Institute of Scientific and Technical Information of China (English)

    来庆福; 刘义; 赵晶; 冯德军; 王雪松

    2011-01-01

    Featured characteristic of ineitial navigation system (INS) information, as short-term accuracy, ultra stability and self-determination, cannot be disturbed by electromagnetic interference. In light of these traits, a novel information processing approach aided by INS position and velocity information for anti-jamming application was proposed,. Based on missile-to-target relative motion model, during the terminal guidance tracking phase of anti-ship missile (ASM), target position and velocity information could be obtained by extended Kalman filtering to suppress seeker random measurement errors. When the jamming was detected, one can combine target position forecast with INS navigation solution to accomplish the homing guidance of ASM, which could help achieve one's purpose of anti-jamming. Simulation was carried out in the presence of a maneuvering ship target, and it shows that this method is effective and feasible because of its preferable anti-jamming performance.%惯导信息短期精度高、稳定性好,且自主工作,不受外界电磁干扰.基于惯导的这些特点,提出了一种利用惯导位置、速度信息辅助抗舷外干扰的信息处理方法:在反舰导弹末制导跟踪阶段,建立弹目相对运动模型,通过扩展卡尔曼滤波降低雷达导引头随机测量误差,获取目标位置和速度信息,当检测到干扰,通过对目标位置的预测和惯导对导弹位置的确定,实现对导弹的制导,以达到抗干扰的目的.在考虑舰船目标机动情况下进行了仿真实验,仿真结果表明了该抗干扰方法是有效和可行的.

  8. Zero bias anti-jamming filter design in non-ideal channel%非理想信道下测量零值无偏干扰抑制滤波器设计

    Institute of Scientific and Technical Information of China (English)

    范广腾; 倪少杰; 唐小妹; 陈华明; 孙广富

    2016-01-01

    There is non-zero bias for the receiver due to the anti-jamming filter in non-ideal channel.Furthermore,since the tap weights of the adaptive transversal filter varies based on jamming pattern,the bias will also vary.This problem of code tracking bias has been a significant hurdle to achieving interference suppression capabilities in precision global navigation satellite system applications.Aiming at this problem,using the symmetrical characteristic of non-ideal analog receiver channel,a new technique called zero bias anti-jamming filter was presented.The proposed method could be easy implement in engineering.Theoretical analysis and simulative results show that the proposed method is capable of reducing the bias to less than 0.2 ns,which is significantly smaller than the traditional adaptive anti-jamming filter.%现有的抗干扰滤波器在通道非理想特性下会导致接收机测量零值发生偏移,且偏移量与干扰参数相关,其已成为高精度测距接收机实现其精度提升的主要障碍。针对上述问题,从对称通道特性出发,给出一种无偏的时域抗干扰滤波器设计技术。解决了传统的时域抗干扰滤波器在非理想信道下测量零值偏移的问题,且工程实现简单。理论分析和仿真实验进一步验证了方法的有效性,采用该方法可以使测量零值偏移小于0.2 ns。

  9. 信息化条件下短波通信抗干扰技术与应用%Technology and Application Research of HF Communication Anti-jamming under the Informatization Condition

    Institute of Scientific and Technical Information of China (English)

    王磊; 李鹤; 周音; 郝强

    2012-01-01

    HF communication is one of the most important means of communication to protect the operational command information un- der the informatization condition, to improve its anti~amming capability is the essential part to ensure the smooth flow of battle command information. This paper analyzes the characteristics of HF communication and the importance of antiamming in HF communications, taking the spread spectrum communication system for example, explains the basic theory of communication anti-jamming, analysis of the various types of interference in HF communication and the corresponding anti-jamming technology, and lists the domestic and foreign technology and equipment which have been developed. Finally, with the requirements of future information warfare and the needs of communication in war- time, the trends of the future HF communication anti-jamming technology are introduced.%短波通信是信息化条件下保障作战指挥的重要通信手段,提高其抗干扰能力是保证作战指挥信息系统稳定的必要环节。文章首先分析了短波通信的特点和短波通信抗干扰的重要性;以扩谱通信抗干扰体制为例阐述了通信抗干扰的基本理论;分析了短波通信中的各类干扰,并针对这些干扰指出了各种抗干扰技术手段,同时列举了国内外已研发的相关技术装备;最后,结合未来信息化战争的要求和战时的通信需求,阐述了未来短波通信抗干扰技术的发展趋势。

  10. 基于调频率捷变的抗移频干扰 SAR 成像方法%SAR Imaging Method of Shift-Frequency Anti-Jamming Based on Chirp Rate Agility

    Institute of Scientific and Technical Information of China (English)

    蒋思源; 吕幼新

    2015-01-01

    针对固定移频 SAR 干扰,提出一种基于调频率极性捷变的抗干扰处理方法,通过改变发射信号中的调频率,改变信号波形,使干扰机很难使用先前侦获的雷达信号参数来干扰雷达工作。理论分析表明,该方法可以有效抑制固定移频干扰对合成孔径雷达带来的影响。在高干信比的情况下,还可以采用调频率极性捷变与限幅相结合的方法来提高抗干扰性能,该方法在处理流程上仅对距离脉冲压缩进行改变,在成像算法中需要对二维频域使用调频率极性捷变与幅度限制相结合的方法。仿真结果表明,事先在雷达发射信号中改变发射信号的调频率,通过改变信号波形进行抗干扰是能达到抗干扰目的的。%Aiming at fixed-shift-frequency SAR jamming,an anti-jamming processing method based on chirp rate polarity agility has been proposed.Through changing the chirp rate of transmit signal to change signal waveform,the difficulty is increased for jammer using the previous radar signal parameters to interfere the radar.Theoretical analysis shows that the method can restrain the influence of fixed-shift-frequency jamming on synthetic aperture radar effectively.In high jamming-to-signal ratio circumstance,using the method of chirp rate polarity agility and combing with amplitude limitation can improve anti-jamming performance.The meth-od only makes change in range pulse compression and uses an imaging algorithm combing chirp rate polarity agility and amplitude limitation in two-dimensional frequency domain.Simulation result shows that through changing chirp rate of transmit signal to change waveform in advance can achieve the target of anti-jamming.

  11. Research on Improving the Anti-jamming Ability of Satellite Signal Using Pseudolites%利用伪卫星提高卫星信号抗干扰能力研究

    Institute of Scientific and Technical Information of China (English)

    吴强; 周坤芳

    2011-01-01

    Aiming at the problem of satellite signal which is easy to be jammed due to the faintness signal power, the interference-to-signal ratio finitude of unlocked GPS receivers is used as judgement standard and the feasibility of improving the anti-jamming ability of satellite signal using pseudolites to enhance signal power is validated.%针对卫星信号功率微弱易受干扰的问题,以GPS接收机失锁时的干信比门限作为接收机是否被干扰而失锁的判别标准,研究伪卫星增强信号功率提高接收机接收卫星信号抗干扰能问题。

  12. A Testing Method for Anti-Jamming Performance of Navigation Terminal Receiver%基于信号模拟器的接收机抗干扰测试方法研究

    Institute of Scientific and Technical Information of China (English)

    郝燕玲; 梁宏; 周广涛

    2014-01-01

    为了衡量导航终端接收机的抗干扰性能,满足产品测试需求,针对干扰信号的复杂特点,研究了导航终端接收机的抗干扰性能测试方法。针对几种典型的干扰信号进行分析和仿真,得到最佳干扰效果。同时利用软件的信号模拟发生器,改变干扰类型、干扰强度以及干扰频段,对卫星导航软件接收机的抗干扰能力进行了测试,仿真实验验证了测试方法的可行性。%To determine the performance of the terminal receiver ,meet the demand for product testing ,aiming at the complex characteristics of interference signal ,an anti-jamming performance test method of the navigation terminal receiver is proved .According to the anal-ysis and simulation of several typical interference signal ,get the optimal jamming effect .At the same time simulation generator using the software signal ,change the interference type , interference intensity and interference frequency band ,the satellite navigation software re-ceiver anti-jamming capability were tested ,the simulation results verify the feasibility of the test method .

  13. Anti -jamming design for diven control power of Stirling cryocooler%分置式斯特林制冷机驱动控制源的抗干扰设计

    Institute of Scientific and Technical Information of China (English)

    杨玉玲; 胥春茜

    2011-01-01

    Jamming from electromagnetism is an important factor to effect the cabability of Stifling cryocooler. This paper presented the anti -jamming design for driven and control power of Stirling cryocooler through hardware and software. In hardware we installed LC filter in the output of driven and control power. The monopole control of electromotor replaced the ambipolar control of electromotor and we installed partition of photoelectricity in the part of testing the temperature etc. In software we used the way of digital filtering for the sampled signal.%电磁干扰问题一直是影响斯特林制冷机性能的重要因素,文中分别从硬件和软件两方面对斯特林制冷机驱动控制源的抗干扰设计作介绍.本设计的硬件方面主要采用驱动控制器的输出部分加装LC滤波器、电机的单极性驱动代替传统的双极性驱动和测温部分装光电隔离器等措施;软件部分主要是对采样到的信号进行数字滤波.

  14. 基于认知无线电的通信抗干扰应用研究%Research on the Application of Anti-jamming based on Cognitive Radio

    Institute of Scientific and Technical Information of China (English)

    余鹏

    2015-01-01

    Cognitive Radio technology are put forward to provide a kind of effective way for solving the contradiction between wireless spectrum resources increasingly tense and of the growing demand for wireless communications applications. The basic concept and the key technology of cognitive radio are introduced, focuses on the analysis of cognitive radio in communication anti jamming strategy is applied and its advantages, to promote the rapid development of communication countermeasure equipment has positive significance.%认知无线电(Cognitive Radio,CR)技术的提出,为解决不断增长的无线通信应用需求与日益紧张的无线频谱资源之间的矛盾提供了一种有效的解决途径。介绍了认知无线电的基本概念和关键技术,重点分析了认知无线电在通信抗干扰中的应用策略及其优势,对促进通信对抗装备的快速发展具有积极意义。

  15. Design and simulation of anti-jamming compatible satellite navigation receiver%抗干扰兼容型卫星导航接收机设计与仿真

    Institute of Scientific and Technical Information of China (English)

    闫杰; 魏培智; 谷建荣; 赵瑞峰

    2013-01-01

    抗干扰兼容型卫星导航接收机既可以使用组合卫星定位系统进行高精度定位,又具有优良的抗干扰性能.其抗干扰性能通过自适应调零天线实现,介绍了系统硬件电路实现,并在相应硬件平台上,采用功率反演算法进行干扰抑制.仿真测试结果表明,自适应调零天线有效地提高了接收信号的信噪比,提高了兼容型卫星导航接收机的应用范围.%Anti-jamming compatible type satellite navigation receiver can use the combination of satellite positioning systems to perform high-precision positioning, and also has an excellent anti-interference performance by the application of adaptive null steering antenna. The hardware circuit of the system is introduced, and the hardware platform is adopted by the power inversion algorithm for interference suppression. Simulation results show that the adaptive null steering antenna can effectively improve the SNR of the received signal, and can expand the application range of compatible type satellite navigation receiver.

  16. 联合空时滤波算法在接收机抗干扰中的应用%Application of Method Based on Space Time Adaptive Filtering Algorithm to Anti-Jamming Receiver

    Institute of Scientific and Technical Information of China (English)

    乐四海; 杨睿峰; 李保东

    2013-01-01

      从空时自适应滤波技术出发,结合数字多波束天线实际应用,提出了一种改进的联合空时滤波算法,解决了当干扰信号与卫星信号空间角接近时,传统的空时滤波算法在抑制干扰信号的同时,极大衰减该卫星有用信号,从而降低了接收机抗干扰性能的问题。仿真和实测结果表明,在卫星信号与干扰信号夹角接近10o和多干扰信号存在的条件下,改进的联合空时滤波算法明显优于传统的空时滤波算法。%Based on the space time adaptive processing technology and in combination with the practical application of digital multi-beam faggot antenna, an improved space time adaptive processing algorithm is put forward. The method is used to solve the problem—that is—traditional space time filtering algorithm can suppress jamming signals, but, at the same time, it can lead to attenuate the signals available of the satellite when the angle between jamming signal and satellite signal is close enough, so that this affects the anti-jamming capability of receiver. The simulation and actual results show the improved space time adaptive processing algorithm is better than the traditional method while the angle between satellite signal and jamming signal is close to 10 degrees and there exists jamming signals.

  17. 低压电力线载波通信与抗干扰解决途径%Solutions for low-voltage power line carrier communication and anti-jamming

    Institute of Scientific and Technical Information of China (English)

    赵新正; 姚发久; 白崇乾; 王阳

    2014-01-01

    Since the power grid is the largest,most popular and reliable network,data transmission through low-voltage power line is the most economical way to use the existing resource. The technology for low-voltage power line multi-frequency self-adaption DSSS carrier communication was created by Shaanxi Kaistar Company,in which the development of IC chip and thick film circuit were included. The jamming from low-voltage power line was completely solved on the basis of the data concentrator, data acquisition unit,data controller and anti-jamming products. The application of power line carrier communication in the energy resources measurement and monitoring platform is superior to the other technologies.%电网是最大、最普及、最可靠的供电网,利用低压电力线实现数据传输,具有利用现有资源、减少投资的现实意义。陕西凯星公司独创了低压电力线多频段自适应直接序列展频载波通信技术,从IC芯片、厚膜电路的研发,从电力线载波数据集中器、采集器、控制器及抗干扰硬件产品入手,彻底解决了低压电力线上的干扰问题。该技术应用在能源计量监控平台方面,是其他技术无法比拟的。

  18. Anti-Jamming with Adaptive Arrays Utilizing Power Inversion Algorithm

    Institute of Scientific and Technical Information of China (English)

    MENG Dawei; FENG Zhenming; LU Mingquan

    2008-01-01

    The convergence rate of the power inversion (PI) algorithm is quite sensitive to the power of the interference with the used fixed parameters in the PI algorithm leading to degradation of its ability to handle interference. This paper presents a normalized PI algorithm that traces the stochastic characteristics of the interference. The algorithm adaptively adjusts the recursive step size to determine the constrained optimized parameters for the Iowpass filter. Simulations show that the normalized PI algorithm achieves faster con-vergence and produces deeper nulls. The algorithm makes GPS receivers more robust in environments with large variations in the interference strength.

  19. Anti-jamming in a fungal transport network

    CERN Document Server

    Hickey, Patrick C; Foshe, Sierra; Roper, Marcus

    2016-01-01

    Congestion limits the efficiency of transport networks ranging from highways to the internet. Fungal hyphal networks are studied as an examples of optimal biological transport networks, but the scheduling and direction of traffic to avoid congestion has not been examined. We show here that the Neurospora crassa fungal network exhibits anticongestion: more densely packed nuclei flow faster along hyphal highways, and transported nuclei self-organize into fast flowing solitons. Concentrated transport by solitons may allow cells to cycle between growing and acting as transport conduits.

  20. GPS Jamming: Strengthening Anti Jam GPS System with Adaptive Phase Only Nulling Using Cuckoo Search

    Directory of Open Access Journals (Sweden)

    V. Thyagarajan

    2014-08-01

    Full Text Available Global Positioning System (GPS signals are spread spectrum, modulated with very low average power caused by background noise. Signal received is mostly 165 dB down than thermal noise level. Such signals are easily jammed either through intentional noise sources (jammer or unintentionally from broadcasting stations harmonics or other out of band sources. This study proposes to reveal how a nulling antenna with adaptive spatial filtering technique can efficiently mitigate intentional and non-intentional interference. A beam forming antenna array is an antennas set whose outputs are weighted by complex values and combined form array output. The complex valued weights effect is to steer the array pattern’s main lobes to desired directions which may be unknown and hence antenna weights are adjusted adaptively till some array performance measure is improved, revealing proper lobe or null placement. This study proposes a Cuckoo Search (CS algorithm based new optimization method for multiple interference cancellation design that increases gain to desired signal and improves jamming rejection performance.

  1. Novel microstrip antenna array for anti-jam satellite navigation system

    OpenAIRE

    Martynyuk, Sergiy Ye.; Vasylenko, Dmytro O.; Dubrovka, Fedor F.; Laush, Anatolii G.

    2015-01-01

    We present results of theoretical and experimental investigations of a novel dual band right hand circularly polarized microstrip antenna array with adaptive space-time processing capability for terminal of GPS/GLONASS/GALILEO satellite navigation systems. The array structure is composed from 10 microstrip radiators excited independently via separate coaxial input ports. Two central radiating elements for two frequency bands (L1 and L2) have got circular shapes with slits and are stacked to p...

  2. GPS抗干扰方法综述%REVIEW ON GPS ANTI-JAM METHOD

    Institute of Scientific and Technical Information of China (English)

    胡永生

    2001-01-01

    全球定位系统提供的低能级信号易受干扰.这些干扰或对抗导致GPS丢失信息,因而成为威胁GPS的严重问题.本文探讨对抗或干扰对GPS的威胁,从策略、干扰源和GPS接收机角度谈抗干扰方法,侧重分析减少GPS干扰的技术.

  3. 电路和分组交换的抗干扰能力分析%Anti-jamming Capability Analysis of Circuit-switch & Packet-switch

    Institute of Scientific and Technical Information of China (English)

    骆连合; 曹彦军; 冯晓东

    2008-01-01

    随着军事信息在现代战争中作用的不断提高,以扰乱或破坏信息传送为目的的通信干扰的作用和地位也随之不断提高.通过对电路交换网络和分组交换网络在被干扰的情况下在物理层、链路层、信令和协议,以及通信业务的影响进行了分析和对比,得出在强干扰模式下网络保障性能大体一致,但是在某些条件下反应的特性分组网络略强.最后指出通信系统本身技术体制的选取是其抗干扰能力好坏的一个重要因素.

  4. 罗兰C信号外场抗干扰能力研究%Study on Anti Jamming Capability of Loran C Signal Field

    Institute of Scientific and Technical Information of China (English)

    赵学军; 窦建龙; 彭怀云

    2015-01-01

    In this paper, by means of Loran C system anti band continuous wave interference ability, strong anti interference ability and the world wave frequency interference ability in the field test experiment, anti-interference ability of Loran C signal is analyzed in typical interference conditions.%本文通过对罗兰C系统抗带外连续波干扰能力、抗强工频干扰能力和天地波交叉干扰能力外场测试实验,分析研究罗兰C信号在典型干扰条件下的外场抗干扰能力。

  5. Research on the Anti-jamming Capabilities for Shortwave of Frequency Hopping Radion%短波跳频电台抗干扰性能

    Institute of Scientific and Technical Information of China (English)

    李国建; 张海勇

    2004-01-01

    短波跳频电台在军事通信中占有重要的地位,它能够确保通信的抗干扰性和隐蔽性.为正确利用短波跳频电台必须对短波跳频电台的抗干扰性能进行研究,分析了短波跳频电台的特点,研究了其抗干扰性能.得出了短波跳频电台的抗干扰性能与跳频电台的跳速、跳频带宽、跳频点数之间的关系,对正确应用短波跳频电台和提高其战斗效能具有重要意义.

  6. A Preliminary Study on CSAMT Anti-jamming Transmitter System%CSAMT发射系统抗干扰供电技术初步研究

    Institute of Scientific and Technical Information of China (English)

    李荡; 王珺璐; 李勇; 李建华; 林品荣

    2016-01-01

    在伪随机编码信号的相关辨识理论基础上,根据可控源音频大地电磁法(CSAM T )测量频率范围及受环境电磁干扰影响的程度,将 CSAM T 测量划分为三个频段,对易受工频及其谐波成分干扰的频段采用伪随机编码发射,高频和低频段采用单频方波发射。发射系统的人机交互和供电波形的产生基于虚拟仪器 LabVIEW(Laboratory Virtual Instrumentation Engineer‐ing Workbench ,实验室虚拟仪器工程平台)软件平台,操作方便、控制灵活。%On the basis of the relevant identification theory of pseudo‐random code signal ,the signals of CSAM T ( Con‐trolled Source Audio‐Frequency Magneto Tellurics) are divided into three parts according frequency range and the extent affect ‐ed by environmental electromagnetic interference .The signals are susceptible to 50Hz interference signal and its harmonic com‐ponents should be set by pseudo‐random code way .Others are set by single square waveform way .The human‐computer inter‐action and waveform generated software of the transmitter system is built on the advanced virtual instrument platform ,Lab‐VIEW (Laboratory Virtual Instrumentation Engineering Workbench ) .The software is easy to operation and flexible to control .

  7. 基于二进制人工蜂群算法的通信抗干扰决策方法%Anti-Jamming Communication Decision Method based on Binary Artificial Bee Colony Algorithm

    Institute of Scientific and Technical Information of China (English)

    惠显杨; 陈建忠; 牛英滔; 齐扬阳

    2016-01-01

    为实现通信抗干扰决策引擎自主调整系统参数的功能,借鉴了一种群体智能优化算法——二进制人工蜂群(binary artificial bee colony,BABC)算法,提出了基于二进制人工蜂群算法的通信抗干扰决策方法.该算法通过模拟蜜蜂采蜜的行为在搜索域中进行寻优,来实现对通信参数的自主选择.针对现有决策算法的不足,该算法对抗干扰决策过程中的目标函数进行合理的设置,使其更加符合实际的通信场景.仿真表明,该算法能够实现通信参数的最优选择,同时能够较好的防止局部最优;与已有的基本遗传算法(genetic algorithm,GA)和粒子群算法(particle swarm optimization,PSO)相比,该算法具有较好的收敛性能.

  8. Research on jamming and anti-jamming technologies in military wireless communication%军用无线通信干扰与抗干扰技术研究

    Institute of Scientific and Technical Information of China (English)

    梁涛

    2015-01-01

    Since wireless communication is the main information transmission method in war,its viability in complex elec⁃tromagnetic environment decides the ability of reliable information transmission directly. To capture information superiority in war and improve system fighting capability based on information system,jamming and anti⁃jamming technologies become the re⁃search emphasis of all military powers in the world. In this paper,the conception,principle and characteristics of jamming methods in military wireless communication are introduced,and also the main anti⁃jamming technologies are presented. The current anti⁃jamming technologies in military wireless communication are analyzed with the example of Link⁃16 tactical data link.%无线通信是战时的主要信息传输手段,其在复杂电磁环境下的生存能力直接决定了交战双方的信息可靠传送能力。因此,为了夺取战时的信息优势,提高基于信息系统的体系作战能力,干扰技术和抗干扰技术成为了世界各军事强国通信技术的研究重点。首先介绍军用无线通信主要干扰手段的概念、原理、特点等,其次介绍针对目前干扰手段的主要抗干扰技术,最后以Link⁃16战术数据链为例,对目前军用无线通信抗干扰技术进行了分析。

  9. A Study of Medium-sized Group of Soccer Robots Anti-jamming System%中型组足球机器人抗干扰系统的研究

    Institute of Scientific and Technical Information of China (English)

    钱晟; 毛丽民; 张亚飞; 浦宇欢

    2012-01-01

      提出了结合RGB和HSI色彩空间的颜色算法以减少光照干扰,基于HSI颜色模型对图像进行二值处理消除噪声;根据实际现场环境,选取最佳方案消除场周围的颜色干扰。实际运行测试表明了该方法的有效性。%  The vision subsystem is one of the most important parts in the football robot system. The vision sub⁃system mainly includes real-time, accuracy and adaptability. This paper completes the anti-interference process⁃ing mainly from three aspects. The First is light interference. The paper uses a color extract algorithm which combines RGB color space and HSI color space. Using RGB color model to collect image, it is transformed into HSI color model immediately. The HSI color model is not sensitive to light, so it can be used for color calibra⁃tion. The second is the color impurity. Based on the HSI color model, the picture is dealt with to eliminate the noise by erosion and dilation. The authors of this paper select the most appropriate spatial color model conver⁃sion to reduce impurities interference effects. The third is some color interference surrounding the match field. Some solutions have been reached in this paper. According to the actual environment, the best one is selected to eliminate environmental interference. The actual running tests show the effectiveness of the image process method.

  10. Software Anti-jamming Technology in Application of the Design of Monolithic Integrated Circuit System%软件抗干扰技术在单片机系统设计中的应用

    Institute of Scientific and Technical Information of China (English)

    崔萃

    2009-01-01

    该文探讨了软件抗干扰技术研究的主要问题,系统分析了单片机系统设计中的软件抗干扰技术,对常用的指令冗余、拦截以及看门狗等设计方法进行了深入研究,并给出了具体的实现方法,对实际应用具有一定的指导作用.

  11. Anti-Jamming Modulation/Demodulation Technology of Atmospheric Laser Communication System%一种大气激光通信系统抗干扰调制/解调技术

    Institute of Scientific and Technical Information of China (English)

    刘丹; 刘智; 王璞瑶; 姜会林

    2012-01-01

    空间光通信以大气为介质进行信息传输时,不可避免地受到大气散射、大气湍流及背景光等因素的影响.针对大气信道对通信质量的影响,提出了基于激光偏振态参数的调制与解调技术,设计了一种基于偏振移位键控(PolSK)的大气激光通信系统并对其原理进行了简要分析.该通信系统采用偏振移位键控的调制方式,即利用圆偏振光的两种旋态(左旋和右旋)进行编码、调制从而实现数据的传输,接收端采用平衡探测方法进行光信号解调.对系统性能进行仿真分析,结果表明,基于激光偏振态参数的调制与解调技术在抗大气环境干扰、提高数据传输速率和降低误码率等方面具有优越性,在未来的空间激光通信领域有广阔的发展空间和应用前景.%When free space optical communication system uses the atmosphere as a medium for information transmission, received signals are inevitably influenced by the atmospheric environment, atmospheric turbulence, background light factors, and so on. Considering that the atmosphere channel has a great influence on the laser atmosphere communication quality, a modulation/demodulation technology based on polarization parameters is proposed, and an atmospheric laser communication system based on polarization shift keying (PolSK) is designed. This system uses polarization shift keying modulation. In this modulation, two rotation states of circle polarization (left and right) are used for information transmission. In the receiver, the optical signal is detected with balance detection method. At the same time, the performance of the system is simulated. The results show that the modulation/demodulation techniques based on polarization parameters have unique advantages, such as anti-atmospheric interference, high data rate and low bit error rate. It will have broad prospects for development and application in future space laser communication.

  12. The Anti-jamming Measures of Low Voltage Power Line Carrier Communication%低压电力线载波系统中的抗干扰措施

    Institute of Scientific and Technical Information of China (English)

    马宏锋; 陈金鹏

    2001-01-01

    According to the noises and interference in low power line, thispaper takes the measures from hardware and software. And it fits very well for restraining the noises and interference. It has been applied to the low vol tage power line carrier communication system, and obtained the anticipated effect.%根据低压电力线路存在的各种噪声和干扰,从硬件和软件等方面提出了相应的解决方案,并在低压电力线载波数据传输系统中得以应用,取得了预期的效果。

  13. Design and Practice of Anti-jamming Optimization for Radar Servo System%雷达伺服系统抗干扰优化设计与实践

    Institute of Scientific and Technical Information of China (English)

    万霞

    2011-01-01

    随着雷达机动性的不断提高,雷达的伺服系统涵盖的内容也越来越全面、复杂。包括天线转动平台的自动调平,天线旋转和定位,天线展开和撤收,方位角度转换及与上位机进行信息交换,强电、弱电综合,数字信号、模拟信号汇集等功能。因此要求综合全面地考虑各种因素,采取多种措施,解决其电磁兼容性问题,保证雷达及其伺服系统稳定可靠地运行。%With the improvement of radar mobility,what involved in the radar servo subsystem is more and more complicated.It includes functions such as automatic leveling of antenna rotary platform,rotation and location of antenna,deployment and dismantling of antenna,azimuth angle conversion and information exchange with master computer,integration of weak power and strong power,collection of digital signal and analog signal.Therefore,all factors should be considered and several measures should be taken to meet the requirements of electromagnetic compatibility and to ensure reliable operation of the radar system and its servo subsystem.

  14. Anti-Jamming Measures for Information Facility in Manned Space Flight Launching Site%载人航天发射场信息设备抗干扰措施

    Institute of Scientific and Technical Information of China (English)

    杨振国; 王勤

    2005-01-01

    介绍了造成载人航天发射场信息系统计算机网络硬件损坏和运行不正常的主要因素.提出信息系统计算机网络采用TT供电系统以及装设防雷击、防干扰容性隔离变压器,可综合解决防雷击、防电磁干扰、防谐波干扰、防地电位升高问题,确保信息系统计算机网络的安全可靠性.

  15. Tracking Launch Vehicles in Interference and Jamming Project

    Data.gov (United States)

    National Aeronautics and Space Administration — MARK Resources proposes to develop a method for combining a set of distributed FRPAs into a network that provides high GPS anti-jam/interference capability. Like a...

  16. In PT6964 Chip as Display Driver EFT Interference Measures%以PT6964芯片作为显示驱动的EFT抗干扰措施

    Institute of Scientific and Technical Information of China (English)

    廖炎光

    2014-01-01

    This paper introduces the display driver chip microcontroller with PT6964LED in the application of several anti-jamming measures.%主要介绍了单片机与PT6964LED显示驱动芯片在应用中的几种抗干扰措施。

  17. Enabling short fragments for uncoordinated spread spectrum communication

    DEFF Research Database (Denmark)

    Ahmed, Naveed; Pöpper, Christina; Capkun, Srdjan

    2014-01-01

    Uncoordinated spread spectrum (USS) protocols have been proposed for anti-jamming communication in wireless settings without shared secrets. The existing USS protocols assume that fragments of hundreds of bits can be transmitted on different channels in order to identify fragments that belong...

  18. A Hybrid Structured Multistage Wiener Filter for GPS Interference Suppression

    Directory of Open Access Journals (Sweden)

    Qing-Dong Huang

    2013-11-01

    Full Text Available To suppress the influence of impulsive noise spikes (outliers from the direction of arrival of the desired GPS signals, a combination of the Householder multistage Wiener filter (HMSWF and the recently introduced Minimum Module Cascaded Canceller (MMCC is employed to compose a hybrid structured HMSWF (HS-HMSWF method. The enhanced algorithm is employed by space-time anti-jamming processing in GPS receiver, with the ability of natural protection against the impulsive noise spikes influence of weights calculation. In space signal processing, it can avoid the zero pitch formed at the direction of target signal, and prevent the desired signal be diminished. Simulation results demonstrated the favorable anti-jamming performance of the proposed algorithm.  

  19. Weighing and control of bulk material in ship-lading process at harbor

    International Nuclear Information System (INIS)

    The author describes a new weighing and control system for bulk material in ship-loading process at harbor. It adopts nuclear radiation measurement, computer control and digital signal process techniques to weigh the bulk material with no-touch with the advantages of stability and anti-jamming. The measure accuracy reaches to 0.5% - 1.0%. It is was applicable in the bad condition of ship-loading spot at harbor

  20. Precise Location Technology Based on Chirp Spread Spectrum

    Directory of Open Access Journals (Sweden)

    Yan Zhang

    2011-06-01

    Full Text Available This article introduces chirp spread spectrum technology (CSS for short and optimized location algorithm. Symmetric double-sided two way ranging technique (SDS–TWR for short is applied to improve accuracy and range of measurement. Linear frequency modulation ranging technology utilizes protocols combining CSMA / CA and TDMA, and adjusts dynamically transmission rate and frame length according to noise, interference and multipath to ensure optimal throughput and accurate distance information. System has anti-jamming capability and covers great distance.

  1. Decision feedback equalizer based on non-singleton fuzzy regular neural networks

    Institute of Scientific and Technical Information of China (English)

    Song Heng; Wang Chen; He Yin; Ma Shiping; Zuo Jizhang

    2006-01-01

    A new equalization method is proposed in this paper for severely nonlinear distorted channels. The structure of decision feedback is adopted for the non-singleton fuzzy regular neural network that is trained by gradient-descent algorithm. The model shows a much better performance on anti-jamming and nonlinear classification, and simulation is carried out to compare this method with other nonlinear channel equalization methods. The results show the method has the least bit error rate (BER).

  2. Advancements on Radar Polarization Information Acquisition and Processing

    Directory of Open Access Journals (Sweden)

    Dai Dahai

    2016-04-01

    Full Text Available The study on radar polarization information acquisition and processing has currently been one important part of radar techniques. The development of the polarization theory is simply reviewed firstly. Subsequently, some key techniques which include polarization measurement, polarization anti-jamming, polarization recognition, imaging and parameters inversion using radar polarimetry are emphatically analyzed in this paper. The basic theories, the present states and the development trends of these key techniques are presented and some meaningful conclusions are derived.

  3. 变频器中单片机人机交互系统的设计%Design of Single-chip Human-machine Interface in Converter

    Institute of Scientific and Technical Information of China (English)

    陈林; 侯志雄; 熊有伦

    2000-01-01

    介绍了一种采用80196设计的变频器人机交互系统,包括系统的硬件、软件设计和抗干扰设计。%A human-machine system of converter is described in this paper, and the hardware, software and anti-jamming design of this singlechip system are discussed.

  4. 基于平均可工作概率的星间链路整网抗干扰性能评估方法%Performance evaluation method based on average availability for inter-satellite links system

    Institute of Scientific and Technical Information of China (English)

    韩其位; 聂俊伟; 刘文祥; 王飞雪

    2013-01-01

    Independent and autonomous running of the entire GNSS system in navigation warfare is one of the most important aims of building inter-satellite links.However,it is inevitable that inter-satellite links will be faced with the threats from jams in navigation warfare,which may result in performance declining,or even breaking down.Therefore,exact evaluation of anti-jamming performance is very important.Anti-jamming performance evaluation of inter-satellite links system is much more difficult than other objects,as it is related to almost every aspect of the system,such as the design of signal system,network,linking strategy,equipment performance,and so on.In order to accurately evaluate the antiinterference performance of the entire inter-satellite links network under the conditions of navigation warfare,this study firstly analyzed a variety of factors which affect the anti-jamming performance of inter-satellite links.On this basis,test scenarios for anti-jamming performance evaluation was modeled and designed.And then an evaluation method for anti-jamming performance of inter-satellite links system based on average availability was proposed,and the index system for availability evaluation was defined,which made accurate and quantitative evaluation of anti-jamming performnce of the entire inter-satellite links network possible.%导航战条件下的全系统自主导航运行是卫星导航系统星间链路建设的重要目标之一.对星间链路在导航战情况下的工作性能进行准确评估具有非常重要的意义.星间链路的整网抗干扰性能与单星抗干扰能力、星间信号体制、建链策略、网络体制等多种因素均有关系,比较复杂,从而为其准确评估带来很大困难.为准确评估导航战条件下星间链路的整网抗干扰性能,对影响星间链路整网抗干扰性能的各种因素进行分析,并在此基础上对整网抗干扰性能评估场景进行建模设计.提出了以干扰场景遍历条件

  5. Application of watersheds algorithms to train wheel tread check and measure systems

    Science.gov (United States)

    Shen, Bangxing; Zhang, Haibo; Wang, Wei

    2006-11-01

    A image system and a new kind of image processing algorithm (watersheds algorithm) are introduced; First, we get the prime wheel tread data by a Charge Coupled Device (CCD), after the pretreatment of the data, we use the watersheds algorithm to get the trail wheel abrasion and peel off strips, than we will get the numerical value of the damage. The result of the experiment shows that the system can obtain the edge of the trail wheel abrasion and peel off strips; the algorithm is fast, stable and anti-jamming; the recognition system can satisfy the manufactory requirements.

  6. Jamming in the Internet of Things: A Game-Theoretic Perspective

    OpenAIRE

    Namvar, Nima; Saad, Walid; Bahadori, Niloofar; Kelley, Brian

    2016-01-01

    Due to its scale and largely interconnected nature, the Internet of Things (IoT) will be vulnerable to a number of security threats that range from physical layer attacks to network layer attacks. In this paper, a novel anti-jamming strategy for OFDM-based IoT systems is proposed which enables an IoT controller to protect the IoT devices against a malicious radio jammer. The interaction between the controller node and the jammer is modeled as a Colonel Blotto game with continuous and asymmetr...

  7. Application of the Algorithm of Fractional Dimension to Extraction Image Edge

    Institute of Scientific and Technical Information of China (English)

    Qiang Luo; Qingli Ren

    2006-01-01

    The idea of fractional dimension was stated in brief firstly. Then, adopting the fractional statistical similar principle,the method of the least square minimum error was applied to evaluate the fractional dimension of per image pixel depending on the fractional property of image. And the image edge is extracted by magnitude of fractional dimension of image pixel. We presented the algorithm of the local fractional dimension, which made the rule of window size and sentencing the fractional dimension of edge. Although this algorithm was waste time, it is better than the classical ones in extraction edge and anti-jamming.

  8. Design of CAN Bus Dashboard on Mini EV%电动微型汽车的CAN总线仪表板设计

    Institute of Scientific and Technical Information of China (English)

    王秀青

    2012-01-01

    基于CAN总线技术设计完成了电动微型汽车仪表板,并针对CAN总线技术的优势进行了论述.同时简要介绍了仪表板采用的抗干扰措施。%The dashboard on mini EV has been designed based on the CAN bus technology, the advantages of that are described and the anti-jamming measures for the dashboard are briefly introduced.

  9. 一类最优调频序列的线性复杂度(英文)

    Institute of Scientific and Technical Information of China (English)

    高军涛; 胡予濮; 李雪莲

    2011-01-01

    For the anti-jamming purpose,frequency hopping sequences are required to have a large linear span. In this paper,we firstly give the linear span of a class of optimal frequency hopping sequences. The results show that the linear span is very small compared with their periods. To improve the linear span,we transform these optimal frequency hopping sequences into new optimal frequency hopping sequences with large linear span by using a general type of permutation polynomials over a finite field. Furthermore,w...

  10. Design principle of integrated direct digital sensor of rotation rate and torque

    Science.gov (United States)

    Zhang, Xiaoning; Geng, Chunming; Fu, Yongling

    2006-11-01

    Based on measuring technique of ordinary sensor of rotation rate and torque, this article mainly studied the sensing element of CMF (Coriolis Mass-Flow Meter), and designed for the prototype an IDDSRT (Integrated Direct Digital Sensor of Rotation Rate and Torque) that consists of torsion-bar spring, measuring fluted disc, and photoelectric sensing device. The sensor measures with high-frequency pulse. This design reduces the factors that affect the measuring, completely realizes non-contact digital measurement, greatly improves the anti-jamming ability and the measuring stability, and therefore increases measuring accuracy.

  11. STUDY ON MECHANISM OF HYDRODYNAMIC OSCILLATION IN VORTEX PRECESSION METER USING LARGE EDDY SIMULATION

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In order to improve the anti-jamming performance of a vortex precession meter, the disciplinarian of the vortex precession and the mechanism of hydrodynamic oscillation inside the vortex precession meter are numerically investigated by using the large eddy simulation. The results show that the periodical eccentric motion of the vortexes initiates a hydrodynamic oscillation inside the vortex precession meter. The visualized time dependent flow fields indicate that the pressures at axisymmetric points oscillate with a same intensity and frequency but 180° phase shift. By using differential sensing technique,a new prototype of double-sensor vortex precession meter,aimed to improve measurement accuracy, is developed.

  12. A Robust Acquisition Scheme for FH Signal in Adverse Environments

    Institute of Scientific and Technical Information of China (English)

    Ya-Ding Chen; Shao-Qian Li; Yu-Fan Cheng; Gang Wu

    2009-01-01

    Both partial-band jamming and multi- tone jamming have severe effect on the acquisition of frequency-hopping (FH) signal in adverse environments. In this paper, an anti-jamming FH signal acquisition scheme based on cognitive correlation process is proposed to boost the robustness of acquisition. The main idea of this scheme is to utilize a priori knowledge of FH speed and FH pattern to distinguish jamming signal from received signal. Furthermore, theoretic analysis on detection probability and false probability is given to demonstrate the robust performance of the FH signal acquisition method compared with conventional acquisition scheme without any prior information on FH speed and pattern in adverse environments.

  13. A method of initial welding position guiding for arc welding robot based on visual servo control

    Institute of Scientific and Technical Information of China (English)

    郭振民; 陈善本; 邱涛; 吴林

    2003-01-01

    In order to solve the visual guiding task of initial welding position for arc welding robot, this paper presents a practice-prone image-based visual servo control strategy without calibration, and we perform validating experiments on a nine-DOF arc welding robot system. Experimental results illustrate presented method has the function to fulfill the task of welding robot initial positioning with certain anti-jamming ability. This method provides a basis for guiding welding gun to initial welding pose with real typical seam's image properties to replace flag block properties, and is a significant exploit to realize visual guiding of initial welding position and seam tracing in robot welding system.

  14. 阀控液压马达速度伺服系统仿真分析%Simulation of the Hydraulic Motor of Speed Servo System Controlled by Valve

    Institute of Scientific and Technical Information of China (English)

    贾文铜; 周瑞祥; 张忠

    2012-01-01

    针对干扰力矩对阀控液压马达速度伺服系统的影响,利用结构不变性原理给系统加入了补偿器来消除干扰力矩的影响,同时利用PID控制来提高系统的抗干扰性.仿真表明,在利用结构不变性原理后再通过PID控制可以有效提高系统抗干扰能力和控制精度.%Aiming at the interfere moment affecting the hydraulic motor of speed servo system controlled by valve,the structure unchangeable principle was applied to eliminate the effect of the interfere moment and PID control was also managed to enhance the anti-jamming of the system, The simulation indicates that the application of the PID controll after the application of structure unchangeable principle can effectively improve the anti-jamming ability and control precision.

  15. The Development of Intelligent Detector for Train Longitudinal Impact

    Institute of Scientific and Technical Information of China (English)

    TIAN E; MO Yimin; NIU Wei

    2006-01-01

    This paper introduces a new kind of train impact detecting system that detect the train impact through detecting the train running acceleration, proposes that uniting the train running acceleration and the change rate of acceleration to token the train impact. The detector takes the portable computer as platform of data processing, utilizes the database technology to process data, making instrument Pc true, and improving the data processing ability of the instrument. The detector can show the train running acceleration on-line and real-timely, indicating the train impact situation directly,and uses the method that the software and hardware unifies to strengthen the system anti-jamming ability. At present, this detector has been tryout in some locomotive depots, each design function and the performance index conforms to request of the scene; the anti-jamming ability is strong, the monitor precision is reasonable, the detector can carry out the on-line examination to the train impact and monitoring the train running condition.

  16. Communication and control technology of underwater vehicle%水下机器人通信与控制技术研究

    Institute of Scientific and Technical Information of China (English)

    杨薇

    2015-01-01

    Research the development process of underwater vehicle, this article proposed vehicle system design with a track and designed the automotive module and algorithm control. Then contrast pulse modulation, differential pulse modulation, made use of improved underwater communication DPPM. Finally, experiments show that this method improves the data transfer rate. Add white noise to simulation experiment. When the signal is superimposed, anti-jamming capability of system would first become strong, with the increase in data, anti-jamming capability was weakened.%通过调研水下机器人的发展历程,提出了带有履带机器人的系统设计方案,并对其车载模块进行设计以及算法控制。然后通过对脉冲调制、差分脉冲调制进行对比,提出利用改进的 DPPM 进行水下通信,最后通过实验说明此种方法提高了数据的传输速率,添加白噪声进行实验仿真,说明当信号因延迟为叠加时,系统抗干扰能力会先变强,然后随着叠加数据的增多,抗干扰性减弱。

  17. Cascade connection serial parallel hybrid acquisition synchronization method for DS-FHSS in air-ground data link

    Science.gov (United States)

    Wang, Feng; Zhou, Desuo

    2007-11-01

    In air-ground tactical data link system, a kind of primary anti jamming technology adopted is direct sequence - frequency hopping spread spectrum (DS-FHSS) technology. However, how to implement the quick synchronization of DS-FHSS is an important technology problem, which could influence the whole communication capability of system. Thinking of the application demand of anti jamming technology in actual, a kind of cascade connection serial parallel hybrid acquisition synchronization method is given for the DS-FHSS system. The synchronization consists of two stages. The synchronization of FH communication is adopted at the first stage, and the serial parallel hybrid structure is adopted for the DS PN code synchronization at the secondary stage. Through calculating the detect probability of the FH synchronization acquisition and the acquisition time of DS code chip synchronization, the contribution to the synchronization capability of system by this method in this paper is analyzed. Finally, through simulating on computer, the performance estimate about this cascade connection serial parallel hybrid acquisition synchronization method is given.

  18. 转发式干扰下卫星数据链效能分析与仿真%Efficiency Analysis and Simulation for Satellite Data Link in Retransmitted Jamming

    Institute of Scientific and Technical Information of China (English)

    朱林; 方胜良; 孙晓军; 吴付祥

    2014-01-01

    According to the practical application of satellite data link on unmanned aerial vehi-cle, several common anti-jamming methods are researched. The weakness and combat strategy of anti-jamming method is analyzed. Correlation interference is proposed to interfere to satellite data link. The retransmitted jamming model based on delay is built. The efficiency of satellite data link in the presence of retransmitted jamming is analyzed and simulated. Finally, the simu-lation result shows the feasibility of this method for jamming satellite data link.%针对无人机上卫星数据链的实际应用情况,研究了卫星数据链的常用抗干扰措施,分析了各抗干扰措施的弱点及对抗策略,提出采用相关性干扰对抗卫星数据链,构建了基于时延的转发式干扰模型,对转发式干扰下的卫星数据链效能进行了分析和仿真。仿真结果显示,该方法能够有效对抗卫星数据链,具有一定的可行性。

  19. Band Selection for Aircraft Targets Detection%面向飞机目标探测的波段选择方法

    Institute of Scientific and Technical Information of China (English)

    祁鸣; 刘德连; 张二磊

    2011-01-01

    针对飞机目标的探测与抗干扰问题,提出一种新的面向飞机目标探测的波段选择方法,通过耦合分析飞机目标、背景、大气、成像系统和干扰的特性,建立目标和背景的信噪比模型,确定出探测波段的中心.在此基础上,不断扩展探测波段,并分析信噪比的变化,得到探测波段的宽度.随后,根据干扰目标的辐射特性,添加抗干扰波段,有效解决了目标探测和抗干扰的结合.将所选择的探测波段应用于飞机目标的探测,仿真结果表明我们给出的波段选择方法得到的探测波段能够提高系统探测距离,同时具有一定的抗干扰能力.%To improve the performance of detection and anti-jamming of aircraft targets, a new band selection method is proposed. Base on the coupling analysis of the characteristics of aircraft targets, background, atmosphere, detection systems, and infrared-decoy, a signal to noise model (SNR) is build. And the center of the selected band is determined. Next, the width of the selected band is enlarged step by step to show the change of the SNR. As the SNR grows slowly and flatly, the width of the selected band is the final selected band. Subsequently, the characteristics of infrared-decoy are also analyzed. And a supplement band is got for anti-jamming. We test the band selection method by applying our selected bands to aircraft targets detection. The results indicate that the selected bands obtained by our new band selection method can improve the detection performance of aircraft targets and have good ability for Anti-jamming.

  20. Isothermal amplification detection of nucleic acids by a double-nicked beacon.

    Science.gov (United States)

    Shi, Chao; Zhou, Meiling; Pan, Mei; Zhong, Guilin; Ma, Cuiping

    2016-03-01

    Isothermal and rapid amplification detection of nucleic acids is an important technology in environmental monitoring, foodborne pathogen detection, and point-of-care clinical diagnostics. Here we have developed a novel method of isothermal signal amplification for single-stranded DNA (ssDNA) detection. The ssDNA target could be used as an initiator, coupled with a double-nicked molecular beacon, to originate amplification cycles, achieving cascade signal amplification. In addition, the method showed good specificity and strong anti-jamming capability. Overall, it is a one-pot and isothermal strand displacement amplification method without the requirement of a stepwise procedure, which greatly simplifies the experimental procedure and decreases the probability of contamination of samples. With its advantages, the method would be very useful to detect nucleic acids in point-of-care or field use. PMID:26706801

  1. Power Transformer Intelligence Monitor System

    Institute of Scientific and Technical Information of China (English)

    Sun Jianshe; Shi Lei

    2006-01-01

    An auto-monitoring system has been created that could monitor the main parameter of power transformers. It reads data of V&I by precision rectifier circuit and amplifier, and converted electric energy into pulse signal by means of sensor technique and pulse converter circuit, it is sent into microcomputer to process, completed monitoring to power transformer parameters and running state by software system. It can register all kinds of key data, and provide all kinds of virtual technical data for managing sections and can auto-form all kinds of electric annual reports and monthly reports analysis graphs such as managing graphs. It notably improves the safety and reliability of transformer, with strong anti-jamming technique and unique function, it can be used on the transformers in railway' s self-closing lines and all kinds of transformer stations.

  2. Packaged silica microsphere-taper coupling system for robust thermal sensing application.

    Science.gov (United States)

    Yan, Ying-Zhan; Zou, Chang-Ling; Yan, Shu-Bin; Sun, Fang-Wen; Ji, Zhe; Liu, Jun; Zhang, Yu-Guang; Wang, Li; Xue, Chen-Yang; Zhang, Wen-Dong; Han, Zheng-Fu; Xiong, Ji-Jun

    2011-03-28

    We propose and realize a novel packaged microsphere-taper coupling structure (PMTCS) with a high quality factor (Q) up to 5×10(6) by using the low refractive index (RI) ultraviolet (UV) glue as the coating material. The optical loss of the PMTCS is analyzed experimentally and theoretically, which indicate that the Q is limited by the glue absorption and the radiation loss. Moreover, to verify the practicability of the PMTCS, thermal sensing experiments are carried out, showing the excellent convenience and anti-jamming ability of the PMTCS with a high temperature resolution of 1.1×10(-3) ◦C. The experiments also demonstrate that the PMTCS holds predominant advantages, such as the robustness, mobility, isolation, and the PMTCS can maintain the high Q for a long time. The above advantages make the PMTCS strikingly attractive and potential in the fiber-integrated sensors and laser. PMID:21451600

  3. Performance Evaluation of the New Compound-Carrier-Modulated Signal for Future Navigation Signals

    Directory of Open Access Journals (Sweden)

    Ruidan Luo

    2016-01-01

    Full Text Available Navigation Signal based on Compound Carrier (NSCC, is proposed as the potential future global navigation satellite system (GNSS signal modulation scheme. NSCC, a kind of multi-carrier (MC signal, is generated by superposition and multi-parameter adjustment of sub-carriers. Therefore, a judious choice of parameter configation is needed. The main objective of this paper is to investigate the performance of the NSCC which is influenced by these parameters and to demonstrate its structure characteristics and superiority, employing a comprehensive evaluation system. The results show that the proposed NSCC signal processes full spectral efficiency and limited out of band (OOB emissions, satisfying the demands of crowed frequency resources. It also presents better performance in terms of spectral separation coefficients (SSCs, tracking accuracy, multipath mitigation capability and anti-jamming reduction compared with the legacy navigation signals. NSCC modulation represents a serious candidate for navigation satellite augmentation systems, especially for signals applied in challenging environments.

  4. Brushless DC Motor Control System Design Based on DSP2812

    Directory of Open Access Journals (Sweden)

    Wei Min

    2016-01-01

    Full Text Available By comparison various control methods currently for permanent magnet brushless DC motor, on the basis of motor principle analysis, a current smallest and most real-time all-digital rare earth permanent magnet brushless DC motor control system is designed. The high-speed digital signal processor DSP2812 is applied as the main control unit. The fuzzy PID control algorithm is used to control rectifier regulator and speed, which the speed and current is double closed loop in the system. The principle of control system, control strategy and software is analyzed in this paper. The system has some features such as less overshoot, rapid response speed, good performance of anti-jamming, simple structure, high control precision, flexible in changing control policies and so on. Validity of the design is verified by prototype test.

  5. A New Method to Improve the Precision of SO2Measurement in Atmosphere

    Science.gov (United States)

    Gong, R. K.; Chen, L.; Nian, S. P.

    2006-10-01

    The thesis discusses the status quo and existent problems of SO2 measurement, explores sensor mechanism of measurement precision of SO2, and deduces the mathematical measurement model of SO2 according to Lambert-Beer Law. Aiming at the nonlinearity problem existing in the mathematical model, it employs Taylor's series expansion to resolve the problem. In addition, it designs the gas room of double optical paths to measure SO2 by infrared, which utilizes four detectors to eliminate the impact of CO2 and disturbed noise by receiving signals. Finally, through the analysis of the experimental data, it proves that this method has such features as easy implementation, high precision, strong anti-jamming capability, and real-time and on-line measurement of SO2required in the industry field.

  6. Circular object recognition based on shape parameters

    Institute of Scientific and Technical Information of China (English)

    Chen Aijun; Li Jinzong; Zhu Bing

    2007-01-01

    To recognize circular objects rapidly in satellite remote sensing imagery, an approach using their geometry properties is presented.The original image is segmented to be a binary one by one dimension maximum entropy threshold algorithm and the binary image is labeled with an algorithm based on recursion technique.Then, shape parameters of all labeled regions are calculated and those regions with shape parameters satisfying certain conditions are recognized as circular objects.The algorithm is described in detail, and comparison experiments with the randomized Hough transformation (RHT) are also provided.The experimental results on synthetic images and real images show that the proposed method has the merits of fast recognition rate, high recognition efficiency and the ability of anti-noise and anti-jamming.In addition, the method performs well when some circular objects are little deformed and partly misshapen.

  7. Reed Solomon Coding for Frequency Hopping Spread Spectrum in Jamming Environment

    Directory of Open Access Journals (Sweden)

    Othman Sidek

    2008-01-01

    Full Text Available Frequency hopping spread spectrum with noncoherent M-ary frequency shift keying system is considered. In this study Reed Solomon codes RS (255, 223 are employed in a standard error correction role to provide some Anti-Jamming (AJ capability with 8-bit symbols. Noise has been added to RS encoded data, which is demodulated at RS decoder perfectly. Matlab simulations have been implemented for numerical results. Graphical results have been plotted between the probability of an erasure versus ρ using RS (255, 223 code for 1 and 2 kHz frequencies. The simulation results have proved that system having RS (255, 223 code with M = 32 require substantially less signal to jammer power ratio to achieve the same bit error probability.

  8. Isothermal amplification detection of nucleic acids by a double-nicked beacon.

    Science.gov (United States)

    Shi, Chao; Zhou, Meiling; Pan, Mei; Zhong, Guilin; Ma, Cuiping

    2016-03-01

    Isothermal and rapid amplification detection of nucleic acids is an important technology in environmental monitoring, foodborne pathogen detection, and point-of-care clinical diagnostics. Here we have developed a novel method of isothermal signal amplification for single-stranded DNA (ssDNA) detection. The ssDNA target could be used as an initiator, coupled with a double-nicked molecular beacon, to originate amplification cycles, achieving cascade signal amplification. In addition, the method showed good specificity and strong anti-jamming capability. Overall, it is a one-pot and isothermal strand displacement amplification method without the requirement of a stepwise procedure, which greatly simplifies the experimental procedure and decreases the probability of contamination of samples. With its advantages, the method would be very useful to detect nucleic acids in point-of-care or field use.

  9. Design of object surveillance system based on enhanced fish-eye lens

    Institute of Scientific and Technical Information of China (English)

    Jianhui Wu; Kuntao Yang; Qiaolian Xiang; Nanyang Zhang

    2009-01-01

    A new method is proposed for the object surveillance system based on the enhanced fish-eye lens and the high speed digital signal processor (DSP). The improved fish-eye lens images an ellipse picture on the charge-coupled device (CCD) surface, which increases both the utilization rate of the 4:3 rectangular CCD and the imaging resolution, and remains the view angle of 183°. The algorithm of auto-adapted renewal background subtraction (ARBS) is also explored to extract the object from the monitoring image. The experimental result shows that the ARBS algorithm has high anti-jamming ability and high resolution, leading to excellent object detecting ability from the enhanced elliptical fish-eye image under varies en-vironments. This system has potential applications in different security monitoring fields due to its wide monitoring space, simple structure, working stability, and reliability.

  10. Design of new seismometer based on laser Doppler effect

    Institute of Scientific and Technical Information of China (English)

    Zhenhui Du(杜振辉); Fuxiang Huang(黄福祥); Chengzhi Jiang(蒋诚志); Zhifei Tao(陶知非); Hua Gao(高华); Lina Lü(吕丽娜)

    2004-01-01

    In order to improve the resolution of seismic acquisition, a new seismic acquisition system based on tangential laser Doppler effect with an optimized differential optical configuration is proposed. The relative movement of the inertia object and the immobile frame is measured by laser Doppler effect, which can avoid the electromagnetic and thermometric interference, and the adoption of frequency-modulated (FM)transmission can improve the ability of anti-jamming. The frequency bandwidth is properly determined by analyzing the frequency of the Doppler signal. The velocity, displacement, acceleration, and frequency to be measured can be real-time acquired by frequency/velocity (F/V) converting the FM Doppler signal.A 100-dB dynamic range and the linear frequency range of 1.0 to 1000 Hz are realized.

  11. Strategy and Consider for Hosting Type Data Center Users%托管数据中心用户的策略和考虑

    Institute of Scientific and Technical Information of China (English)

    陈宇通

    2012-01-01

    主要阐述了用户如何决策使用托管型的数据中心。并从安全性、节能、抗干扰、高效安装等几方面对布线设计和方案实施提出了合理化建议,以给数据中心用户决策提供参考。%The user to how to carry on the decision-making for use hosting type data center was mainly discussed. And some rational suggestions for wiring design and plan implementation were given, from the aspects of safety, energy saving, anti-jamming, high efficiency installation. It can provide references for users' decision making.

  12. Guiding the welding robot to the initial welding position with visual method

    Institute of Scientific and Technical Information of China (English)

    Zhu Zhenyou; Lin Tao; Chen Shanben

    2008-01-01

    Using step pattern match technology with variational resolution can recognize the position and orientation of the weld seam in the image. According to using the image segmentation method based on pattern match, not only advanced the speed and anti-jamming capability, but also captured the edge information of the weld seam and the edge of the workpiece, and the image coordinate of the initial welding position can be obtained. The matrix for hand-eye relationship of the robot can be calculated by adopting the rapid calculation method. According to the depth calculating principle with the special point matching using binocular stereovision, the initial welding position can be confirmed by calculating the middle point of the perpendicular line of two radials in the space, and the function to guide the welding robot to the initial welding position can be realized.

  13. Resilience of LTE networks against smart jamming attacks

    KAUST Repository

    Aziz, Farhan M.

    2014-12-08

    Commercial LTE networks are being studied for mission-critical applications, such as public safety and smart grid communications. In this paper, LTE networks are shown vulnerable to Denial-of-Service (DOS) and loss of service attacks from smart jammers, who may employ simple narrowband jamming techniques to attack without any need to hack the network or its users. We modeled the utilities of jamming and anti-jamming actions played by the jammer and the network under the framework of single-shot and repeated Bayesian games. In a single-shot game formulation the only Nash Equilibria (NE) are pure strategy equilibria at which network utility is severely compromised. We propose a repeated-game learning and strategy algorithm for the network that outperforms single-shot games by a significant margin. Furthermore, all of our proposed actions and algorithms can be implemented with current technology.

  14. Direct GPS P-Code Acquisition Method Based on FFT

    Institute of Scientific and Technical Information of China (English)

    LI Hong; LU Mingquan; FENG Zhenming

    2008-01-01

    Recently, direct acquisition of GPS P-code has received considerable attention to enhance the anti-jamming and anti-spoofing capabilities of GPS receivers. This paper describes a P-code acquisition method that uses block searches with large-scale FFT to search code phases and carrier frequency offsets in parallel. To limit memory use, especially when implemented in hardware, only the largest correlation result with its position information was preserved after searching a block of resolution cells in both the time and frequency domains. A second search was used to solve the code phase slip problem induced by the code frequency offset. Simulation results demonstrate that the probability of detection is above 0.99 for carrier-to-noise density ratios in excess of 40 dB- Hz when the predetection integration time is 0.8 ms and 6 non-coherent integrations are used in the analysis.

  15. Area Efficient Rapid Signal Acquisition scheme for High Doppler DSSS Signals

    Directory of Open Access Journals (Sweden)

    D. Karunakar Reddy

    2013-04-01

    Full Text Available The Direct Sequence Spread Spectrum (DSSS communication system is widely used in ground to airmissile links due to its anti-jam and low Signal to Noise Ratio (SNR requirement advantages. The paperpresents the challenges in achieving fast signal acquisition in this scenario and brings out theimplementation challenges for achieving simultaneous Doppler estimation and phase delay of PseudoNoise (PN code. A new scheme for PN code phase delay estimation with correlation of differential signals,followed by precise Doppler estimation using Fast Fourier Transform (FFT is presented. The areaoptimized Field Programmable Gate Array (FPGA friendly architecture is utilized for rapid signalacquisition by combining both time and frequency domain approaches. The advanced design practices inFPGAs are used to achieve resource sharing and high clock speed of operation. The architecture issynthesized for Virtex-6 LX240T FPGA, resulting in 52% of area occupancy and 134 MHz of maximumallowed clock frequency value.

  16. Research on a Sort of Ultrasonic Flowmeter%一种超声流量计的设计

    Institute of Scientific and Technical Information of China (English)

    乔静

    2012-01-01

    In this paper,an ultrasonic flowmeter is designed by the use of difference method.It can measure gas flux,which can avoid the shortcoming of touching flowmeter such as short utility time and discommodious installing.It has high precision,good anti-jamming ability and bright prospects for application.%本文采用时差法设计了一种超声流量计,用于测量气体的体积流量,避免了接触式流量计寿命短、安装不方便等缺点。该设计精度高,抗干扰能力强,具有广阔的应用前景。

  17. Research and application of visual location technology for solder paste printing based on machine vision

    Institute of Scientific and Technical Information of China (English)

    Luosi WEI; Zongxia JIAO

    2009-01-01

    A location system is very important for solder paste printing in the process of surface mount technology (SMT). Using machine vision technology to complete the location mission is new and very efficient. This paper presents an integrated visual location system for solder paste printing based on machine vision. The working principle of solder paste printing is introduced and then the design and implementation of the visual location system are described. In the system, two key techniques are completed by secondary development based on VisionPro.One is accurate image location solved by the pattern-based location algorithms of PatMax. The other one is camera calibration that is achieved by image warping technology through the checkerboard plate. Moreover, the system can provide good performances such as high image locating accuracy with 1/40 sub-pixels, high anti-jamming, and high-speed location of objects whose appearance is rotated, scaled, and/or stretched.

  18. The risk early-warning of gas hazard in coal mine based on Rough Set-neural network

    Institute of Scientific and Technical Information of China (English)

    TIAN Shui-cheng; WANG Li

    2007-01-01

    This article proposed the risk early-warning model of gas hazard based on Rough Set and neural network. The attribute quantity was reduced by Rough Set, the main characteristic attributes were withdrawn, the complexity of neural network system and the computing time was reduced, as well. Because of fault-tolerant ability, parallel processing ability, anti-jamming ability and processing non-linear problem ability of neural network system, the methods of Rough Set and neural network were combined. The examples research indicate: applying Rough Set and BP neural network to the gas hazard risk early-warning coal mines in coal mine, the BPNN structure is greatly simplified, the network computation quantity is reduced and the convergence rate is speed up.

  19. Mathematical principle and characteristics of polarization transform

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The precise definition of polarization transform is proposed from the viewpoint of polarization domain transform for the first time. The mathematical principle,char-acteristics and physical meanings of polarization transform are analyzed. Two typical kinds of polarization transforms which are called unitary matrix polarization transform (UMPT) and diagonal matrix polarization transform (DMPT) are put for-ward. The gain property and the change property of polarization state distance are presented in detail. Thereby,the concept of serial polarization transform is pro-posed. A general polarization transform can be realized by two steps: changing the location of polarization states in polarization domain by UMPT; and expanding or compressing the density of polarization states by DMPT. The result is meaningful to many applications including polarization filtering,detection,enhancement,anti-jamming,discrimination and so on.

  20. 自适应跳频MF-TDMA抗干扰卫星通信技术%Application of Adaptive Frequency-hopping in MF-TDMA Satellite Communication

    Institute of Scientific and Technical Information of China (English)

    吴果; 米丽

    2012-01-01

    In MF-TDMA satellite communication system, the termdnal has the capability of frequency hopping, and it is easy to improve the anti-jamming capability of system combining with frequency-hopping. The technical characteristics of MF-TDMA satellite communication and adaptive frequency hopping are analyzed and compared in this paper. Based on distributed interference detection and centralized frequency planning, an MF-TDMA adaptive frequency hopping (AFH-MF-TDMA) technique is put forward according to the analysis result. This technique can realize an accurate detection of interference and a more efficient allocation of frequencies. And it can effectively enhance anti-jamming performance of MF-TDMA satellite communication system.%MF-TDMA卫星通信系统中,网内终端本身具有频率跳变的能力,可以与跳频相结合实现抗干扰的目的。文章分析了MF-TDMA卫星通信和自适应跳频技术的特点,比较了两种常用的自适应跳频技术,并根据分析结果提出了一种基于分布式干扰检测、频点集中规划的自适应跳频MF-TDMA(AFH-MF-TDMA)卫星通信技术,该技术具有干扰检测准确、频率资源综合利用率高的特点,可以有效增强MF-TDMA卫星通信系统的抗干扰能力。

  1. 卫星扩频信号抗窄带干扰性能限研究%Research on Performance Bound Against Narrowband Interference of Satellite Spread Spectrum Signal

    Institute of Scientific and Technical Information of China (English)

    王明; 李长庚

    2015-01-01

    卫星扩频信号的抗干扰性能关系到卫星链路系统的安全性. 在高精度测距和有限星载处理能力约束下增加抗干扰环节会增加信号接收机复杂度并且引入测距误差,定量分析扩频测距中的天然抗窄带干扰能力可以为在什么条件下不需要采取抗干扰措施提供决策,对优化系统设计具有重要意义. 本文对扩频测距的抗窄带干扰性能限进行了定量计算、分析,设计了实验测试方法和系统,达到了预期目的.%The anti jamming performance of transceiver relations security of inter-satellite links sys-tem, under high precision ranging and limited spaceborne processing capacity, increasing anti-interfer-ence part will increase the complexity of the transceiver and the introducing ranging error, so quantitative analysing natural ability against narrowband interference of spread spectrum ranging can provide decision to not need to take anti-jamming measures, under what conditions. It is important for optimizing system design. The paper takes the performance bound of against interference of inter satellite link transceiver as the research target. Researching on the key technical issues by quantitative calculation, analysis, design experiment test method and system, achieved the desired purpose.

  2. Simulation of pulse modulated infrared air-to-air missile%脉冲调制式红外空空导弹仿真

    Institute of Scientific and Technical Information of China (English)

    黄鹤松; 童中翔; 李建勋; 王超哲; 柴世杰; 李慎波

    2014-01-01

    红外空空导弹仿真是空战效能评估的重点和难点。根据红外空空导弹的识别、制导、运动机理,建立了导弹模型,同时也建立了诱饵模型,对红外空空导弹进行仿真和抗干扰分析。该导弹模型主要由导引头制导方程组、导弹运动方程组、抗干扰方法等组成。根据建立的导弹模型仿真出了导弹的攻击区、导弹和靶机运动轨迹以及导弹的抗干扰性能,通过与真实导弹进行对比表明,仿真的红外空空导弹与真实的导弹性能指标基本吻合。%Infrared air-to-air missile simulation is an important and difficult part of air war performance evaluation.Based on identification,guidance,motion mechanism of infrared air-to-air missile,missile and infrared decoy model were established to simulation and anti-jamming analysis for infrared air-to-air missile.Missile model was composed by seeker guided equations,missile motion equations,anti-interference methods etc.Missile attack zone,missile and drone aircraft trajectories and anti-jamming performance were simulated according to the model.Contrasted with real missile,the calculation results are in good agreement with the experimental results.

  3. 大气机高度输出接口电路的设计%Design of Height Output Interface Circuit for Atmosphere Machine

    Institute of Scientific and Technical Information of China (English)

    侯民胜; 田宇

    2011-01-01

    为完成俄制大气机与国产航管应答机的交连,设计了由单片机、A/D转换器、电平转换电路、驱动电路、隔离电路和电源等电路组成的俄制大气机高度输出接口板电路.采取数据校准和抗干扰技术,简化硬件电路,提高高度数据转换精度和系统的抗干扰能力.实验表明,该接口电路实现了高度数据的数字化,能够将饿制大气机输出的模拟高度电平信号转换成满足国产航空应答机要求的数字编码信号.%In order to connect Russian-made atmosphere machine with the domestic ATC(Air Traffic Control) , a Russian-made height output interface circuit for atmosphere machine consisted of single chip microcomputer, A/D converter, level converter , driver circuit, isolator and electrical power was designed. The data correlation and anti-jamming technique were adopted to simplify hardware and to enhance conversion precision of height data and anti-jamming performance of the system. The test shows that the interface circuit can convert the analog height signal to digital encoding signal which is fit for the requirements of domestic ATC transponder.

  4. Performance analysis of DS/FH signals based on wideband ambiguity function%基于宽带模糊函数的DS/FH信号性能分析

    Institute of Scientific and Technical Information of China (English)

    孟生云; 杨文革

    2012-01-01

    The introduction of the hybrid DS/FH spread spectrum technology could enhance TTC systems electronic countermeasure capability.The expression of the wideband ambiguity function(WAF) is derived.It is known that,with carrier frequency increase,the difference between wideband and narrowband ambiguity function decrease for weakened signal duration impact on ambiguity function.However,signal duration change should be matched in the receiving signal processing.On the basis of the WAF expression,the performance of waveforms with various spreading gain assignment such as resolution,accuracy,sidelobe suppression and anti-jamming are simulated numerically and analyzed.Simulation results show that DS/FH signals possess almost ideal thumbtack AF plot with certain spreading gain assignment,and better resolution and anti-jamming performances would be obtained with relatively large FH spreading gain.%引入直扩/跳频(DS/FH)混合扩频技术可以增强航天测控系统的电子对抗能力。推导了DS/FH混合扩频信号的宽带模糊函数表达式。通过分析得知,随着载波频率的增加,信号时长的变化对模糊值的影响减弱,宽带和窄带模糊函数间的差异减小,但在接收信号的处理中仍需考虑对信号时长变化的匹配。数值仿真分析了DS/FH信号波形在不同增益分配下的分辨率、精度、旁瓣抑制及抗干扰等性能。结果表明在一定的增益分配下,该波形具有接近理想的图钉型模糊图,适当增加跳频增益可以获得更好的分辨率和抗干扰性能。

  5. NLMS算法在射电天文中的应用%Application of NLMS Algorithm in Radio Astronomy

    Institute of Scientific and Technical Information of China (English)

    李耀华; 程翥; 罗鹏飞

    2011-01-01

    Radio astronomy passively receives weak radio signals in the universe, which are susceptible to the impact of operational activities for active people. In order to suppress and eliminate the television signal interference during radio observing, the adaptive anti-jamming measures which always are applied in communication and radar field and two assistant antennae are used. Ths measures can greatly inhibit the television signal interference, improve signal-to-noise, and detect weak radio astronomy signals.%射电天文被动接收宇宙中极其微弱的射电信号,很容易受到人们有源业务活动的影响.为了抑制和消除射电望远镜观测过程中出现的电视信号干扰,采取了通常用在通信雷达领域的自适应抗干扰措施,利用两个辅助天线,极大地抑制了电视信号干扰,改善了信噪比,从而能够检测出微弱的射电天文信号.

  6. An Onboard Transmitting Antenna of Cruise Missile%一种飞航导弹弹载发射天线设计

    Institute of Scientific and Technical Information of China (English)

    何兵; 刘刚; 南楠; 王园园

    2011-01-01

    以飞航导弹弹载数据链为应用背景,通过综合分析、比较、优化和仿真,设计了一种与飞航导弹共形、具有大角域覆盖能力的弹载发射天线。仿真结果说明了该天线性能满足飞航导弹卫星通信需求,在解决工程实际问题的同时,为此类应用提供了一种新型天线方案,为相关设计提供了一种思路。%In the paper,we designed a kind of onboard transmitting antenna of cruise missile through integrated comparison,analysis,optimization and simulation.The antenna is conformal with the cruise missile,and has wide coverage domain and certain anti-jamming capability.The simulation result shows that the designed antenna satisfies all requirements of satellite communication of cruise missile.The paper provides a new antenna designning method and new idea for similar application.

  7. 多微处理器在管道焊接自动控制系统中的应用研究%Study on Application of Multi Microcomputer in Automatic Control System of Pipeline Welding Process

    Institute of Scientific and Technical Information of China (English)

    韩赞东; 都东; 陈强; 隋永莉; 程辉

    2001-01-01

    Based on multi-microcomputer,the automatic control system ofpipeline all-position welding process is developed.The system structure,working principle and software design are described.By serial communication,the cooperative control of welding parameters is realized between PLC and microcontroller.The hardware circuit of serial communication,PLC system configuration and the anti-jamming measure are also introduced. Experiments show that the system is reliable and can improve production efficiency,and has important engineering value and widely application foreground.%建立了基于多微处理器的管道全位置焊接自动控制系统,描述了其系统结构、工作原理和软件设计。通过串行通信,PLC和单片机之间实现了对焊接参数的协调控制。还介绍了串行通信的硬件电路、PLC系统设置和系统抗干扰措施等。实验表明,该系统运行可靠,能有效提高生产效率,具有重要的工程应用前景。

  8. FIJI: Fighting Implicit Jamming in 802.11 WLANs

    Science.gov (United States)

    Broustis, Ioannis; Pelechrinis, Konstantinos; Syrivelis, Dimitris; Krishnamurthy, Srikanth V.; Tassiulas, Leandros

    The IEEE 802.11 protocol inherently provides the same long-term throughput to all the clients associated with a given access point (AP). In this paper, we first identify a clever, low-power jamming attack that can take advantage of this behavioral trait: the placement of a low-power jammer in a way that it affects a single legitimate client can cause starvation to all the other clients. In other words, the total throughput provided by the corresponding AP is drastically degraded. To fight against this attack, we design FIJI, a cross-layer anti-jamming system that detects such intelligent jammers and mitigates their impact on network performance. FIJI looks for anomalies in the AP load distribution to efficiently perform jammer detection. It then makes decisions with regards to optimally shaping the traffic such that: (a) the clients that are not explicitly jammed are shielded from experiencing starvation and, (b) the jammed clients receive the maximum possible throughput under the given conditions. We implement FIJI in real hardware; we evaluate its efficacy through experiments on a large-scale indoor testbed, under different traffic scenarios, network densities and jammer locations. Our measurements suggest that FIJI detects such jammers in real-time and alleviates their impact by allocating the available bandwidth in a fair and efficient way.

  9. Signal Conditoning Circuit Application to Frequency Modulation Continuous Wave(FMCW) Radar%调频连续波(FMCW)雷达信号调理电路

    Institute of Scientific and Technical Information of China (English)

    汪红; 张杰; 张大彪

    2012-01-01

    文中给出一种应用于调频连续波(FMCW)雷达的信号调理电路.该电路采用低噪声前置放大器、对数主中放和具有频域压缩功能的滤波器.实验表明,该电路小信号增益大于100dB,动态范围大于80dB,具有较高的信噪比和优良的滤波性能,可有效地提高FMCW雷达的抗干扰能力.%A kind of signal conditoning circuit which applied to the frequency modulation continuous wave (FMCW) radar was proposed. The circuit adopted low noise pre-amplifier,logarithm intermediate-frequency (IF) amplifier and the filter with frequency dynamic compression. Experimental results show that the little signal gain is more than 100 dB and dynamic range is over 80 dB, which has higher signal-to-noise ratio(S/N) and good filter performance. The circuit can effectively improve the anti-jamming ability of FMCW radar.

  10. Models in frequency-hopping-based proactive jamming mitigation for space communication networks

    Science.gov (United States)

    Shen, Dan; Chen, Genshe; Pham, Khanh; Blasch, Erik; Tian, Zhi

    2012-06-01

    In this paper, we consider a cognitive radio based space communication system in a game-theoretical framework, where players dynamically interact through wireless channels to utilize the wideband spectrum for their objectives. The performance indices include data rate, covertness, jamming, and anti-jamming; each of which relate to an effective signal-nose-ratio (SNR). The game players have different intents and asymmetric and hierarchical information about the frequency spectrum which are modeled as three different types of players: primary users, secondary users, and hostile active jammers. We consider the informational asymmetry in two situations: (1) different information sets for friendly users and jammers and (2) even among the friendly sensors; some sensors may only have partial or little information about others due to jammed observations. Such an asymmetric information pattern naturally partitions the sensors into leaders and followers. In our hierarchical anti-jammer approach, a two level approach includes a pursuit-evasion game and a Stackelberg game. At the higher-level, a non-cooperative pursuit-evasion game is constructed to model the interactions between jammer and primary users in the frequency-location domains. At the lower level, primary and secondary users play a dynamic Stackelberg game in the presence of jammers. Theoretical game solutions are provided to demonstrate the proposed proactive jamming mitigation strategy.

  11. Coupled Integration of CSAC, MIMU, and GNSS for Improved PNT Performance.

    Science.gov (United States)

    Ma, Lin; You, Zheng; Liu, Tianyi; Shi, Shuai

    2016-05-12

    Positioning, navigation, and timing (PNT) is a strategic key technology widely used in military and civilian applications. Global navigation satellite systems (GNSS) are the most important PNT techniques. However, the vulnerability of GNSS threatens PNT service quality, and integrations with other information are necessary. A chip scale atomic clock (CSAC) provides high-precision frequency and high-accuracy time information in a short time. A micro inertial measurement unit (MIMU) provides a strap-down inertial navigation system (SINS) with rich navigation information, better real-time feed, anti-jamming, and error accumulation. This study explores the coupled integration of CSAC, MIMU, and GNSS to enhance PNT performance. The architecture of coupled integration is designed and degraded when any subsystem fails. A mathematical model for a precise time aiding navigation filter is derived rigorously. The CSAC aids positioning by weighted linear optimization when the visible satellite number is four or larger. By contrast, CSAC converts the GNSS observations to range measurements by "clock coasting" when the visible satellite number is less than four, thereby constraining the error divergence of micro inertial navigation and improving the availability of GNSS signals and the positioning accuracy of the integration. Field vehicle experiments, both in open-sky area and in a harsh environment, show that the integration can improve the positioning probability and accuracy.

  12. Discussion of the target-missile control scheme with supersonic speed at minimum altitude

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    An antiship missile with supersonic speed at minimum altitude is an effective weapon to break through a defense line. The former Soviet Union was a leader in this field since it had developed several kinds of antiship missiles which obtained supersonic speed at minimum altitudes. To counter this kind of missile,many countries have been developing corresponding antimissiles. For the purpose of verifing the antimissile missile's effectiveness in intercepting antiship missiles, a target-missile is needed. A target-missle is cheaper and can imitate the main characteristics of antiship missiles with supersonic speed at minimum altitude. In this paper, the control scheme of a target missile flying with supersonic speed at minimum altitude is studied. To counter the problem of hedgehopping over the sea, a control scheme utilizing a SINS + altimeter was proposed.In this scheme, both the quick response ability of altitude control and the anti-jamming problem were considered. A simulation experiment shows that when an integrated altitude control system is used, the anti-disturbance ability of the integrated altitude is good and the response speed of altitude control system can be dramatically improved.

  13. A hierarchical model for structure learning based on the physiological characteristics of neurons

    Institute of Scientific and Technical Information of China (English)

    WEI Hui

    2007-01-01

    Almost all applications of Artificial Neural Networks (ANNs) depend mainly on their memory ability.The characteristics of typical ANN models are fixed connections,with evolved weights,globalized representations,and globalized optimizations,all based on a mathematical approach.This makes those models to be deficient in robustness,efficiency of learning,capacity,anti-jamming between training sets,and correlativity of samples,etc.In this paper,we attempt to address these problems by adopting the characteristics of biological neurons in morphology and signal processing.A hierarchical neural network was designed and realized to implement structure learning and representations based on connected structures.The basic characteristics of this model are localized and random connections,field limitations of neuron fan-in and fan-out,dynamic behavior of neurons,and samples represented through different sub-circuits of neurons specialized into different response patterns.At the end of this paper,some important aspects of error correction,capacity,learning efficiency,and soundness of structural representation are analyzed theoretically.This paper has demonstrated the feasibility and advantages of structure learning and representation.This model can serve as a fundamental element of cognitive systems such as perception and associative memory.Key-words structure learning,representation,associative memory,computational neuroscience

  14. Communication Control of PLC and Inverter Based on Extended Memory%基于扩展存储器的PLC与变频器的通讯控制

    Institute of Scientific and Technical Information of China (English)

    阮友德; 许小华

    2011-01-01

    本文针对PLC与变频器的通讯控制,详细介绍了一种基于FX2N-ROM-E1的通讯控制系统,并且给出了系统的硬件组成和程序梯形图,阐述了PLC的通讯格式和变频器的通讯参数及指令代码.实践证明,系统具有抗干扰能力强、传输速率高、编程简便、造价低廉等特点.%Aiming at communication control of PLC and inverter,this article introduces the communication control system which is based on FX2N-ROM-E1, and gives the hardware's composition and program ladder of the system. also elaborates the communication format of PLC and communication parameters and instruction codes of inverter. Facts have proved that the system is not only possessing powerful anti-jamming capability, high transmission speed, but also simple programming.

  15. 高精度陀螺稳定平台稳定回路设计%Design of Stabilized Loop for High Precision Gyro-stabilized Platform

    Institute of Scientific and Technical Information of China (English)

    王巾; 王凯

    2012-01-01

      The working principle of the two-axis gyro-stabilized platform for isolating the carrier disturbance is introduced. The mathematical model is analyzed and designed for the stabilized loop of the gyro-stabilized plat⁃form. A dual rate-loop control structure is chosen, so the servo system has the better anti-jamming ability and ro⁃bustness than the single rate-loop control structure. The experimental data from the prototype show that this gy⁃ro-stabilized platform has a better stabilized precision.%  介绍了两轴陀螺稳定平台隔离载体扰动的原理,对陀螺稳定平台的稳定回路进行了数学建模分析和设计。选择了双速度环控制方法,使稳定伺服系统较传统的单速度环方法具有更好的抗干扰性和鲁棒性,并通过样机测试数据表明,该稳定平台具有较高的稳定精度

  16. Blocking junctional adhesion molecule C enhances dendritic cell migration and boosts the immune responses against Leishmania major.

    Directory of Open Access Journals (Sweden)

    Romain Ballet

    2014-12-01

    Full Text Available The recruitment of dendritic cells to sites of infections and their migration to lymph nodes is fundamental for antigen processing and presentation to T cells. In the present study, we showed that antibody blockade of junctional adhesion molecule C (JAM-C on endothelial cells removed JAM-C away from junctions and increased vascular permeability after L. major infection. This has multiple consequences on the output of the immune response. In resistant C57BL/6 and susceptible BALB/c mice, we found higher numbers of innate immune cells migrating from blood to the site of infection. The subsequent migration of dendritic cells (DCs from the skin to the draining lymph node was also improved, thereby boosting the induction of the adaptive immune response. In C57BL/6 mice, JAM-C blockade after L. major injection led to an enhanced IFN-γ dominated T helper 1 (Th1 response with reduced skin lesions and parasite burden. Conversely, anti JAM-C treatment increased the IL-4-driven T helper 2 (Th2 response in BALB/c mice with disease exacerbation. Overall, our results show that JAM-C blockade can finely-tune the innate cell migration and accelerate the consequent immune response to L. major without changing the type of the T helper cell response.

  17. Research on the measurement of belt speed by video in coal mine based on improved template matching algorithm

    Institute of Scientific and Technical Information of China (English)

    ZHU Ai-chun; HUA Wei; WANG Chun; WANG Yong-xing

    2011-01-01

    In order to improve the intelligence of video monitoring system of belt and make up the deficiency of higher failure rate and bad real-time performance in the traditional systems of measurement of belt speed,according to the fact that the light of coal mine is uneven,the strength of light changes greatly,the direction of belt movement is constant,and the position of camera was fixed,various algorithms of speed measurement by video were studied,and algorithm for template matching based on sum of absolute differences(SAD)and correlation coefficient was proposed and improved,besides,the tracking of feature regions was realized.Then,a camera calibration method using the invariance of the cross-ratio was adopted and the real-time measurement of belt speed by the hardware platform based on DM642 was realized.Finally,experiment results show that this method not only has advantages of high precision and strong anti-jamming capability but also can real-time reflect the changes of belt speed,so it has a comprehensive applicability.

  18. 高温超导滤波器用斯特林制冷机温度控制算法设计%Design of temperature controlling algorithm for Stirling cryocooler used in high temperature superconducting filters

    Institute of Scientific and Technical Information of China (English)

    魏广; 马少君; 闫春杰

    2012-01-01

    In the domain of deep space communications, using of high temperature superconducting technology can significantly improve the receivers performance in sensitivity, signal noise ratio and anti -jamming. As the need for high temperature superconducting filter's low temperature working environment, a Stirling cryocooler for cooling was required. The stability of Stirling cryocoolers temperature will directly affect the performance of high temperature superconducting filter. This topic mainly focused on the temperature controlling algorithm s analysis and design for Stirling cryocooler used in high temperature superconducting filters, the temperature controlling curve based on tester of high temperature superconducting filters were proved at last.%在深空通信领域,利用高温超导滤波技术,可大幅提高接收机的灵敏度、信噪比和抗干扰能力.由于高温超导滤波器工作温度较低,需要斯特林制冷机进行制冷.斯特林制冷机温度的稳定性将直接影响高温超导滤波器的性能,文章对高温超导滤波器用斯特林制冷机温度控制算法进行了分析和设计,并给出了基于高温超导滤波器试验装置的温度控制曲线.

  19. Fuzzy clustering of infrared images applied in air leak localization

    Science.gov (United States)

    Ge, Nan; Peng, Guang-zheng; Jiang, Mu-zhou

    2009-07-01

    Most current research into the localization of leaks is focused on leaks of petroleum and natural gas pipelines, while there is very little new work being done on the leakage of vessels. A novel air-leak diagnosis and localization method based on infrared thermography is described in this paper, which is developed in an attempt to overcome the disadvantages of low efficiency and poor anti-jamming ability associated with the traditional approaches to localization of leaks from a vessel. The method achieves leak positioning through a factor θ based kernelized fuzzy clustering segmentation done to weighted differential thermal images of the test objects. The temperature difference factor θ is inventively built as a parameter changed with temperature range of the target region, in order to enhance the robustness and the interference proof ability of the algorithm. Heat transfer simulation with air-leak flow is addressed by the finite element analysis. The experimental results indicate that the method proposed is effective and sensitive. The purpose of air-leak localization has been reached.

  20. 红外对抗及其半实物仿真试验研究%Research on Infrared Countermeasure and Hardware-in-the-loop Simulation

    Institute of Scientific and Technical Information of China (English)

    陈敏; 李龙

    2013-01-01

      随着红外探测技术的不断发展,红外干扰与抗干扰技术也不断更新、发展。介绍了红外对抗的原理,方法,着重介绍了模拟红外对抗的红外半实物仿真试验,分析了仿真系统中的关键技术及各种可供选择的场景模拟和运动平台特点,最后提出了一种切实可行的红外半实物仿真试验方案。%  With the development of infrared technology, infrared jamming and anti-jamming technologies are constantly updating and developing. The principle of infrared countermeasure method is introduced, with a particular emphasis on infrared hardware-in-the-loop simulation experiment of IR countermeasure. The scene simulation, the motion platform, and key technical characteristics are analyzed. Finally, a viable infrared hardware-in-the-loop method is presented.

  1. Design of Stress-Strain Measuring System for Bulldozing Plate Based on Virtual Instrument Technology

    International Nuclear Information System (INIS)

    Soil is a kind of discrete, multiphase compound that is composed of soil particles, liquid and air. When soil is disturbed by bulldozing plate, the mechanical behavior of the soil will become very complex. Based on the law of action and reaction, the dynamic mechanical behavior of disturbed soil was indirectly analyzed by measuring and studying the forces on the bulldozing plate by soil currently, so a stress-strain virtual measuring system for bulldozing plate, which was designed by the graphical programming language DASYLab, was used to measure the horizontal force Fz acting on the bulldozing plate. In addition, during the course of design, the experimental complexities and the interferential factors influencing on signal logging were analyzed when bulldozing plate worked, so the anti-jamming methods of hardware and software technology were adopted correlatively. In the end, the horizontal force Fz was analyzed with Error Theory, the result shown that the quantificational analysis of Fz were identical to the qualitative results of soil well, and the error of the whole test system is under 5 percent, so the tress-strain virtual measuring system was stable and credible

  2. Research of satellite interference monitoring technology based on LabVIEW%基于LabVIEW的卫星干扰监测技术研究

    Institute of Scientific and Technical Information of China (English)

    王哨军; 陈天立; 陈鑫

    2011-01-01

    针对卫星干扰特性及抗干扰方式,开发出1套实时监测干扰的系统.系统利用Datasocket技术,能实现对入站干扰的远程监控,实时显示入站波形,对超门限干扰及平均人站功率大幅度跳变进行声光报警,并具有干扰数据的自动存储及复现功能;针对干扰源幅差法定位,可通过远程登陆自动提取入站波束的G/T差值,此系统一定程度上消除了干扰对系统的影响.%Aim at the interference characteristics and anti-jamming mode of satellite signal, this paper designs a set of real-time interference monitoring system. This system makes use of datasocket technology, it can achieve the remote monitoring purpose, with the functions as real-time waveform display, sound and light alarm bringed on by superthreshold interference and the transition of incoming power , it also hold the functions of automatic data storage and interfere redisplay. For the implement of the interference orientation, this program can automatically extracted the G/T difference data by remote login. To some extent ,it eliminate the interference impact on satellite signal

  3. Test results judgment method based on BIT faults

    Institute of Scientific and Technical Information of China (English)

    Wang Gang; Qiu Jing; Liu Guanjun; Lyu Kehong

    2015-01-01

    Built-in-test (BIT) is responsible for equipment fault detection, so the test data correct-ness directly influences diagnosis results. Equipment suffers all kinds of environment stresses, such as temperature, vibration, and electromagnetic stress. As embedded testing facility, BIT also suffers from these stresses and the interferences/faults are caused, so that the test course is influenced, resulting in incredible results. Therefore it is necessary to monitor test data and judge test failures. Stress monitor and BIT self-diagnosis would redound to BIT reliability, but the existing anti-jamming researches are mainly safeguard design and signal process. This paper focuses on test results monitor and BIT equipment (BITE) failure judge, and a series of improved approaches is proposed. Firstly the stress influences on components are illustrated and the effects on the diagnosis results are summarized. Secondly a composite BIT program is proposed with information integra-tion, and a stress monitor program is given. Thirdly, based on the detailed analysis of system faults and forms of BIT results, the test sequence control method is proposed. It assists BITE failure judge and reduces error probability. Finally the validation cases prove that these approaches enhance credibility.

  4. 多模式化数字语音录放显示系统创新设计%lnnovative Design of Multi-mode Digital Voice Recording System

    Institute of Scientific and Technical Information of China (English)

    钱丹浩; 刘萍萍

    2015-01-01

    This paper using STM32 microcontrol er core,designs a multi-mode digital voice recording system,which consti-tuted by the foundation of the recording-platform and the monitoring-module,and a digital-voice recording system of the Multi-mode,and givens its hardware circuit and discusses the course of their work.Designing the program's main work pro-cesses and algorithms,the system is simple,good anti-jamming.%以STM32微控制器为核心,设计出由基础录放平台和功能测控模块构成的多模式化数字语音录放和显示系统,给出了其硬件电路并论述其工作过程,设计了程序的主要工作流程和算法。该系统结构简单,抗干扰性好。

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

    Directory of Open Access Journals (Sweden)

    Yi-Xiong Zhang

    2016-06-01

    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.

  6. High Speed Dim Air Target Detection Using Airborne Radar under Clutter and Jamming Effects

    Directory of Open Access Journals (Sweden)

    A. E. Almslmany

    2015-06-01

    Full Text Available The challenging potential problems associated with using airborne radar in detection of high Speed Maneuvering Dim Target (HSMDT are the highly noise, jamming and clutter effects. The problem is not only how to remove clutter and jamming as well as the range migration and Doppler ambiguity estimation problems due to high relative speed between the targets and airborne radar. Some of the recently published works ignored the range migration problems, while the others ignored the Doppler ambiguity estimation. In this paper a new hybrid technique using Optimum Space Time Adaptive Processing (OSTAP, Second Order Keystone Transform (SOKT, and the Improved Fractional Radon Transform (IFrRT was proposed. The OSTAP was applied as anti-jamming and clutter rejection method, the SOKT corrects the range curvature and part of the range walk, then the IFrRT estimates the target’ radial acceleration and corrects the residual range walk. The simulation demonstrates the validity and effectiveness of the proposed technique, and its advantages over the previous researches by comparing its probability of detection with the traditional methods. The new approach increases the probability of detection, and also overcomes the limitation of Doppler frequency ambiguity.

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

    Science.gov (United States)

    Zhang, Yi-Xiong; Liu, Qi-Fan; Hong, Ru-Jia; Pan, Ping-Ping; Deng, Zhen-Miao

    2016-01-01

    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. PMID:27271629

  8. Software Implement of Resolver-to-Digital Converter Based on AD7655%基于AD7655的旋转变压器-数字转换器的软件实现

    Institute of Scientific and Technical Information of China (English)

    何文静; 胥效文; 史忠科

    2013-01-01

    设计了一种基于片外高速16位A/D的旋转变压器-数字转换器.给出了系统各模块的设计思想和软件设计流程,完成了4极对旋转变压器的驱动和输出信号的调理、采样、解算、上传及存储,并对系统误差进行了分析.实验测试表明,系统具有结构简单、分辨率高、抗干扰性好、灵活性强等优点.%A resolver-to-digital converter based on high-speed 16 bit A/D is proposed. The system design concept and software design process are presented. The driver module and signal conditioning, acquisition, calculating, storage and uploading of the 4-pole resolver are completed as well. Meanwhile, the error of the system is discussed. The results show that the system achieves simple structure, high resolution, good anti-jamming performance and flexibility.

  9. 随钻测量系统设计%Design of a measurement-while-drilling system

    Institute of Scientific and Technical Information of China (English)

    詹世玉

    2011-01-01

    According to MWD equipment needs growing, based on analyzing MWD system works,the paper designed a MWD system ,which consists of three-axis accelerometer,three-axis and three-axis gyroscope. On the control core of DSP, a advanced MENS chip and some anti-jamming, error correction and temperature compensation measures of improve performance are adopted for design.The results show that the system has high accuracy, good stability, strong ability to adapt.%针对随钻测量设备需求日益增大,本文在分析随钻测量系统工作原理的基础上,设计一套由三轴加速度计、三轴磁阻传感器与三轴陀螺仪组成的随钻测量系统.以DSP为控制核心,采用先进的MEMS芯片,同时采取相应的抗干扰、误差修正、温度补偿等改善性能措施.结果表明,系统具有测量精度高、稳定性好、适应能力强等优点.

  10. 基于CAN的多通道数据采集系统的设计%Design of a Multi-Channel Data Acquisition System Based on CAN

    Institute of Scientific and Technical Information of China (English)

    赵海生; 胥效文

    2012-01-01

    提出了一种基于CAN总线,应用于航空发动机动态测试的多通道数据采集系统的设计方案.完成了对各传感器输出信号及电源信号的调理、采集、分析处理及上传,并对系统进行了非线性误差标定.给出了数据采集系统各模块的设计思想及系统软件设计流程.试验结果表明,该多通道数据采集系统具有抗干扰性强、采集精度高、接口灵活等优点,满足该型航空发动机测试系统的需求.%A CAN bus-based multi-channel data acquisition system applied in aero-engine dynamic test is proposed. Signal conditioning, acquisition, analysis, process and upload of various sensors signal and powers signal are completed in system design. Meanwhile system nonlinear error calibration is done. Detailed module design concept and software design process are presented also. The results show that the proposed multi-channel data acquisition system achieves good anti-jamming performance, high accuracy, flexible interface, and satisfies the requirements of aero-engine dynamic test.

  11. Convolutive Frequency-Domain Blind Interference-Signal Separation Algorithm Based on IVA%基于IVA的卷积混合频域盲扰信分离算法研究

    Institute of Scientific and Technical Information of China (English)

    文威; 张杭

    2012-01-01

    Blind interference-signal separation technique is the application of Blind Source Separation (BSS) in anti-jamming. This paper introduced a frequency-domain convolutive blind interference-signal separation algorithm based on Independent Vector Analysis (IVA), which prevents permutation ambiguity and acquires better separation performance. Simulation results indicate that this algorithm can separate BPSK signal and a variety of interference, and has cer- tain anti-interference ability.%盲扰信分离是盲源分离算法在无线通信抗干扰中的应用。文章将独立向量分析(IVA)引入到卷积混合频域盲扰信分离算法中,克服了频域方法存在顺序不确定性和分离效果不佳的缺陷。仿真实验表明该算法的有效性,采用该算法实现了卷积混合条件下BPSK信号与多种干扰的扰信分离,具有一定的抗干扰能力。

  12. CCD video information acquisition technology based on image pattern%基于图象模式的CCD视频信息采集技术

    Institute of Scientific and Technical Information of China (English)

    王汉兵; 黄涛; 雷磊; 周永平; 陈世纯

    2011-01-01

    以某型反坦克导弹CCD观测器测试系统的研制为背景,结合典型CCD观测器的性能及工作原理,对观测器的核心输出信号即视频信息的提取及关键软硬件设计进行了较为深入的研究,运用数字处理和视频采集技术,给出测角精度、抗干扰能力和灵敏度的分析处理方法.系统技术先进,操作界面友好,分析直观,工作可靠,很好地满足使用要求.%This study is one department of CCD observer test system development for a certain type of anti -tank missile. According to the performance and working principle of typical CCD observer, the authors deeply researched the extraction of core output signals, namely video information, and the key software and hardware design of observer. A method for processing and analyzing angle measurement accuracy, anti -jamming capability and sensitivity was provided through digital processing and video capture technology. Such system commendably satisfies the requirements for application with advanced technology, user-friendly interface, intiutive analysis and reliable function.

  13. Coupled Integration of CSAC, MIMU, and GNSS for Improved PNT Performance.

    Science.gov (United States)

    Ma, Lin; You, Zheng; Liu, Tianyi; Shi, Shuai

    2016-01-01

    Positioning, navigation, and timing (PNT) is a strategic key technology widely used in military and civilian applications. Global navigation satellite systems (GNSS) are the most important PNT techniques. However, the vulnerability of GNSS threatens PNT service quality, and integrations with other information are necessary. A chip scale atomic clock (CSAC) provides high-precision frequency and high-accuracy time information in a short time. A micro inertial measurement unit (MIMU) provides a strap-down inertial navigation system (SINS) with rich navigation information, better real-time feed, anti-jamming, and error accumulation. This study explores the coupled integration of CSAC, MIMU, and GNSS to enhance PNT performance. The architecture of coupled integration is designed and degraded when any subsystem fails. A mathematical model for a precise time aiding navigation filter is derived rigorously. The CSAC aids positioning by weighted linear optimization when the visible satellite number is four or larger. By contrast, CSAC converts the GNSS observations to range measurements by "clock coasting" when the visible satellite number is less than four, thereby constraining the error divergence of micro inertial navigation and improving the availability of GNSS signals and the positioning accuracy of the integration. Field vehicle experiments, both in open-sky area and in a harsh environment, show that the integration can improve the positioning probability and accuracy. PMID:27187399

  14. 智能插座在高校节能减排工程中的设计和应用%The Design and Application of Intelligent Electrical Outlet for Campus ’s Electricity Saving and Emission Reduction

    Institute of Scientific and Technical Information of China (English)

    马艳

    2013-01-01

    高校用电浪费现象十分突出,本文研究的智能插座能有效计量和控制供电线路,通过控制不必要时段的电器电源供电,达到节能减排的目的,且智能插座还具有安全、可靠、防电磁辐射和抗干扰等优点。%The electrical energy waste phenomenon on colleges and universities’campuses is very severe. This paper introduces the design and application of intelligent electrical outlet, which can measure effectively electricity data and control power supply line on-off, cut off electrical appliance ’s power at nonessential time interval, thus achieves the goal of electricity saving and emission reduction. This intelligent outlet is also safe, reliable, anti-electromagnetic radiation and anti-jamming.

  15. 基于FPGA的数字心率监测仪设计%Design of Digital Heart Rate Monitor Based on FPGA

    Institute of Scientific and Technical Information of China (English)

    徐宏祥; 田丰; 刘国权; 于东阳; 曹祎

    2011-01-01

    This paper introduces a method to design a digital heart rate monitor based on field - programmable gate array (FPGA). The electrical signal of pulse is collected by the pulse transducer, after the pre - processing and A/D conversion, the signal is given to the FPGA for data storage and processing. The monitor has the functions of real - time monitoring and displaying the heart rate parameters, automatic alarm. The system has advantages in anti -jamming and integration with easy expansion.%提出了一种基于现场可编程门阵列( FPGA)的数字心率监测仪的设计方案.由脉搏传感器采集到的脉搏信号经过预处理和模/数转换,送给FPGA进行数据存储及处理,实现实时监测与显示心率参数、自动报警等功能,具有抗干扰性好、集成度高和易于扩展的优点.

  16. Multifunction Capacitive Sensor Measuring System Based on USB%USB接口的多功能容栅传感器测量系统

    Institute of Scientific and Technical Information of China (English)

    李孝超; 严高师

    2011-01-01

    According to the principle of capacitive sensors and the C8052F321 MCU with USB module,a measurement system based on USB interface is designed. The system can track the maximum and the minimum counting, hold the display and clear, and uses USB interface to exchange data with the host computer. The system uses LM393 chip to convert the signal level of the sensor to the CMOS level,and also uses opto isolation technology to enhance system's anti-jamming capability.%根据容栅传感器的原理与带USB模块的C8051F321单片机,设计了一套基于USB接口的测量系统。该系统能实现最大数跟踪、最小数跟踪、示值保持和清零等功能,通过USB接口与上位机交换数据。系统中采用LM393芯片将传感器信号电平转换为CMOS电平,采用光耦隔离技术等增强系统的抗干扰能力。

  17. Multifunction Displacement Measurement System Based on Short-range Wireless Technology%基于短距离无线技术的多功能位移测量系统

    Institute of Scientific and Technical Information of China (English)

    李孝超; 严高师

    2012-01-01

    根据容栅传感器的原理和具有高灵敏度的A7102射频芯片加低功耗的STM8L101F3单片机,设计了一套多功能无线位移测量系统.该系统能实现最大数跟踪、最小数跟踪、示值保持和清零等功能.系统中采用专用芯片将传感器信号电平转换为CMOS电平,还采用光耦隔离技术等增强系统的抗干扰能力.%According to the principle of capacitive sensors and the A7102 RF chip with a high sensitivity and the STM8L101F3 MCU with low-power consumption,this paper designed a multifunction wireless measurement system. This system can track the maximum and the minimum, keep count and clear. The system used a special chip to convert the signal level of the sensor to the CMOS level, and it used opto isolation technology to enhance the system's anti-jamming capability.

  18. 智能控制策略在屠宰场废水处理中的应用%Application of Intelligent Control Strategy in Slaughterhouse Wastewater Treatment

    Institute of Scientific and Technical Information of China (English)

    毕建朝; 杨志

    2011-01-01

    Taking into consideration the difficulties in realizing optimization of slaughterhouse wastewater treatment with the traditional control strategies,the authors of this paper have designed an intelligent controller.The paper analyzes the characteristics of the process,constructs a control model,discusses the control algorithm and makes a simulation comparison research on the designed control algorithm and the optimal PID control algorithm under MATLAB environment.The results show that the algorithm is satisfactory in anti-jamming performance and in robustness and verify its reasonability and feasibility.It is concluded that this intelligent controller can effectively ensure the quality of the output water.%针对传统控制策略在屠宰场废水处理过程中难以实现优化控制而设计了一种智能控制器.分析了过程特性,建立了控制模型,讨论了控制算法,在MATLAB环境下对所设计的控制算法与最优PID控制算法作了仿真比较研究.结果表明:该算法抗干扰性较好和鲁棒性强,验证了其合理性和可行性,可有效保证屠宰场废水处理的出水水质.

  19. Status and Development Trend of the Military GPS Receiver%军用卫星导航接收机现状及发展趋势

    Institute of Scientific and Technical Information of China (English)

    任小伟

    2014-01-01

    本文总结了GPS接收机在军事应用上的优点及不足,并探讨了军用卫星导航接收机技术的发展趋势。详细介绍了多模卫星导航接收机系统的兼容与互用技术、抗干扰滤波技术、环路滤波技术、组合导航技术、以及相对定位技术,并对相关卫星导航接收机新技术进行了总结和展望。%The advantages and disadvantages of GPS receivers on the military application are summarized and the development trend of military satellite navigation technology is discussed in this paper. Compatibility and interoperability technology, anti-jamming filter technology, loop filter technology, integrated navigation technology, and relative positioning technology of multimode satellite system are introduced. Finally, the new technology of the correlative satellite navigation is summarized and prospected.

  20. [Study on polarization spectral feature of suspended sediment in the water body].

    Science.gov (United States)

    Zhu, Jin; Wang, Xian-Hua; Pan, Bang-Long

    2012-07-01

    Remote sensing of lake water based on water-leaving radiance is to retrieve the concentrations of suspended sediment, phytoplankton and yellow substance which have great impacts on spectrum to assess the water quality. Howerver, because of the complexity of the lake water compositons and the interference between the different components, it is of great difficulty to get accurate results with the reflectance spectrum method developed recently. In the present paper, the authors firstly discussed the reflectance and polarization spectral feature of suspended sediment water body, found out the relations of the reflectance and the degree of polarization of water-leaving radiance and the concentration of suspended sediment at the sensitive bands. The authors also compared the effectiveness of the retrieval approaches based on reflectance and polarization in laboratory water body and Chaohu water body respectively. The results show that in the lake water body where the constituents are very complex, the polarization information has greater capacity of anti-jamming, therefore it will have great potential applictions in lake water quality remote sensing. PMID:23016352

  1. 10kV配电站电气系统设计%Design on Electrical System of 10 kV Substation

    Institute of Scientific and Technical Information of China (English)

    韩朝辉

    2012-01-01

    针对10 kV配电站中的电气系统进行了详细的分析设计,首先简要分析了配电站开关站的布置方式,在此基础上对配电站电气系统进行了分析设计,给出了一次电气系统设计布置方案,并就其中一些关键性技术问题展开了探讨,最后分析了电气系统抗干扰措施的应用。%The electrical system of 10 kV substation is analyzed and designed in detail in this paper,firstly,the switching station layout of the distribution station is discussed,on the basis of which,the electrical system of distribution station is analyzed and designed of the system,the layout of the electrical system design programs is pointed out,and some key technical issues are also discussed,and finally the application of anti-jamming measures for the electrical system is analyzed.

  2. Identifying opinion leaders by improved algorithm based on Leader- Rank%改进LeaderRank算法的意见领袖挖掘

    Institute of Scientific and Technical Information of China (English)

    徐郡明; 朱福喜; 刘世超; 朱碧颖

    2015-01-01

    Opinion leader mining is an important topic of social network research which is of great significance in terms of internet public opinion control and information dissemination. LeaderRank is an effective opinion leader mining algorithm. This paper proposes a new algorithm based on LeaderRank with sentiment analysis and user’s liveness to identify the opinion leaders in comment network to achieve a better performance. Experiments based on SIR model show that both accuracy and anti-jamming capability of the proposed algorithm have been effectively improved.%意见领袖挖掘是社会网络研究的重要课题,对于舆情控制、信息传播等方面具有重要意义。LeaderRank算法是一个有效的意见领袖挖掘算法。为提高LeaderRank算法的准确性和抗干扰能力,在LeaderRank算法基础上,加入用户之间的情感倾向、用户活跃程度,提出了改进的LeaderRank算法。基于SIR模型的实验验证表明,改进算法的准确性和抗干扰能力均得到了有效提升。

  3. Monitoring technique for seepage line of tailings dam

    Institute of Scientific and Technical Information of China (English)

    李夕兵; 蒋卫东

    2003-01-01

    An automatic monitoring technique of the seepage line, including the monitoring design, the automatic monitoring system and the backfill technique of the measuring probe of pore-water pressure, was used in a tailings dam, and a shallow refractive seismic method was investigated for obtaining the seepage line of those areas outside the monitoring zone. The results show that the automatic monitoring has the error within ± 3 % relative to piezometric tube method and improves monitoring efficiency greatly, and the shallow refractive seismic method has the error within ± 10% but expands the area of monitoring. Both of them can be used for a daily measurement in monitoring the seepage line. The result of the automatic monitoring also shows that not only the design of the survey line and the backfill technique of the measuring probe of pore-water pressure are reasonable and economic but also the reliability and safety of the automatic monitoring system are better. Testing result by the shallow refractive seismic method in tailings reveals that the energy excited by hammering iron sheet-pole is strong enough and safe, and that the character of anti-jamming by the detectors with long tailcone is better.

  4. Gear Box State Detection System Based on Fiber Grating Sensor%基于光纤光栅传感器的齿轮箱状态监测系统

    Institute of Scientific and Technical Information of China (English)

    陈亮; 王其林; 李旭松

    2011-01-01

    It is hard to measure gear abrasion of certain type artillery collimator gear box. Therefore design a real time detection system of gear box. The system hardware uses fiber grating sensor as measuring node and adopts fiber as signal transmission medium. The signal is inputted into virtual instrument platform through demodulation system and carried out data processing and displaying. The system software functions include fiber grating demodulation, oscillation signal revivification and gear state estimation. Characteristic of the system is anti-jamming, anti-erosion, small type and easy to integrating.%针对某舰舰炮瞄准机齿轮箱齿轮磨损程度不易测量的问题,设计一种齿轮箱状态实时监测系统.系统硬件以光纤光栅传感器为测量节点,光纤为信号传输介质,信号经解调系统输入虚拟仪器平台,进行数据处理与显示.系统软件功能包括光纤光栅解调、箱体振动信号还原和齿轮状态评估.该系统具有抗干扰、抗腐蚀性强,体积小巧,便于管理,易于集成的特点.

  5. A novel cognitive ISAR imaging method with random stepped frequency chirp signal

    Institute of Scientific and Technical Information of China (English)

    ZHU Feng; ZHANG Qun; LUO Ying; LI KaiMing; GU FuFei

    2012-01-01

    The random stepped frequency chirp signal (RSFCS) has better performance in anti-jamming than that of conventional stepped frequency chirp signal (SFCS).In combination with the theory of compressing sensing (CS),a novel ISAR imaging method is proposed based on RSFCS,in which the high resolution range profile (HRRP) is reconstructed by using the conventional OMP algorithm,whereas the cognitive approach is introduced to further reduce the number of sub-pulse in RSFCS.In the proposed method,via cognizing the characteristics of moving targets,the number of sub-pulse in each burst can be adjusted adaptively.Finally,in the cross-range direction,the accurate reconstruction of ISAR image by using CS theory is implemented,which can effectively accomplish unwrapping.With the proposed method,high quality HRRP and ISAR image can be achieved with fewer sub-pulses of RSFCS and lower burst repetition frequency (BRF).Some simulation results are given to validate the effectiveness and robustness of the proposed algorithm.

  6. A Unified Multi-Functional Dynamic Spectrum Access Framework: Tutorial, Theory and Multi-GHz Wideband Testbed

    Directory of Open Access Journals (Sweden)

    Zhe Chen

    2009-08-01

    Full Text Available Dynamic spectrum access is a must-have ingredient for future sensors that are ideally cognitive. The goal of this paper is a tutorial treatment of wideband cognitive radio and radar—a convergence of (1 algorithms survey, (2 hardware platforms survey, (3 challenges for multi-function (radar/communications multi-GHz front end, (4 compressed sensing for multi-GHz waveforms—revolutionary A/D, (5 machine learning for cognitive radio/radar, (6 quickest detection, and (7 overlay/underlay cognitive radio waveforms. One focus of this paper is to address the multi-GHz front end, which is the challenge for the next-generation cognitive sensors. The unifying theme of this paper is to spell out the convergence for cognitive radio, radar, and anti-jamming. Moore’s law drives the system functions into digital parts.From a system viewpoint, this paper gives the first comprehensive treatment for the functions and the challenges of this multi-function (wideband system. This paper brings together the inter-disciplinary knowledge.

  7. Research progress in SAW filter banks

    Institute of Scientific and Technical Information of China (English)

    HE Shi-tang

    2005-01-01

    SAW (Surface Acoustic Wave) filter bank is a single input, single or multi-output device consisting of multi-SAW-filters with input interconnection network or switch circuits, and can be divided into two categories: channelizer (multi-output) and switchable (programmable, single output). The former is mainly used in military channelized receiver for spectrum analysis;the latter has wide application in frequency synthesizer and frequency-hopping radar and communication system receiver as anti-jamming filter, and has been widely used in various military electronic equipments ever since the 1970s.Research abroad was done mainly by Americans, few documents on related work done by Japan and Russia are available. Domestic research started in the 1980s, mainly by No. 26 Research Institute, China Electronics Technology Group Co., Institute of Acoustics, Chinese Academy of Sciences, No. 23 and No. 25 Research Institute, China Spaceflight Tech. Group Co. This paper first briefly introduces Chinese and foreign research on SAW filter banks;then discusses research progress in device design, the input interconnection network or switch circuit and miniaturization;and ends in a brief perspective of developing trends in future.

  8. Carrier Sense Random Packet CDMA Protocol in Dual-Channel Networks

    Directory of Open Access Journals (Sweden)

    C. Du

    2015-06-01

    Full Text Available Code resource wastage is caused by the reason that many hopping frequency (FH sequences are unused, which occurs under the condition that the number of the actual subnets needed for the tactical network is far smaller than the networking capacity of code division net¬working. Dual-channel network (DCN, consisting of one single control channel and multiple data channels, can solve the code resource wastage effectively. To improve the anti-jamming capability of the control channel of DCN, code division multiple access (CDMA technology was introduced, and a carrier sense random packet (CSRP CDMA protocol based on random packet CDMA (RP-CDMA was proposed. In CSRP-CDMA, we provide a carrier sensing random packet mechanism and a packet-segment acknowledgement policy. Furthermore, an analytical model was developed to evaluate the performance of CSRP-CDMA networks. In this model, the impacts of multi-access interference from both inter-clusters and intra-clusters were analyzed, and the mathematical expressions of packet transmission success probability, normalized network throughput and signal interference to noise ratio, were also derived. Analytical and simulation results demonstrate that the normalized network throughput of CSRP-CDMA outperforms traditional RP-CDMA by 10%, which can guarantee the resource utilization efficiency of the control channel in DCNs.

  9. Bistatic weak target detection method using non-cooperative air surveillance radar

    Institute of Scientific and Technical Information of China (English)

    Zengping Chen

    2015-01-01

    At present, most of the passive radar system re-searches utilize FM radios, TV broadcasts, navigation satel ites, etc. as il uminators. The transmitted signals are not specifical y de-signed radar waveforms. In this work, the frequency agile, phased array air surveil ance radar (ASR) is used as the il uminator of opportunity to detect the weak target. The phased array tech-nology can help realize beam agility to track targets from diffe-rent aspects simultaneously. The frequency agility technology is widely employed in radar system design to increase the ability of anti-jamming and increase the detection probability. While the fre-quency bandwidth of radar signals is usual y wide and the range resolution is high, the range cel migration effect is obvious during the long time integration of non-cooperative bistatic radar. In this context, coherent integration methods are not applicable. In this work, a parametric non-coherent integration algorithm based on task de-interweaving is proposed. Numerical experiments verify that this is effective in weak target detection.

  10. Electromagnetic Compatibility about Backpack Type Inverter & Motor Structure%背包式变频器与电机集成结构的电磁兼容探讨

    Institute of Scientific and Technical Information of China (English)

    秦立新; 刘洋

    2012-01-01

    变频器与电机的集成结构——背包式的电磁兼容问题是个技术问题.由于采用了背包式结构,变频器和电机型式试验将作为一台电机整体来进行考核.变频器的使用,提高了电机系统效率,但是,变频器背包却带来了较为复杂的电磁兼容问题.介绍了背包式变频器+电机的原理和结构,分析了此结构的电磁兼容问题,并提出了系统抗干扰的实际办法.%In the integration structure of the inverter and motor, the electromagnetic compatibility of backpack type is a technical problem. Because of the backpack type structure, type test assessment of motor & inverter will be as a motor overall. Backpack type inverter improves the efficiency of motor system, but brings complex electromagnetic compatibility problems . The principle and structure about backpack type inverter & motor was introduced, the electromagnetic compatibility problems was analyzed, and practical measures of anti-jamming system was put forward.

  11. Study of a control strategy for grid side converter in doubly- fed wind power system

    Science.gov (United States)

    Zhu, D. J.; Tan, Z. L.; Yuan, F.; Wang, Q. Y.; Ding, M.

    2016-08-01

    The grid side converter is an important part of the excitation system of doubly-fed asynchronous generator used in wind power system. As a three-phase voltage source PWM converter, it can not only transfer slip power in the form of active power, but also adjust the reactive power of the grid. This paper proposed a control approach for improving its performance. In this control approach, the dc voltage is regulated by a sliding mode variable structure control scheme and current by a variable structure controller based on the input output linearization. The theoretical bases of the sliding mode variable structure control were introduced, and the stability proof was presented. Switching function of the system has been deduced, sliding mode voltage controller model has been established, and the output of the outer voltage loop is the instruction of the inner current loop. Affine nonlinear model of two input two output equations on d-q axis for current has been established its meeting conditions of exact linearization were proved. In order to improve the anti-jamming capability of the system, a variable structure control was added in the current controller, the control law was deduced. The dual-loop control with sliding mode control in outer voltage loop and linearization variable structure control in inner current loop was proposed. Simulation results demonstrate the effectiveness of the proposed control strategy even during the dc reference voltage and system load variation.

  12. 基于FPGA的扩频信号发生器的研究与设计%Study and Design of Spread-Spectrum Signal Generator Based on FPGA

    Institute of Scientific and Technical Information of China (English)

    王茂林; 杨合圣

    2012-01-01

    扩频通信技术具有抗干扰,抗多径,保密性好,不易被截获以及可以实现码分多址等优点。信号发生器是一种十分重要的仪器,在通信、测控、导航、雷达、医疗等领域有着广泛的应用。文章以直接频率合成和伪随机码的设计与实现为中心,对扩频通信的基本理论,载波调制等问题进行分析与研究。%Spread-spectrum communication has many advantages such as anti-jamming,anti-multipath,confidentiality,difficult to be intercepted,code division and multiple access,and so on.Signal generator is so important a device that it is applied to communication,monitoring and control,navigation,radar,medical and other abroad fields.In this paper,the design and achievement of direct digital frequency synthesize and pseudo-random code is central work,with basic theory of spread-spectrum communication and carrier modulation analyzed and studied.

  13. A Real Orthogonal Space-Time Coded UWB Scheme for Wireless Secure Communications

    Directory of Open Access Journals (Sweden)

    Zhang Yanbing

    2009-01-01

    Full Text Available Recent research reveals that information security and information-hiding capabilities can be enhanced by proper exploitation of space-time techniques. Meanwhile, intrinsic properties of ultra-wideband (UWB signals make it an outstanding candidate for secure applications. In this paper, we propose a space-time coding scheme for impulse radio UWB systems. A novel real orthogonal group code is designed for multi-antenna UWB signals to exploit the full spatial diversity gain and achieve the perfect communication secrecy. Its performance in a frequency-selective fading channel is analyzed. The transmission secrecy, including low probability of detection (LPD, low probability of intercept (LPI, and anti-jamming performance, is investigated, and some fundamental tradeoffs between these secrecy metrics are also addressed. A comparison of the proposed scheme with the direct sequence spread spectrum (DSSS technique is carried out, which demonstrates that proper combination of UWB and space-time coding can provide substantial enhancement to wireless secure communications over other concurrent systems.

  14. 海底光缆安全研究%Study on security in submarine optical fiber cable

    Institute of Scientific and Technical Information of China (English)

    陈利明; 邵芳; 邵平

    2009-01-01

    It has dominated in international communication for submarine optical fiber cable because its large-capacity,reliability and stabilization in quality of service(QoS),high-eonfidentiality, outstanding ability in anti-destruction and anti-jamming and so on.This paper firstly introduced the composing of submarine optical fiber cable system,and then analyzed mostly ingredient that influences its security in transmission line and in-formation.Finally we brought forward some protective measures such as optical fiber cable quality and con-struction, fault positioning and eliminating, enhancing transmission information security and so on.%海底光缆通信具有大容量、通信质量稳定可靠,隐蔽性好,抗毁、抗干扰能力强等特点,成为现代洲际通信的主力.从介绍海底光缆通信系统的组成入手,分析了影响海底光缆传输线路安全和光缆所传输信息安全的主要因素,提出了光缆质量与施工、故障定位与排除和加强信息传输安全等防护措施.

  15. 基于RFID的冷库管理信息系统%RFID -based Management Information System for Cold Storage

    Institute of Scientific and Technical Information of China (English)

    张庆英; 何宁英

    2011-01-01

    As an advanced technique of automatic identification, radio frequency identification ( RFID) has many ad vantages, such as excellent adaptability, high abilities of anti -jamming, high read convenience of hig amount data. The RFID was applied in the cold storage management and a cold storage management information system was designed on the ASP. NET platform. The level of automation of cold storage inventory management was improved and the accuracy and efficiency of cold storage were enhanced.%无线射频识别技术(radio frequency identification,RFID)作为一种自动识别技术的高级形式,具有适应环境能力强、抗干扰强、读取方便和读取数量大等诸多优点.将RFID核心技术应用于冷库的库存管理中,在ASP.NET网络平台上开发了冷库管理信息系统,以提高冷库库存管理各环节的自动化水平和冷库的效率.

  16. Analysis of Electronic Jamming about Ultrashort Wave Communication%一种超短波通信的电子干扰分析方法

    Institute of Scientific and Technical Information of China (English)

    张茜; 刘光斌

    2011-01-01

    To ensure the communication quality of the ultrashort wave radio in the complex electromagnetic environment, aiming at the radio propagation mode of the ultra-shortwave tactical radio, the receiving power in the diverse geological conditions is discussed when the antenna is vertical and horizontal respectively. The jamming ability of the electronic war airplane is compared with the different polarizations adopted. The result shows that the anti-jamming ability is enhanced with the antenna supported lowly used when the electrical parameter round the receiving antenna is biggish.%为确保超短波电台在复杂电磁环境下的通信质量,针对超短波战术电台的电波传播方式,讨论了直立天线和低架水平天线在不同地质条件下的接收功率,比较了敌电子战飞机采用两种极化方式时的干扰能力;当接收天线附近地质的电参数较大时,采用低架水平天线接收方式可以大大提高超短波电台抗敌电子干扰的能力.

  17. Study on interception technique to airborne LPI radar with high probability%对机载LPI雷达的高概率截获技术研究

    Institute of Scientific and Technical Information of China (English)

    邹顺; 胡元奎; 张海黎

    2011-01-01

    The anti-reconnaissance ability and anti-jamming ability of airborne radars can be improved greatly through flexible beam control technique and advanced waveform design technique.A kind of reconnaissance method is put for ward by comprehensively using reconnaissance technique based on digital array,channelized detecting technique based on poly-phase filtering and signal sorting technique based on fuzzy clustering,and the method is hopeful to intercept airborne LPI radar with high probability.%采用先进的功率管理技术和灵活的波形设计技术,能大大提高机载雷达的反侦察和抗干扰能力。提出了一种综合利用数字阵列侦察技术、基于多相滤波的信道化检测技术以及基于模糊聚类的信号分选技术的侦察截获方法,有望实现对机载LPI雷达的高概率截获。

  18. ECCM Effectiveness Measure for SAR Noise Jamming%SAR有源压制干扰抑制效果评估方法研究

    Institute of Scientific and Technical Information of China (English)

    于春锐; 张永胜; 董臻; 梁甸农

    2012-01-01

    合成孔径雷达(SAR)是对地观测和军事侦察的重要手段,但SAR非常容易受电子干扰的影响.SAR干扰技术的发展也促进了抗干扰技术的发展,现代SAR系统往往采用多种抗干扰技术.干扰抑制效果的评估是衡量一种抗干扰方法有效性以及SAR系统抗干扰性能的一项综合性指标.本文针对有源压制干扰,将干扰抑制效果评估方法划分为主观评估方法和客观评估方法.对于主观评估方法,引入了图像质量等级改善因子的概念,提出了基于图像质量等级评估标准的主观评估法,该方法可以在一定程度上降低主观评估结果的随机性和主观性.对于客观评估方法,研究了基于回波能量的评估方法和基于图像质量指标的评估方法,给出了具体的评价指标,可以客观、定量的对干扰抑制效果进行评估.最后分别采用点目标和面目标对客观评估方法进行了仿真验证,结果表明了方法的可行性和有效性.%Synthetic aperture radar ( SAR) plays an important role in earth observation and military reconnaissance fields, but the SAR systems are susceptible to electronic counter measures (ECM). The development of SAR ECM also promoted the SAR electronic counter-countermeasures(ECCM) , generally, modern SAR systems typically can use a variety of antijamming technology. ECCM effectiveness measure is a method to verify the effectiveness of an anti-jamming technology as well as to measure the anti-jamming performance of the SAR system. In this paper,the methods for ECCM effectiveness measure were divided into subjective evaluation methods and objective evaluation methods. For the subjective evaluation, the improvement factor of image quality grade was introduced, and an image quality grade evaluation criteria based method was proposed, which could be subjective to reduce the randomness and subjectivity. For the objective evaluation, the methods based on echo and based on image quality index

  19. 促凝剂对乙型肝炎病毒实时荧光定量检测影响的评估%Assessment of coagulant on hepatitis B virus by real-time fluorescent quantitative detection*

    Institute of Scientific and Technical Information of China (English)

    姜立茹; 马莹

    2013-01-01

    目的评估促凝剂对乙型肝炎病毒实时荧光定量检测的影响。方法随机采集2011年10月至2012年3月到西安市中心医院门诊的41例患者每人2管血样,分别为无添加剂普通管和促凝剂管,检测分离血清时间及效果。采用实时荧光定量聚合酶链反应检测乙型肝炎病毒DNA ,结果对数值采用SPSS11.5统计软件进行处理,并对促凝剂管标本进行精密度和抗干扰性能评价。结果促凝剂管分离血清平均时间为(4.73±0.86)min ,普通管为(14.46±2.27)min ,两组数据经配对 t检验,差异有统计学意义(P<0.01);促凝剂管乙型肝炎病毒DNA结果对数平均值为(3.86±2.99),普通管组对数平均值为(3.85±2.96),两组经配对 t检验,差异无统计学意义(P>0.05),促凝剂管具有高精密度和抗干扰性能。结论促凝剂对乙型肝炎病毒实时荧光定量检测结果准确性没有影响,可减少报告周转时间,值得临床推广和应用。%Objective To evaluate effect of the coagulant on hepatitis B virus by real-time fluorescent quantita-tive detection .Methods From October 2011 to March 2012 were randomly collected in Xi'an city central hospital of 41 patients with each of 2 tubes of blood samples .which were without additives common tube and the coagulant tube . To detected the serum separation time and effect ,using real-time fluorescence quantitative PCR for detection of hepa-titis B virus DNA ,logarithmic mean was performed by SPSS11 .5 statistical analysis ,and the coagulant tube speci-mens for precision and anti-jamming performance evaluation .Results Coagulant group separation of serum average time was (4 .73 ± 0 .86)min ,common tube group was (14 .46 ± 2 .27)min ,data from the two groups were paired t test ,the difference was statistically significant (P0 .05) .coagulant tube had the advantages of high precision and anti-jamming performance .Conclusion

  20. A low-temperature bridge-input CMOS circuit for low-impedance detector

    Science.gov (United States)

    Yuan, HongHui; Chen, YongPing

    2014-09-01

    Low-impedance long-wave infrared detectors (the wavelength longer than 10 microns) have very important applications in cryogenic aim detection, super-distance detection, anti-jamming target identify and so on. Therefore the research in the field of infrared detector technology is of importance. At present, no low-impedance photoconductive detectors are integrated with CMOS circuit. To design low-temperature CMOS circuit being fit for low impedance infrared photoconductive detector and realize high performance IR imaging, using differential amplifier with symmetrical positive and negative power is necessary, the low-resist detector is connected between an input and grounding, the corresponding low resistance is connected between another input and grounding, a larger feedback resistor is used between negative input and output, this structure can effectively solve the matching problem of low-impedance and high-impedance CMOS. In addition, the noise voltage from VBIAS terminal can be effectively reduced by increasing the ratio of the bias resistor and the detector resistance. The whole circuit is designed two grade. The first grade is adopted bridge input structure, this structure is fit for low impedance detector. The positive amplifying method is applied in second grade . The first grade feedback resistance is designed 1M ohm, the circuit is supplied by +/-1.5V. The testing showed that the circuit can work well when it connects with low-impedance infrared photoconductive detector at the liquid nitrogen low temperature. The magnification is up to 30000 times, 3dB bandwidth is more than 4kHz, the equivalent input noise is near 1.5 micron volts. This circuit has perfectly solved the matching problem between high impedance CMOS circuit and low impedance detector.

  1. 小波滤波与QRS波检测%Wave fiitering and QRS detection.

    Institute of Scientific and Technical Information of China (English)

    杨思军; 郝继飞; 闫文杰; 丁小平

    2011-01-01

    利用双正交样条小波等效滤波器,实现了 ECG 信号的小波分解和重建.分析心电信号奇异点与其小波变换模极大值对的零交叉点的关系,提出了心电信号 QRS 波检测的算法.在检测算法中还使用了一系列策略来提高算法的抗干扰能力和 QPS检测的准确性.经 MIT/BIH 心律失常数据库验证,QRS 波的正确检测率达 99.506%.最后将该算法应用到 Windows Mobile 智能手机上的心电监护系统中,达到令人满意的效果.%ECG signal's decomposer and reconstruction have been achieved by using a biorthogonal filter bank based on quadratic spline wavelet. Analyzing the relationship between the signal singularity and the zero-crossing point of the modulus maximum pair of its wavelet trausform, QRS complexes detected arithmetic is proposed. Some strategies are applied to improve the arithmetic anti-jamming ability against noise and to increase the QRS detection veracity. The correctness of QRS complexes detection rate can be up to 99.506%,which has been validated by MIT/BIH ECG signal database. Finally,this arithmetic is applied to the ECG monitoring system based on the Windows Mobile smart phones and achieves satisfactory results.

  2. 髋关节股骨近端CT序列图像外轮廓提取研究%Extern contour extraction research for proximal femur in CT ;images of hip joint

    Institute of Scientific and Technical Information of China (English)

    罗三定; 刘倩兰; 陈远兵; 邹峥

    2014-01-01

    In order to segment the extern contours of hip joint correctly and effectively, a kind of extraction method for extern contour of proximal femur is presented based on the best segmentation curve. The proposed method can find a closed seg-mentation curve which segments target femur part against remaining femur part by the virtue of frame similarity for bottom up CT image sequences, so as to locate the position of the target femur accurately, and search for the edge point by the vir-tue of the segmentation carve. The result of the experiments show that the proposed method can extract the extern contour of proximal femur from CT images accurately with strong adaptivity and good anti-jamming.%为正确有效地分割出髋关节的外轮廓,提出了一种基于最佳分割线的股骨近端外轮廓的提取方法。该方法利用自底向上CT序列图像的帧间相似性找到一条分割目标股骨与其他骨骼的闭合分割线,从而利用该分割线来精确定位目标骨骼的位置,并搜索边缘点。实验结果表明,该方法能够准确地识别出股骨近端的外轮廓,自适应强,抗干扰性好。

  3. COMPASS/CAPS组合导航接收机设计与实现%Design and Implementation of COMPASS/CAPS-Based Integrated Navigation Receiver

    Institute of Scientific and Technical Information of China (English)

    闫舟

    2013-01-01

      As an innovative system on our own, the COMPASS navigation system and the CAPS navigation system complement each other perfectly in practical applications. The COMPASS/CAPS-based receiver is designed based on the characteristics of COMPASS and CAPS system described in the paper. The acquisition and tracking algorithm are presented and the test of the receiver is implemented. The test result shows that the COMPASS/CAPS-based receiver has higher performance and more perfect functions, in such special applications as anti-jamming, than a single COMPASS system receiver.%  COMPASS系统和CAPS系统作为我国自主研发的卫星导航系统,它们在实际使用时具有较强互补的特性。本文研究了 COMPASS 系统和 CAPS 系统的特点,利用 CAPS 系统和COMPASS系统的特性设计了COMPASS/CAPS接收机,详细给出捕获、跟踪算法设计,并对设计的接收机进行了测试。测试表明,设计的COMPASS/CAPS接收机性能良好,相对单COMPASS系统,COMPASS/CAPS接收机在抗干扰特性,特定的应用场合上的功能和性能有了较大的提高。

  4. Improvement of clustering algorithm FEC for signed networks%符号网络聚类算法FEC的改进

    Institute of Scientific and Technical Information of China (English)

    孔令旗; 杨梦龙

    2011-01-01

    The Finding and Extracting Community (FEC) algorithm has some disadvantages as the algorithm stability is not enough, and the quality of extracting community needs to be improved.To solve these problems, some improvements were made from the following aspects: Add the function of selecting target vertex before random walk; cancel the parameter of random walk steps of the original algorithm by using a method of detecting steps automatically; supplement the quality evaluation of the link between the communities on the base of the original community extraction; achieve the controllability of particle size of community by introducing the threshold parameter.The results show that the improved algorithm has some improvements at the aspects of stability, anti-jam performance and clustering analysis.%针对FEC算法存在的稳定性不够、网络簇抽取质量亟待提高等问题,从以下几个方面对原算法进行了改进:在随机游走前添加了选择目标顶点功能;采用自动步数探测法取消了原算法的随机游走步数参数;在原有的簇抽取评价条件的基础上补充了簇间连接权重评价;通过引入阈值参数实现了簇抽取粒度的可控性.测试结果表明,改进后的算法在稳定性、抗干扰性和聚类分析质量等方面比原算法都有所提高.

  5. 低冗余灰度成像技术在反舰导弹末制导中的应用%An Application of Low-redundancy Gray-scale Imaging Technology in the Terminal Guidance of Anti-ship Missile

    Institute of Scientific and Technical Information of China (English)

    李伟; 芮震峰; 孥树军

    2012-01-01

    在对反舰导弹特点和主要几种反舰导弹末制导干扰与反干扰原理进行分析的基础上,提出了基于灰度成像技术的导弹末制导控制办法。在参阅已有文献的基础上,从可行性方面进行了论证,给出了系统设计流程图,列出了相应的数据转换公式,进行了时间处理上的对比验证。这种"低冗余"的红外灰度图像作为信息源具有信息处理所需时间短、排除干扰效率高的优点,有利于提高现代反舰导弹的突防命中能力。%According to analysis the features of anti-ship missile and the contrast for several main guidance and anti-guided ways,a gray-scale imaging based terminal guidance method was put forward.With the help of extant literature achievements,the feasibility of the programe was discussed,the sysyem design flow and the corrresponding data conversion formula were showed,then,the contrast verification on the time processing was carried out.Such a so called "low-redundancy" infrared gray imaging technology witnessed an advantage of shorter information processing time and higher anti-jamming efficiency,which can serve as a reference for the overall design of the modern anti-ship missiles.

  6. Pilot-based channel estimation for adaptive OFDM communication systems of indoor visible light%基于导频的室内可见光自适应OFDM通信系统信道估计

    Institute of Scientific and Technical Information of China (English)

    黄震宇; 郭树旭; 张择书

    2014-01-01

    使用自适应OFDM技术改善可见光通信系统性能,需要以准确的信道估计为前提。研究可见光自适应OFDM通信系统的基于导频的信道估计方法,引入射频通信中常用的LMS方法,与可见光信道基于LS的估计方法进行了比较,并对其特性进行了分析,仿真实验结果表明,采用LMS估计方法在BER为10-3水平时,SNR优于LS估计方法2 dB,LMS信道估计方法信道跟踪能力较强,比LS法抗干扰。%Based on accurate channel estimation,adaptive OFDM technology can be used to improve the visible light com-munication system performance. The method of pilot-based channel estimation used in visible light adaptive OFDM communica-tion systems is researched by introducing the LMS methods which is commonly used in the RF communication. Through com-pared with the existing LS-based estimation methods,their characteristics are analyzed. The simulation results show that when BER turns to be 10-3 with LMS estimation method,the SNR can be 2dB better than LS method. So the channel tracking ability of LMS channel estimation method is stronger,and the anti-jamming capability is better than LS method.

  7. Design and Implement of System the Electromagnetic Launcher Based on DSP%基于DSP电磁轨道炮控制系统设计与实现

    Institute of Scientific and Technical Information of China (English)

    牛颖蓓

    2012-01-01

    In order to achieve autocontroL This report designs hardware and software about control system of electromagnetism rail gun with corresponding data analysis during emitting. The system adopts time sequence control mode of synchronization triggering and collects discharging current waves. Then this report analyzes the whole system performance with comparisons between electromagnetism rail guns with different lengths. The result shows that with different charging voltage the electromagnetism rail is longer and the discharging pulse is wider, the system efficiency is better. The system with DSP autocontrol has high response speed, high anti-jamming and high accuracy of test data.%在电磁轨道炮发射过程中,为了实现自动控制并结合相应数据分析电磁发射过程中各系统的运行状态和整体系统性能;从硬件和软件两个部分设计实现了电磁轨道炮控制系统,采用同步触发时序控制方式,进行放电电流波形采集;通过对比轨道炮的不同长度分析整个系统性能;实验结果表明,电磁轨道炮充电电压变化时,电磁轨道越长,放电脉宽增加,系统的整体效率得到提高;采用DSP控制系统对电磁轨道炮进行自动控制,具有反应速度快、抗干扰能力强、试验数据精度高等优点.

  8. Implementation of Particle Filter Tracking Algorithm Resisting to Laser Speckle Jamming%抗激光散斑干扰的粒子滤波跟踪算法硬件实现

    Institute of Scientific and Technical Information of China (English)

    程玉宝; 蒋斐; 倪家正

    2012-01-01

    针对传统的电视跟踪系统在激光散斑干扰下跟踪效果不佳的问题,对抗干扰性较强的粒子滤波跟踪算法进行了硬件实现并改进.首先基于“DSP+ ARM”技术架构设计了电视跟踪仿真平台;然后对裂变自举粒子滤波跟踪算法进行了研究,并结合仿真平台进行了工程化改进、优化和实现,提高了运算速度,满足了高效性和实时性的跟踪要求.实验结果表明,该仿真平台能够运行改进的裂变自举粒子滤波算法,达到实时稳定的跟踪要求,具备一定的抗激光散斑干扰的能力.%To solve the problem that the traditional TV-guided system may fail to track the object under laser speckle jamming,the particle filter tracking algorithm,which has stronger jamming resisting capability, was implemented and improved. Firstly, a TV-tracking platform was designed by "DSP + ARM" technology framework. Then,the Fission Bootstrap Particle Filtering (FBPF) was studied,improved and implemented on the platform, the operating speed was improved, which could meet the high-efficiency and real-time tracking demands. Simulation experiment result proved that the platform can implement the improved fission bootstrap particle filter algorithm, meet the real-time and stable tracking demand, and have certain anti-jamming capability.

  9. [Research on lateral shearing interferometer for field monitoring of natural gas pipeline leak].

    Science.gov (United States)

    Zhang, Xue-Feng; Gao, Yu-Bin

    2012-09-01

    Aimed at the mechanical scanning spectroscopy equipment with poor anti-interference and anti-jamming ability, which affects the accuracy of its natural gas pipeline leak detection in the wild, a new type of lateral shearing interferometer system was designed. The system uses a beam splitter to get optical path difference by a mechanical scanning part, and it cancel the introduction of external vibration interference through the linkage between the two beam splitterw. The interference intensity of interference fringes produced was calculated, and analysis of a rotating beam splitter corresponds to the angle of the optical path difference function, solving for the maximum angle of the forward rotation and reverse rotation, which is the maximum optical path range. Experiments using the gas tank deflated simulated natural gas pipeline leak process, in the interference conditions, and the test data of the type WQF530 spectrometer and the new type of lateral shearing interferometer system were comparedt. The experimental results show that the relative error of both systems is about 1% in indoor conditions without interference. However, in interference environment, the error of WQF530 type spectrometer becomes larger, more than 10%, but the error of the new type of lateral shearing interferometer system is still below 5%. The detection accuracy of the type WQF530 spectrometer decreased significantly due to the environment. Therefore, the seismic design of the system can effectively offset power deviation and half-width increases of center wavelength caused by external interference, and compared to conventional mechanical scanning interferometer devices the new system is more suitable for field detection. PMID:23240445

  10. 嵌入式技术的智能车系统设计与实现研究%Intelligent Vehicle System Based on Embedded Systems

    Institute of Scientific and Technical Information of China (English)

    任肖丽; 黄婉刁; 卢孙平; 王骥

    2014-01-01

    基于 MC9 S12 XS128的智能车,通过对道路图像进行采集和处理,再利用算法控制策略、PID控制原理和 PWM控制技术对智能车转向和速度进行控制,使小车能够自主行驶,通过使用 CodeWarrior 软件编程和 BDM调试实现小车行驶控制。本文基于 PID算法提出了改进的算法,经实物验证,所设计的智能车系统能有效循迹,保持在道路中间快速行驶,可以实现提前转弯,且系统具有较好的抗干扰能力。%The intelligent vehicle based on MC9S12XS128 collects and processes image information by the camera,and then uses algo-rithm control strategy,PID control principle and PWM control technology to control the steering and speed of intelligent vehicle,so that the car is capable of road self-identification,independent drive,and finally the car driving control using CodeWarrior software program-ming and BDM debugging.In this paper,an improved algorithm based on the PID algorithm is proposed.By physical verification,the design of the intelligent vehicle system can effectively track,keep moving fast in the middle of the road,turn in advance,and the system has better anti-jamming capability.

  11. 基于模糊控制的光伏发电系统MPPT设计%Design of MPPT in photovoltaic generation system based on fuzzy control

    Institute of Scientific and Technical Information of China (English)

    荆红莉; 赵鹏

    2016-01-01

    为了提高光伏发电的效率 ,分析了光伏发电系统最大功率点跟踪控制的原理 ,选出了实现最大功率跟踪的硬件电路.针对光伏电池输出的非线性特点 ,提出了将模糊控制应用于光伏发电的 MPPT 控制中 ,设计了模糊控制器 ,并在正常光照及光照强度变化的条件下对模糊算法控制系统和扰动观察算法控制系统进行了仿真实验 ,得出两种算法控制下系统输出的电压波形.通过对波形的对比分析 ,进一步证明了模糊 MPPT 控制系统响应快 ,抗干扰能力强 ,系统稳定性好.%In order to improve the efficiency of the photovoltaic power generation ,this paper analyzed the photovoltaic maximum power point tracking control system principle ,choosed the hardware circuit to achieve maximum power track-ing .According to the nonlinear characteristics of photovoltaic cells output ,fuzzy control is put forward to the application of photovoltaic power generation MPPT(maximum power point tracking) control ,the fuzzy controller is designed ;and under the condition of the normal illumination and the disturbance of light intensity observed output voltage waveforms of fuzzy system and P&O system by simulation experiment .Through comparison and analysis of waveforms proved that the fuzzy MPPT control system has faster response speed ,better stability and stronger anti-jamming ability .

  12. 循环流化床锅炉主蒸汽压力模型预测控制%Model predictive control based main steam pressure control system for CFB boilers

    Institute of Scientific and Technical Information of China (English)

    钱虹; 杨祖魁; 金蔚霄; 房振鲁

    2015-01-01

    Due to large time delay of the main steam pressure control system in CFB boilers,the convention-al PID and PI control methods are unable to obtain well control effect.Thus,a method based on the model predictive control (MPC)algorithm was proposed.The MPC algorithm was applied in the main steam pres-sure control regulator,and load disturbance simulation test was carried out to further verify the model pre-dictive control result.The simulation results show that,compared with the conventional PID and PI control systems,the MPC algorithm based main steam pressure control system has better stability,adaptability,ro-bustness and stronger anti-jamming performance.%由于循环流化床(CFB)锅炉主蒸汽压力控制系统的大延时性,使得常规 PID,PI 控制方法难以取得较好的调节效果。对此,提出了一种基于模型预测控制(MPC)的主蒸汽压力控制方法,将该算法运用于主蒸汽压力控制系统,并对系统进行负荷扰动仿真试验,以验证控制效果。结果表明,基于 MPC 的主蒸汽压力控制系统稳定性、适应性、鲁棒性和抗干扰能力均优于常规 PID,PI 控制。

  13. Research on the FFT Fast Acquisition Method to Suppress Repeater Spoofing Interferences%抗转发干扰FFT快速捕获方法研究

    Institute of Scientific and Technical Information of China (English)

    龚文飞; 孙昕

    2011-01-01

    The problem of suppressing the repeater spoofing interferences effectively has become a must for the design of military anti-jamming satellite navigation receivers. By analyzing the code phase characteristic of satellite signals and repeater spoofing interferences, this research proposes a method of FFT fast acquisition of long code based on delay-waiting strategy. The method distinguishes satellite signals from repeater spoofing interferences according to the code phase information of the correlation peak whose amplitude is above the threshold. Thus the acquisition performance in the scene of repeater spoofing interferences can meet the demand without degradation in normal conditions. The theory analysis and simulation results validate the effectiveness of proposed method.%为了解决有效抑制转发式干扰问题,根据转发干扰信号的码相位滞后于卫星导航信号的特点,结合快速傅里叶变换(FFT)快速捕获的二维搜索策略,提出基于延迟-等待捕获策略的抗转发干扰FFT快速捕获方法.该方法根据过门限峰值的码相位信息来区分判别卫星导航信号和转发干扰信号,在不影响接收机在无转发干扰正常工作的条件下,保证了接收机在转发干扰下的捕获性能.理论分析和仿真实验验证了该方法的有效性.

  14. Research on intelligent algorithms DC brushless speed control system cutting machine%应用于裁断机中无刷直流电机调速系统的智能算法研究

    Institute of Scientific and Technical Information of China (English)

    王法龙; 郑明辉

    2015-01-01

    针对常规PI在无刷电机调速中控制精度低及动态性能差,无法满足裁断机对动力辊电机速度控制要求,本文提出了一种自适应模糊PI控制方法。该方法应用于无刷直流电机双闭环控制的速度外环控制,提高了无刷直流电机的控制精度和动态响应性能。通过Matlab进行仿真,仿真结果表明,采用自适应模糊PI控制相对常规PI控制,无刷直流电机的调速系统具有很好的动态和静态性能,快速响应,超调量小,抗干扰能力强,鲁棒性好。%In the conventional PI control of brushless motor speed low precision and dynamic performance is poor, unable to meet the power roller cutting machine for motor speed control requirements, we propose an adaptive fuzzy PI control method. The method is applied to double-loop control of brushless DC motor speed outer control, improved control accuracy and dynamic response performance brushless DC motor. Through Matlab simulation results show that the adaptive fuzzy PI speed control system to control relative to conventional PI control, brushless DC motor has a good dynamic and static performance, fast response, small overshoot, and strong anti-jamming capability, robustness.

  15. The design of an ultra-wideband miniaturized GPR antenna%一种超宽带小型化探地雷达天线的设计

    Institute of Scientific and Technical Information of China (English)

    彭宇; 王蕾; 郭福强; 胡通海

    2014-01-01

    通过对蝶形偶极子天线复合加载的方式形成一种小型化的探地雷达天线,多种加载方式的引入不但使天线具有宽频带的性能,而且设计的天线尺寸与理论计算尺寸相比也大大减小。在天线后方引入背腔设计,增加了天线的方向性和抗干扰能力。所设计的天线具有1.5~4 GHz的频带宽度,且天线的方向性良好。设计的天线已成功应用于LTD探地雷达2.2 GHz天线系统和3 GHz的液态危险品检测天线系统中。%A kind of miniaturized GPR antenna was designed through complex loading to the bow-tie dipole. The introduction of multi-ple loading methods not only makes the antenna acquire the performance of broadband but also greatly decreases the size of antenna compared with the theoretical calculation size. By introducing back cavity behind the antenna, the directivity and anti-jamming capabili-ty of the antenna are enhanced. The designed antenna possesses a 1.5 GHz~4 GHz frequency band width and a good direction. The de-signed antenna is successfully applied to the antenna system of 2.2 GHz LTD series of GPR. This designed antenna can be also used in the dangerous liquid goods inspection system of 3 GHz LTD series of GPR.

  16. Experimental study of the thermal characteristic of submarine wake in the temperature stratified flow%温度梯度环境中潜艇尾流热特征的试验研究

    Institute of Scientific and Technical Information of China (English)

    张修峰; 杨立; 吴猛猛; 杜永成

    2011-01-01

    改进了用于实验室热尾流测量的温度测量系统,提高了系统的集成度和抗干扰能力.在水槽中实验研究了螺旋桨推进潜艇模型在有、无温度分层流体中尾流的热特征,得到两种条件下尾流的温度分布和信号衰减规律,分析了两种尾流信号的形成机理及其影响因素,表明在温度分层环境中"冷尾流"信号对探测和识别水下航行的潜艇更为有利,所得结果可为红外反潜和潜艇红外隐身提供更加切合实际的理论支撑.%In order to advance the integration level and the anti-jamming capability of the system, this paper improves the temperature measure system which is used in measuring thermal wakes in the laboratory. The thermal characteristic of thermal wake of the submarine model driven by screw propeller was studied in the flow with or without thermal stratification in the water tank, and temperature distribution of the wake and the signal decay laws were obtained under the two conditions. The formation mechanisms and main effect factors of the wake signals were analyzed, and it shows that “the cold wake” signal is more beneficial of detecting and distinguishing underwater submarine. The results obtained can provide much more practicable theoretical support for the development of technology in infrared detection of submarine and its infrared stealth.

  17. Design of Power Conditioning System in Superconducting Magnetic Energy System Based on Voltage Source Converter%基于VSC的超导储能装置中功率调节系统的设计

    Institute of Scientific and Technical Information of China (English)

    张金良; 周博曦; 卞秋野

    2013-01-01

      针对超导储能装置中基于电压源型变流器的功率调节系统,给出了基于电压源型变流器(VSC)和斩波器(Chopper)的超导储能(SMES)装置功率调节系统(PCS)的主电路拓扑结构和使用占空比表达的PCS低频数学模型,提出了使用非线性变换实现状态方程线性化的方法,通过状态方程的线性化实现有功功率、无功功率及直流侧电压解耦控制的系统设计。Matlab/Simulink环境下系统仿真结果表明,设计的PCS系统控制器对阶跃和正弦波功率指令具有很强的跟踪能力,且直流侧电压有很强的抗干扰能力。%Aiming at the power conditioning system (PCS) in the superconducting magnetic energy system (SMES) based on volt-age source converter (VSC), this paper gave the main circuit structure of PCS in the SMES based on the VSC and Chopper, as well as the low-frequency mathematical model of PCS which is expressed in the functions of duty ratio. The non-linear transformation was used to linearize state equations to realize the decoupled control between active power, reactive power and DC voltage. The simulated results in Simulink of Matlab showed that the designed PCS has perfect performance in tracing power orders in the form of step and sine waves with strong anti-jamming ability for voltage at DC side.

  18. 基于89C51智能交通灯系统的设计与仿真%Design and Simulation of an Intelligent Traffic Light System Based on 89C51

    Institute of Scientific and Technical Information of China (English)

    莫小琴; 李钟慎

    2013-01-01

    基于AT89C51单片机为核心控制器,采用ISD2560作为语音录放模块,以及MAX692“看门狗”模块提高抗干扰能力,设计十字路口的交通灯智能化控制系统。实现正常时段交通信号灯的轮换,车辆闯红灯实时监控报警、紧急通行控制、语音录放、数码管倒计时等功能。利用Proteus和Keil软件对系统进行了仿真,结果表明对实现交通的快捷以及缓解交通压力具有较强的可靠性。%The paper introduces an intelligent control system of crossroads based on AT89C51 microcontroller as the core control device, using ISD2560 as voice recording module and MAX692“watchdog”module to improve the anti-jamming capability. The system completes the normal rotation of trafifc lights, real-time monitoring and alarming of vehicles running red lights, emergency trafifc control, voice recording and digital tube countdown function. Proteus and Keil software simulation results show that the designed system has strong reliability on the shortcut trafifc and ease trafifc pressure.

  19. A shutter pulse generator for high speed camera%一种用于高速摄影仪的快门脉冲发生器

    Institute of Scientific and Technical Information of China (English)

    刘春平; 李爽; 李景镇

    2013-01-01

    A shutter pulse generator was designed, which is based on the metal oxide semiconductor field effect transistor (MOSFET). By using the N-channel level shifter for driving switch groups, which consist of Series MOSFETs and controlled by programmable logic device FPGA (field programmable gate array), a high-voltage pulse is achieved with high-speed front edge and back edge, after processing by pulse forming circuit. Experimental results showed that with a load of 1. 1 μF the amplitude of pulse is 800 V and the width of pulse is 81 jxs, both its front edge and back edge lasted less than 1 (μs. The system is anti-jamming and reliable.%设计基于绝缘栅型场效应管(metal-oxide-semiconductor field-effect transistor,MOSFET)的快门脉冲发生器,将MOSFET串联作为开关组,采用电平移位法对其进行驱动,由可编辑逻辑器件FPGA控制延时触发,经过脉冲形成电路分别得到高压脉冲的快前沿与快后沿.结果表明,在1.1 μF的负载下,可获得幅值为800 V、前后沿均小于1μs、脉宽为81μs的高压快脉冲,该系统抗干扰能力强,可靠性好.

  20. 基于噪声卷积的灵巧噪声伪码调相引信干扰%Smart noise j amming based on noise convolution modulation countering pseudo-random code phase modulation fuze

    Institute of Scientific and Technical Information of China (English)

    隋鉴; 李国林; 王凌

    2014-01-01

    Pseudo-random code phase modulation fuze has become the key point of fuze countermeasure study,because of its strong anti-jamming ability.Smart noise jamming based on noise convolution modulation is proposed to counter this fuze.The mechanism of generating smart noise based on convolution modulation is stat-ed,and the output signals of the pseudo-random code phase modulation fuze is analyzed under the smart noise jamming.It is proved theoretically that the smart noise jamming could form deceptive jamming and blanket jam-ming effect on the pseudo-random code phase modulation fuze.Simulations demonstrate that the theoretical analysis is valid and the smart noise jamming is more efficient than the traditional jamming methods.%伪码调相引信的良好抗干扰能力,使其成为引信对抗研究的重点。提出了基于噪声卷积的灵巧噪声对伪码调相引信进行干扰。阐述了灵巧噪声的产生机理,推导了灵巧噪声作用于伪码调相引信时,引信输出信号的形式,理论分析证明了灵巧噪声可以对伪码调相引信形成欺骗干扰和压制干扰效果。仿真验证了理论分析的正确性,与传统干扰相比,灵巧噪声干扰的干扰效率更高。

  1. Multi-Channel Two-Photon Coding Design of Network Transmission Key Distribution Scheme%多信道双光子编码网络传输密钥分配方案设计

    Institute of Scientific and Technical Information of China (English)

    王亚子

    2014-01-01

    Noise impact, improved quantum communication to improve the anti-jamming capability and safety, to avoid the random changes in the polarization state of the photon optical birefringence effect caused a new type of quantum key distribution scheme, the program generates two-photon entangled statekey, can be a probability test control information transmission, and able to resist the the collective polarization rotation in optical fiber transmission noise and dependent polarization loss, has obvious advantages in the communication efficiency under the same anti-noise characteristics. Concludes with a discussion of this program channel, the decoder implementation problems described improved program in the prior art under the conditions of the feasibility.%为提高量子网络通信的抗干扰能力和安全性,避免光纤双折射效应引起的光子偏振态的随机改变而产生的噪声影响,改进了量子密钥分配方案,新的方案可生成双光子纠缠态密钥,并可在验证过程中进行概率检验,从而控制信息传输,新方案可抵抗光纤传输中集体偏振噪声和偏振损失的影响,在同样抗噪特性下通信效率得到很大的提升。最后分析了新方案的信道、解码器的实现方法,说明了改进后方案于现有技术条件下具有可行性。

  2. 涡旋电磁波在军事无线通信中的应用%Application of Vortex Electromagnetic Wave in Military Wireless Communication

    Institute of Scientific and Technical Information of China (English)

    晋军; 邵尉; 孟凡秋

    2014-01-01

    涡旋电磁波的OAM复用是一种把量子力学中的轨道角动量理论应用到无线通信领域的新型技术,拥有高效频谱利用和抗干扰两项引人注目的特性。介绍了国内外研究现状,对涡旋电磁波的产生与接收、OAM复用对通信容量的影响、OAM模式的复用和解复用、大气的非均匀性和电离层对涡旋电磁波的影响、涡旋电磁波抗干扰能力等研究热点进行了概括。指出了研究、分析OAM复用和抗干扰性能以及探索有效的OAM通信方法的重要意义。%Vortex electromagnetic wave OAM multiplexing is a kind of the application of the theory of quan-tum mechanics to the new technology of the wireless communication field. It has two attractive properties of high spectrum utilization and anti-interference. The present development situation both at home and abroad is introduced. The vortex electromagnetic wave's generating and receiving, OAM multiplexing of the com-munication capacity of OAM mode, the multiplexing and demultiplexing, atmospheric inhomogeneity and i-onosphere to scroll the effects of electromagnetic waves, electromagnetic vortex wave anti-interference abili-ty, etc. , are summarized. Finally,the research and analysis of the OAM multiplexing and anti-jamming per-formance,and the significance in exploring effective methods of OAM communication,are also pointed out.

  3. 一种与整车联动的残疾人踏板设计与研究%A linkage of disabled people and vehicle pedal design and research

    Institute of Scientific and Technical Information of China (English)

    赵理想

    2014-01-01

    to provide a linkage of disabled people and vehicle pedal, reliable work, the pedal is not affected by the external factors driving, can be a very good and linkage of the vehicle. Perception of persons with disabilities by electromagnetic switch pedal opening, and the signal transmitted to the vehicle controller, so as to judge whether the vehicle can be started, because the electromagnetic switch can not inlfuenced by following the closure of the pedal clearance, also not affected by the vibration of vehicle, real-time and accurate will can accurate sent to the vehicle control unit, has the characteristics of high reliability, strong anti-jamming capability, improve the performance of the vehicle safety and reliability.%提供一种与整车联动的残疾人踏板,该踏板工作可靠,不受行驶中的外界因素影响,能很好的与整车联动。通过电磁式开关来感知残疾人踏板的开度,并将信号传递给整车控制器,从而判断整车是否可以启动行驶,由于电磁式开关可以不受踏板关闭后的间隙影响,也不受车辆行驶中的震动影响,可以实时将准确的信号发送给整车控制单元,具有可靠性高、抗干扰能力强的特点,提高整车安全性和可靠性。

  4. 磁悬浮开关磁阻球体电机的数学模型及其仿真%Spherical switched reluctance motor with magnetic levitation

    Institute of Scientific and Technical Information of China (English)

    戴敏; 曾励

    2011-01-01

    针对双绕组无轴承开关磁阻电机的绕组结构复杂、绝缘程度要求高及加工成本高的缺陷,结合悬浮原理和磁阻最小原理,提出一种磁悬浮开关磁阻球体电机.分析了磁悬浮开关磁阻球体电机的基本组成和运行机理,采用磁路分割法对各部分磁路进行推导与计算,建立了球体电机的数学模型.利用Matalab/simunik软件进行仿真,结果表明电机能够实现动子快速稳定悬浮和旋转,并且具有良好的抗干扰性能.%In view of the bearingless switched reluctance motor with double windings, which has a complicated structure, an absolute insulation, and expensive manufacture cost, the paper presents a spherical switched reluctance motor with magnetic levitation on the basis of suspension theory and minimum reluctance principle. It analyses elements and machanism of the spherical switched reluctance motor with magnetic levitation, deduces and calculates the magnetic conduction of the gap by means of the magnetic segmentation. It obtaines a model building of spherical electric machines.With the Matalab/simunik model, simulation results show that the rotor realizes quick stable suspension and rotation, it has excellent anti-jamming performance as well.

  5. Magneto-resistive Proximity Switch for Gear Rotate-speed Measuring%一种可用于齿轮转速测量的磁阻式接近开关

    Institute of Scientific and Technical Information of China (English)

    秦玉伟

    2011-01-01

    介绍了一种基于磁敏电阻元件的磁阻式接近开关,设计了其信号处理电路,并将其应用于铁磁性齿轮的转速浏量.该接近开关利用磁阻效应原理制成,具有结构简单,成本低廉,灵敏度高的优点.对不同径向间距下接近开关的差程值进行测量,由实验结果可知,在3~7 mm的检测距离内,该磁阻式接近开关工作性能稳定,动态特性良好,抗干扰能力强,且工作频率范围较宽,能适应高速和低速的齿轮转速变化,可替代传统的磁电式和霍尔式转速传感器,用于铁磁性齿轮的转速测量.%A magneto-resistive proximity switch based on magnetic resistor which is used for ferromagnetic gear speed measurement is introduced, and its signal processing circuit is designed. The proximity switch with the principle of magnetoresistive effect has advantages of simple construction. low cost and high sensitivity. The path-differences with different radialdistances are measured. The experiment shows that the proximity switch has reliable performance, favorable dynamic characteristics, and good anti-jamming capability when the detection distance between 3mm and 7mm. It has wide range working frequency, is suitable for the high and low gear speed , and can replace the traditional magneto-electric and Hall speed sensors for ferromagnetic gear speed measurement.

  6. 基于自抗扰控制器的重力稳定平台控制系统研究%Gravity Stabilized Platform Control System Based on Active Disturbance Rejection Controller

    Institute of Scientific and Technical Information of China (English)

    郭斌; 许江宁; 何泓洋; 郭士荦

    2016-01-01

    Gravity stabilized platform is a kind of complex uncertain movement system which is difficult to get accurate models .It can be affected by mechanical resonance ,torque coupling ,load change and electrical parameters fluctuations ,and requires quick response speed ,strong anti-jamming capability ,and high steady state accuracy .However ,the influences and requirements are contradictory .Therefore ,an active disturbance rejection controller based on gravity stabilized platform is designed .The Simulink simulation results show that the controller possesses good response speed ,adaptivity ,fast speed , high steady accuracy ,strong robustness and anti-interference capability and isn't sensitive to the parameter change .%重力稳定平台系统是一类难以获得精确模型的复杂非线性不确定的运动系统,由于存在机械谐振、力矩耦合负载变化及电气参数波动等因素的影响,并且稳定平台系统要求具有响应速度快,抗干扰能力强,稳态精度高等优良特性。但这些性能指标之间是有矛盾的。针对这一问题,设计了基于重力稳定平台控制系统的自抗扰控制器,并进行了 Simulink仿真。仿真结果表明,该系统具有很好的响应特性、自适应性和速度快,具有很高的稳态精度,而且系统对参数变化不敏感,鲁棒性和抗干扰性都很强。

  7. Study on the determination of molybdate content in industrial circulating cooling water%工业循环冷却水中钼酸盐含量测定研究

    Institute of Scientific and Technical Information of China (English)

    白莹; 邵宏谦; 杨裴; 李琳

    2012-01-01

    A method for determinating the molybdate content in industrial circulating cooling water,i.e. thiocyanate spectrometry,is introduced. The molybdate is reduced to Mo5+ by adding 6.0 mL of sulfuric acid solution, 1.0 mL of ferrous ammonium sulphate solution, 10.0 mL of ammonium thiocyanate solution and 1.0 mL ascorbic acid solution, and forms orange complex with thiocyanate. The absorbency of the complex is determined at 460 run and the molybdate content is figured out by the calibration curve. This method is scientific and stable,and having strong capacity of anti-jamming. Its determination range is suitable for circulating cooling water.%介绍了一种测定工业循环冷却水中钼酸盐含量的方法——硫氰酸盐分光光度法.在待测水样中加入6.0 mL硫酸溶液,1.0 mL硫酸亚铁铵溶液,10.0 mL硫氰酸铵溶液以及1.0 mL抗坏血酸溶液,此时钼酸盐被还原成Mo5+,并与硫氰酸盐形成橙色络合物,在460m波长处测定该络合物的吸光度并通过标准曲线计算出钼酸盐含量.该方法科学、稳定,抗干扰能力强,测定范围适用于循环冷却水中钼酸盐含量的测定.

  8. Study on Control Strategy of 5 DOF Hybrid Robot%新型雕刻机器人控制策略的研究

    Institute of Scientific and Technical Information of China (English)

    罗继曼; 张明山; 安玉振; 孙晓伟

    2014-01-01

    Firstly ,kinematics model of the new hybrid engraving robot is created and the positive and inverse kinematics solution are calculated ;sec-ondly ,control strategy of the new hybrid engraving robot is studied and three kinds of control strate-gies ,w hich are PD algorithm ,PD gravity compen-sation algorithm and computed torque algorithm , are established ;in the end ,mathematical model of the three algorithms is simulated by Matlab/Simu-link software and compares the pros and cons of different control algorithms .It turned out that in three kinds of control strategies ,position control effect of computed torque algorithm is the best and it can ensure that the system has strong anti jam-ming .So computed torque algorithm is adopted as control strategy of the engraving parallel head .%建立了新型雕刻机器人的雕刻并联头的运动学模型,计算出了运动学的正解和反解;研究了新型雕刻并联工作头的控制策略,建立了PD算法、PD加重力补偿算法和计算力矩法3种控制策略的模型;采用Matlab/Simulink软件,仿真了3种算法搭建的数学模型,比较得出了不同控制算法的优劣。结果表明,在3种控制策略中,计算力矩法的位置控制效果最好,能够保证系统有较强的抗干扰性。所以,新型雕刻机器人选用计算力矩法作为自身的控制策略。

  9. Communication and Simulation for Unmanned Underwater Vehicle Based on CAN%基于 CAN 总线的 UUV 通信系统与仿真

    Institute of Scientific and Technical Information of China (English)

    杨培培; 赵诗雅; 刘瑞勇; 付登昊; 李闯

    2015-01-01

    针对传统采用 RS232/RS422通信的集中式控制可靠性低、抗干扰能力差、任务过多过重,部件的兼容性和系统的扩展性差等缺点,论述了基于 CAN(Controller Area Network)总线及 RS232/RS422通信协议的无人水下航行器 UUV分布式控制系统,增强了 UUV 控制系统的可靠性和容错性,介绍了对 UUV 航向和深度进行控制的半实物仿真系统,最后给出了 UUV 航向和深度控制半实物仿真的结果。%To overcome the shortcomings existing in the traditional centralized navigation and control system (which a-dopted RS232/RS422 for communication),such as the poor reliability,low anti-jamming capability,over-burden for task, and poor expansion of electronic components and systems compatibility,this paper discusses the unmanned underwater ve-hicle based on distributed control system CAN (Controller Area Network)and RS232/RS422 communication protocol to enhance the reliability and fault tolerance of UUV control system,then introduces the hardware-in-the-loop simulation sys-tem of UUV course and depth controlling.Finally,gives the simulation results.

  10. Unmanned Underwater Vehicle Depth ADRC Based on Genetic Algorithm Near Surface%基于遗传算法的无人水下航行器深度自抗扰控制

    Institute of Scientific and Technical Information of China (English)

    胡坤; 张孝芳; 刘常波

    2013-01-01

    A kind of auto disturbance rejection controller(ADRC) based on genetic algorithm for keeping UUV depth was designed according to the characteristics of UUV maneuvering. Because of more parameters of ADRC, its parameter design was transformed to parameter optimization. The controller parameter of ADRC in a UUV depth control system was optimized by using the genetic algorithm. The depth control of UUV was simulated without disturbing and near the surface. The simulation results show that the ADRC controller has better depth keeping and anti-jamming performances. Compared with the conventional PID controller, the amplitude and the frequency of steering controlled by ADRC controller are reduced much more obviously. The control quality of ADRC is significantly improved.%根据无人水下航行器(UUV)操纵控制过程的特点,设计了一种基于遗传算法的UUV深度自抗扰控制器(ADRC).针对ADRC控制器控制参数较多的问题,将其参数设计转化为一种辨识问题.借助遗传算法,对UUV深度控制系统中的ADRC控制参数进行了辨识,并对其在无外界干扰和近水面航行受波浪力干扰两种情况下的深度控制进行了仿真.数值仿真结果表明,ADRC控制可以获得较好的深度保持性能,并且具有较强的抗干扰能力.与PID控制相比,ADRC控制的操舵幅度和操舵频率有了明显降低,其控制品质有了明显提高.

  11. Measurement and Control System for Ratory Balance Equipment in Wind Tunnel Test%风洞旋转天平试验装置测控系统

    Institute of Scientific and Technical Information of China (English)

    宋晋; 孙棣华; 赵敏; 刘赟; 马军

    2016-01-01

    The rotary balance is used for simulating spin state in wind tunnel, and getting aerodynamic force data at the same time. In order to make the measurement and control system have the characteristics of high automation, high precision and strong anti-jamming ability, the paper designs and realizes the system for wind tunnel. It includes 3 subsystems, which are the test management, the data acquisition and the motion control. The test result shows, the system can run automatically under the control of test management subsystem, achieve kinds of motion control and get data in complex electromagnetic environment. The system is simple, stable and reliable. The design idea and the techniques have a certain reference value.%旋转天平是一种用来模拟飞机尾旋并获取气动力的试验装置,为使该装置的测控系统具有自动化程度高、测试精度高和抗干扰能力强的特点,设计并实现了一套应用于风洞旋转天平的测控系统。该系统包括了试验管理、天平数据采集和旋转运动控制3个子系统。测试结果表明:该系统可在试验管理子系统的调度下自动化运行,能够实现试验所需的多种运动控制,并能在复杂电磁环境下完成数据采集。该系统操作简单、稳定可靠,设计思路及所采用的技术具有一定的参考意义。

  12. Performance Analysis and Simulation of M-ary Direct Sequence Spread Spectrum System%多进制直接序列扩频系统性能分析及仿真

    Institute of Scientific and Technical Information of China (English)

    夏高峰; 罗宇; 金哲仕

    2015-01-01

    Spread spectrum system can effectively improve the anti-jamming capability of communication systems;and it has been widely applied in military communication systems as well as in civilian communication systems. M-ary direct sequence spread spectrum system has its unique advantages and is proven widely applicable. This paper studies on M-ary Direct Sequence Spread Spectrum System, and introduces the theory, the performance and channel coding. Results of performance analysis and simulation indicate that the M-ary direct sequence spread spectrum system has good performance and can be applied to bandwidth constrained systems.%扩频技术能有效提高通信系统抗干扰能力,因此在军事通信及民用通信领域得到了广泛应用。多进制直接序列扩频相对于直接序列扩频具有其特有的优势和较强的实际应用背景。本文对多进制正交扩频系统进行研究,介绍了多进制直接序列扩频的原理、分析了多进制直接扩频系统的误码性能,并研究了适合多进制直接扩频系统的信道编解码。仿真结果表明,多进制扩频具有良好的性能,适合带宽受限系统。

  13. Spread spectrum communication based on hardware encryption%硬件加密的扩频通信方案

    Institute of Scientific and Technical Information of China (English)

    萧宝瑾; 仝海丽; 张建忠; 张朝霞; 王云才

    2011-01-01

    提出了一个利用混沌激光源产生1Gbit/s的随机序列作为扩频码的方案.理论分析表明,该随机序列克服了伪随机序列的周期性,在扩大扩频码容量的同时实现了扩频码可变,提高了通信安全性.利用Simulink软件对该扩频系统进行仿真.结果表明,当信息速率一定时,扩频增益越大,误码率越低,与理论结果相符.与传统的扩频系统相比,该方案在提高系统抗干扰能力的同时也增强了保密性.%The scheme of 1 Gbit/s random sequence generated by chaotic laser as spreading code is proposed.Theoretical analysis indicates that the pseudo random sequence exhibited periodic behavior is eliminated by the random sequence and the capability of spreading code is enlarged.Meanwhile,the communication security can be improved by variable spreading code.The corresponding spread spectrum system is numerically simulated by Simulink software and the results demonstrate that the greater the used spreading gain,the lower the obtained error rate will be when the information speed is constant,which is consistent with the theoretical results.The anti-jamming ability of the spread spectrum system is strengthened and the security is enhanced compared with those of the traditional spreading system.

  14. Cycle Shift Spread Spectrum Technology in Underwater Acoustic Communication%循环移位扩频水声通信技术研究磁

    Institute of Scientific and Technical Information of China (English)

    王喜龙; 张琳琳; 郭小宇

    2014-01-01

    Direct sequence spread spectrum communication system can work reliably in low SNR conditions ,and has great ability of anti multipath and anti -jamming because of its excellent related performance .This is extremely valuable for information transmission without error in underwater acoustic communication .However ,the communication rate of routine direct sequence spread spectrum underwater acoustic communication system is very low ,according to this characteristic ,this article studies the mode of cycle shift spread spectrum underwater acoustic communication ,and it increases communication rate of direct sequence spread spectrum communication system in the proposition of to promise a certain anti-interference abil-ity .%直接序列扩频通信系统因为其优良的相关性能,能够在较低的信噪比条件下进行可靠地工作,而拥有良好的抗多径和抗干扰的能力。这对于水声通信信息的无误码传输都是极为可贵的。可是,常规的直接序列扩频水声通信系统的通信速率很低,针对这一特点,论文研究了循环移位扩频水声通信方式,它在保证一定抗干扰能力的前提下成倍数提高直接序列扩频通信系统的通信速率。

  15. Technology Status and Developing Trends of Satellite Phased Array%星载相控阵天线的技术现状及发展趋势

    Institute of Scientific and Technical Information of China (English)

    阎鲁滨

    2012-01-01

    星载相控阵天线采用现代微波集成技术,在有限的卫星平台空间条件下,实现独立控制的多个点波束,满足未来通信的需求。相控阵天线可以实现波束间通信容量的调整,还可以根据需要改变波束形状,使用自适应调零的抗干扰技术,这些技术已在国外星上设备中广泛采用,具有广阔的发展前景。文章介绍了星载相控阵天线的研究现状、关键技术,以及发展趋势,并对我国星载相控阵天线技术的发展提出了建议。%Satellite phased array with modern microwave integrated circuit technology takes limit space on satellite and is able to independently control many beams to satisfy the demands ofmod- ern communication. The power ration between beams of phased array is adjustble. The radiation beam shape is variable and adaptive anti-jamming technology is easy to apply. Satellite phased ar- ray has been applied in wide domain and has increasing developing future. This paper gives the research status of satellite phased array, the key technologies and prospects the developing trends of satellite phased array.

  16. 基于压缩感知的短波多天线分集合并接收方法%Diversity Combination Receiving Method based on short wave antenna of Compression Perception

    Institute of Scientific and Technical Information of China (English)

    徐婷; 彭亚红; 罗建宝; 刘俞伯

    2012-01-01

    In the shortwave communication,in order to overcome the influence of receipt signal such as the multipath interference,decline and doppler frequency shift and so on in the channel,and realize high signal speed transmission under low SNR,diversity combination receiving system design method based on short wave antenna of compression perception was presented this paper.The system had some features such as high frequency spectrum efficiency,strong anti-jamming abilityand high precision with a low sampling rate by combining OFDM modulation mode with compression perception.The experimental results showed that the existing shortwave communication system has an optimal reconstruction performance in noise jamming and high-speed transmission.%在短波通信中,为了克服信道中的多径干扰、衰落和多普勒频移等对接收信号的影响,实现低信噪比下,信号高速传输,文章提出了一种基于压缩感知的短波多天线分集合并接收系统设计方法。该系统有效地将OFDM调制方式和压缩感知相结合,充分利用了OFDM调制方式频谱效率高、抗多径衰落能力强等优势以及压缩感知抗干扰能力强、能以低采样率高精度重建待测信号的特性。实验结果表明:与现有的短波通信系统相比,在信号受强噪声干扰且高速传输的情况下,重建性能最优。

  17. A Novel Approach to Beam Steering Using Arrays Composed of Multiple Unique Radiating Modes

    Science.gov (United States)

    Labadie, Nathan Richard

    Phased array antennas have found wide application in both radar and wireless communications systems particularly as implementation costs continue to decrease. The primary advantages of electronically scanned arrays are speed of beam scan and versatility of beamforming compared to mechanically scanned fixed beam antennas. These benefits come at the cost of a few well known design issues including element pattern rolloff and mutual coupling between elements. Our primary contribution to the field of research is the demonstration of significant improvement in phased array scan performance using multiple unique radiating modes. In short, orthogonal radiating modes have minimal coupling by definition and can also be generated with reduced rolloff at wide scan angles. In this dissertation, we present a combination of analysis, full-wave electromagnetic simulation and measured data to support our claims. The novel folded ring resonator (FRR) antenna is introduced as a wideband and multi-band element embedded in a grounded dielectric substrate. Multiple radiating modes of a small ground plane excited by a four element FRR array were also investigated. A novel hemispherical null steering antenna composed of two collocated radiating elements, each supporting a unique radiating mode, is presented in the context of an anti-jam GPS receiver application. Both the antenna aperture and active feed network were fabricated and measured showing excellent agreement with analytical and simulated data. The concept of using an antenna supporting multiple radiating modes for beam steering is also explored. A 16 element hybrid linear phased array was fabricated and measured demonstrating significantly improved scan range and scanned gain compared to a conventional phased array. This idea is expanded to 2 dimensional scanning arrays by analysis and simulation of a hybrid phased array composed of novel multiple mode monopole on patch antenna sub-arrays. Finally, we fabricated and

  18. On the Control Scheme of Each Digital and Analog Quantity of the Reactor%反应器各数字量与模拟量的控制方案研究

    Institute of Scientific and Technical Information of China (English)

    唐令怡

    2015-01-01

    With the continuous development of science and technology, the demands of industrial production process for automation are higher and higher. In order to achieve the optimal control effect and control accuracy, this paper uses Siemens PCS7, WinCC software and PLC400 controller to design the control scheme of the reactor. Through analyzing the different control requirements and characteristics of the different control variables, the most suitable control scheme is gotten. Then, the proportional control, cascade control, PID control and fuzzy PID control are adopted to realize the effective control of the temperature, liquid level, reactant concentration, pressure and product concentration for the reactor. At the same time, the good anti-jamming ability of the system is ensured. Finally, the configuration of communications, hardware and monitoring picture is implemented by Siemens PCS7 and WinCC software, and a set of complete, available plan of control system is accomplished.%随科技的不断发展,工业生产过程对自动化的需求越来越高。为了达到最优的控制效果与控制精度,本文采用基于西门子PCS7、WinCC软件和PLC400控制器的对反应器的控制方案设计。控制方案的确定是通过对不同控制变量不同的控制需求和控制特点的分析,得到最适合的控制方案。最终采用了比例控制、串级控制、PID控制和模糊PID控制,实现了对反应器的温度、液面、反应物浓度、压力以及产物浓度的有效控制。同时,也保证了系统具有良好的抗干扰能力。最后,利用西门子PCS7和WinCC软件,实现了通讯、硬件和监控画面的组态,最终成为一套完整、可用的控制系统方案。

  19. Technology of high density resistivity method for bedrock investigation%高密度电阻率法在基岩勘察中的应用

    Institute of Scientific and Technical Information of China (English)

    邓帅奇; 岳建华; 刘志新; 于业斌

    2012-01-01

    Based on the fundamental theory of tripotential sonde, the paper explained the principle, working method, the process of data processing of high density measurement method of electrical resistivity, and applied it to actual engineering. Through examples of analysis, Wenner array has obvious effect for detecting the up and down situation of bedrock surface due to its high vertical resolution. In addition, Wenner array has advantage of strong signal acquisition and high signal-to-noise ratio. Instead, dipole array has high sensitivity for detecting the internal structure of the bedrock due to its high transverse resolution. While dipole devise also has weak capability on signal acquisition and low ability of anti-jamming. To sum up, the paper concluded that it should get an ideal detecting results by combination. The actual application indicated that this method can get good result of detecting bedrock. It is proved by practice that the application of high density resistivity method in bedrock investigation can get great result. Furthermore: it would do great help to improve the exploration results and accuracy by combining different arrays for comprehensive measurement.%从三电位电极系基本理论出发,对高密度电阻率法常用温纳、偶极及微分装置的分辨率、信号强度等进行了比较研究.实例分析表明,温纳装置测量获得的数据纵向分辨率较高,采集信号的强度大,信噪比高,采用该装置探测基岩面的起伏状况效果明显;偶极装置采集的数据横向分辨率较高,在探测基岩内部构造方面有较好的灵敏度,但该装置采集的信号强度小,抗干扰能力差.在实际应用时,建议运用多种装置形式进行综合测量和对比解释,以进一步提高勘探效果和精度.

  20. 深基坑工程钢支撑轴力实测分析与预测%Analysis and Prediction to Steel Support Axial Force in Deep Excavation

    Institute of Scientific and Technical Information of China (English)

    刘斌

    2013-01-01

      随着地下空间的开发利用,各种深基坑工程不断涌现,钢支撑技术因施工方便在深基坑设计中广泛应用。目前,对钢支撑系统的研究多采用传统理论和数值模拟技术,这些方法对模型的基本参数有严格要求,通常情况下很难取得。人工神经网络具有很强的学习、联想和抗干扰能力,在预测分析等方面表现出极大的优势。本文以青岛地铁火车北站深基坑工程为背景,通过钢支撑轴力现场监测得到轴力变化规律。研究深基坑支撑轴力变化影响因素,将各因素根据一定规律进行划分,建立了钢支撑轴力影响因素的评价指标体系。并基于人工神经网络对钢支撑轴力进行预测,预测数据和实测数据吻合较好。%  With the development and utilization of underground space, a variety of deep foundation pits are constantly emerging. The steel support technology is widely used in deep foundation design because of its simple and convenient construction. At present, the research on steel support system has been by using the traditional theory and numerical simulation technology;however, these methods have a higher demand for the basic parameters of the model. Under normal circumstances, it is difficult to obtain these parameters. The artificial neural network has a strong learning, Lenovo and anti-jamming capability, and has shown great advantage in the prediction analysis. Based on a deep excavation of Qingdao subway station, through analyzing the monitoring data of steel strut axial forces, it gets influencing factors of the change of the axial force. At last, evaluation index system is established. Through predicting steel strut axial forces based on artificial neural network, the result shows that the forecast data has a good agreement with the measured data.

  1. Imitation modeling of ice dams (case study of Tom’ River, Western Siberia

    Directory of Open Access Journals (Sweden)

    V. A. Zemtsov

    2014-01-01

    Full Text Available The factors of ice jam formations in the lower flow of the Tom River (Siberia are investigated. A length of the main channel under investigation is about 120 km. Approaches to solution of the problem of the jam formation control and, as a consequence, the jam induced floods are considered on the basis of the imitative computer modeling of stream dynamics and ice jams. The simulation makes it possible to analyze different scenarios of initial forcing and to predict reactions of the river bed system to the effects. On the basis of 1D models developed in the HEC-RAS 4.0 modeling system for the Tom River at the city of Tomsk we investigated a possibility of the ice jam localization, probability of which at different parts of river flow varies in time according to change of the river water discharge, stream hydraulics, and ice cover thickness. The 2D hydrodynamic model of the Tom River channel system in the SMS 9.2 modeling system has been developed. It allows simulating effects of ice jams located in different sections of the river flow on the run-off redistribution between the main channel and other river branches. It makes possible to estimate hazards and risks of ice jam floods and probable effects of ice jams on formation of the river channel system. As a result it becomes possible to regulate the safe spring ice transit through populated areas.Analysis of factors of the ice jam formations has demonstrated that due to increasing anthropogenic influence changes of hydro-meteorological and geomorphologic conditions lead to more frequent occurrence of jam floods for the last 25 years as compared to previous 40-year period. The imitative computer models are proposed to be used for planning anti-jam measures since they make possible to create a whole system of the channel structure, a relief of channel and floodplain, a flow velocity field including dangerous hydrologic processes. Similar system would allow predicting both consequences of local

  2. A Calculation Method of Burst Height of Ballistic Missile Based on Radar Seeker%一种基于雷达导引头的弹道导弹爆高解算方法

    Institute of Scientific and Technical Information of China (English)

    郑宗贵; 王继平; 林红斌; 解静

    2014-01-01

    目前弹道导弹主要通过无线电引信测高来进行战斗部爆高控制,但弹头的再入环境对无线电引信测高装置的要求非常高,且引信存在着易被干扰的问题。为此,该文针对采用雷达景象匹配末制导的弹道导弹,提出一种基于雷达导引头的弹道导弹爆高控制方法,通过雷达导引头测高数据与惯性导航数据的融合处理,实时计算弹头飞行高程,来实现爆高控制,既保证了精度,又增强了抗干扰能力。仿真算例证明了该方法的有效性和爆高解算精度。%At present the height of the warhead of ballistic missile is measured by the radio fuze for the burst height control of the warhead, but the reentry environment of the warhead has very high requirement for the measure set of the radio fuze, and there exists the issue of the radio fuze to be jammed. In the paper, for the ballistic missile adopting the radar scene matching terminal guidance, a calculation method of burst height of ballistic missile based on radar seeker is put forward, by fusing the height measure data of the scene matching radar seeker and the inertial navigation data, the height of the warhead is calculated in real time to realize the burst height control, which ensures the precision and improves anti-jamming capability. The validity of the method and the calculation precision of the burst height are proved by simulation and calculation.

  3. 一种陀螺稳定平台自适应模糊-PID复合控制方法%Adaptive fuzzy-PID hybrid control method of gyro stabilized platform

    Institute of Scientific and Technical Information of China (English)

    朱倚娴; 陆源; 许江宁; 程向红

    2014-01-01

    机械摩擦、器件工作饱和区等不确定因素会导致陀螺稳定平台系统参数的波动和非线性特性,为解决非线性因素对稳定平台控制系统性能的影响,提出了一种自适应模糊-PID复合控制方法。引入自适应因子δ实现模糊控制和PID控制的复合,误差较大时增强模糊控制的作用以加快系统响应,误差较小时增强PID控制的作用以实现无静差调节。采用自调整量化因子ker(er)、kec(ec)实现基本论域的在线调整,提高了模糊控制器的灵敏度。仿真结果表明,在干扰冲击和短时常值干扰情况下,自适应模糊-PID复合控制与常规模糊控制相比,抗干扰能力显著增强,平台稳定精度提高0.4'左右。%System parameters of gyro stabilized platform are unpredictable because of the uncertainty factors such as mechanical friction, the saturation characteristic of the driver module, etc. To suppress the error caused by the nonlinear characteristics, an adaptive fuzzy-PID hybrid control method is proposed. The adaptive factorδis set up to combine fuzzy control and PID control. When the large attitude error of the platform is detected, the effect of fuzzy control is enhanced to decrease the system response time. And the conventional PID control effect is enhanced to eliminate the static error when the attitude error is small. Self-adjusting quantitative factors ker(er) andkec(ec) are proposed to adjust the basic domain of the fuzzy controller online, which improves the sensitivity of the control loop. The simulation results show that, in both cases of pulse and step interference,theadaptive fuzzy-PID hybrid control can improve the accuracy of platform attitude about 0.4 arc min and enhance its capability of anti-jamming compared to ordinary fuzzy control.

  4. A computational method of touch point coordinate%一种触摸坐标计算方法

    Institute of Scientific and Technical Information of China (English)

    胡跃辉; 刘志民; 吕国强; 李小哲; 于芳芳; 丁小宇

    2015-01-01

    近年来,随着多点触摸发展的日益多元化,触摸屏的结构日趋复杂,触摸算法日渐新颖。提出了一种触摸坐标点计算的新方法,将其称为“投壶”算法,意为将满足条件的物体准确投入壶中,此时壶里的权重增加,最后将权重最大的壶视为“真实”即为有触摸点的。实验证明,此算法能够在硬件资源有限的条件下,准确的计算触摸点的坐标,尤其在多点触摸的情况下,能够有效的避免伪触摸点的出现,具备一定的抗干扰能力,具有响应速度快、计算精度高等特点,实现触摸屏的无驱安装。%In recent years, with the development of multi-touch diverse, the structure of the touch screen is more and more complex, the touch algorithm is increasingly fashionable.This paper proposes a new method of calculating the touch point, which is called “pitch pot” algorithm.It means that we will put the object which meets the condi-tions into the pot, by this time the pot’s weight is adding.At last, the heaviest pot is looked as the real pot which means it has the touch point right now .The experimental results show that , under the circumstance of limited hard-ware resources, this algorithm can accurately calculate the coordinates of the touch point, especially in the case of multi-touch.It could effectively eliminate the false touch point, has a certain anti-jamming capability fast response and high accuracy, and achieves no driver installation.

  5. Automation Reconstruction of Shenbao Coal Surface Production System%神宝煤矿地面生产系统的自动化设计

    Institute of Scientific and Technical Information of China (English)

    张国军; 苏珂嘉; 付衍斌; 饶熊舟

    2013-01-01

    The design of technical research of the automation of centralized control system of Shenbao coal 10 million tons of ground production system includes a variety of equipments for the initiation, parking, protection, adopt the automatic and manual and on-site three control methods. This design program uses Siemens S7- 414H PLC modular design thought, through the Profibus-DP connect S7-414H and each branch. Makes full use of the touch screen control, the relative centralization system control of all focused on the touch screen, it is easy to operate, and can also display the main equipment status. Fully considering the anti - jamming ability of the system, and take various measures to improve the system stability. The design scheme realized the high automation system, enhanced the production efficiency.%神宝煤矿地面1 000万t生产系统全自动化集中控制系统的技术研发设计包括多种设备的启动、停车、保护,采用自动、手动和就地3种控制方式.该设计方案运用西门子S7-414H PLC的模块化设计思想,通过Profibus-DP总线将S7-414H与各分站连接起来.充分利用触摸屏控制,将系统的相对集中控制全部集中于触摸屏,便于操作,同时还可显示主要设备的运行状况.充分考虑系统的抗干扰性能,采取多种方式提高系统稳定性.该设计方案实现了系统的高度自动化,大大提高了生产效率.

  6. 表面增强拉曼散射基底的研究进展%Review on surface enhanced Raman scattering substrates

    Institute of Scientific and Technical Information of China (English)

    薛向欣; 许东铎; 常立民

    2015-01-01

    表面增强拉曼光谱(SERS)由于其高的灵敏度、抗干扰能力强等优点,被广泛应用在表面科学、分析化学、物理学等领域,是研究表面和界面过程的重要工具,是定性鉴定化学组成相近化合物的有力手段。因此,高品质、高活性的SERS基底一直是科研工作者们追求和研究的重点。本文对SERS活性基底的发展进行了介绍,从金、银金属纳米粒子作为基底的拉曼效应的科学研究,又进一步总结了非金属纳米粒子ZnO、TiO2、ZnS、Cu2O、CdTe、CdS等SERS基底。今后,将贵金属与半导体纳米材料复合将是SERS基底的研究热点。SERS光谱目前可以在液相色谱分析的检测器、医学检测仪器、刑侦分析检测等众多领域得到应用。%Due to its high sensitivity and strong anti-jamming ability,surface-enhanced Raman spectroscopy (SERS) is widely used in surface science,analytical chemistry,physics and other fields, and is a powerful tool for qualitative identification of compounds with similar chemical composition. Therefore,SERS substrates with high-quality and high-activity have always been a focus of researchers. Gold and silver metallic nano-particles based on the Raman effect were first introduced; and non-metallic nanoparticle,ZnO,TiO2,ZnS,Cu2O,CdTe,CdS etc,as surface-enhanced Raman substrate were then summarized in terms of the SERS signal enhancement. Surface-enhanced Roman spectroscopic is currently applied in the liquid phase chromatographic detectors,medical instrumentation,forensic analysis and testing,and many other fields. In the future,the substrates of the complex of metal/semiconductor materials shall be focused on.

  7. Performance analysis of QC-LDPC Codes in the chaotic DSSS for NBJ suppression%QC-LDPC码在混沌DSSS-NBJ抑制中的性能分析

    Institute of Scientific and Technical Information of China (English)

    李思佳; 毛玉泉; 李波; 裴鑫; 吴崇虎

    2013-01-01

    以低信噪比窄带干扰条件下混沌DSSS系统信息传输的可靠性提高为目的,在混沌DSSS系统的基础上,结合QC-LDPC码提出了一种基于QC-LDPC-CDSSS的协同窄带干扰(Narrowband Jamming,NBJ)抑制方案.该方案在直积构造方法生成校验矩阵的过程中,完成了校验矩阵4、6短环的检验与消除,采用近似下三角算法实现了QC-LDPC编码;对于混沌直序扩频系统,分析了组合混沌映射序列的性能和优选方法,采用优选的组合混沌扩频序列增强低截获能力;最后通过不同干扰条件下的仿真验证了该方案的有效性,仿真结果表明,该方案对于单音干扰的抑制效果优于多音干扰的抑制效果,在10-5的误码要求条件下,信噪比小于4dB.%In order to improve the bit-error-rate (BER) at the low SNR,a novel cooperative anti-jamming scheme for narrow-band jamming suppression is proposed based on the QC-LDPC codes and-integrated Map chaotic direct sequence spread spectrum.The QC-LDPC codes are designed through approximate lower triangular form algorithm based on the parity check matrix.The direct product is used for constructing the parity check matrix.The performance of chaotic spread spectrum sequences,produced from the integrated Chaotic MAP,is analyzed and their optimized selection algorithm is proposed.Finally,the strategy is verified through simulations with different jamming.The results show that the scheme performs better with single tone jamming than multi-tone jamming and the SNR is smaller than 4dB when the BER is 10-5.

  8. 机载GNSS掩星观测反演大气折射率廓线研究%Profiling the Atmosphere Refractivity Using the Airborne GNSS Radio Occultation Sounding

    Institute of Scientific and Technical Information of China (English)

    李潇; 张训械; 李烨; 王烁; 李兴国; 吕铁军

    2011-01-01

    作为星载掩星技术的推广,基于飞机平台的无线电掩星技术备受关注.为了将机载掩星技术更好地应用到工程实践中,文章通过介绍机载掩星探测的基本原理和主要特点、模拟仿真,对机载掩星的反演算法进行了探讨,并给出模拟结果:包括利用STK仿真软件生成仿真场景;采用3维射线追踪技术模拟机载无线电掩星,预报掩星事件出现的时间、仰角,模拟信号传播特征;详细研究大气层内折射率反演技术并给出反演结果.研究结果表明,模拟仿真对机载掩星工程化实现是有益的.最后展望了机载掩星探测的发展趋势,提出了弱掩星信号的捕获跟踪、飞机平台的精度定位测速以及反射信号的抗干扰三项技术及工程化中需解决的技术难点.%As an extended technique of GNSS radio occultation (RO), the airborne RO sounding has attracted much wider attention. In order to apply it in practical engineering, this paper firstly introduces some keystone and main features of airborne RO sounding. Then the simulation of the refractivity reversed is done and the reversed results are presented, including: establishing simulated scene by STK software; simulating airborne RO by 3D radial tracing technique to predict occultation occurring time, elevation and signal propagation feature; investigating refractivity reversed technique within the atmosphere. The simulated result is useful to airborne RO engineering. Some conclusions and prospect of airborne RO sounding are discussed. Finally, the paper points out that three technical difficulties in application are tracking weak RO signal, precisely measuring speed of airborne, and anti-jamming of reflection.

  9. 汽车防追尾无线动态测距系统的研究与应用%Research and Application of Wireless Dynamic Ranging System for Vehicle Anti-collision

    Institute of Scientific and Technical Information of China (English)

    王晓利

    2011-01-01

    In order to solve effectively the problem of dynamic distance-measuring on moving vehicle, this paper discusses the general design scheme based on dynamic distance-measuring system for moving vehicle. This paper uses ultrasonic wave propagation reflex obstacles principle in the air, and ultrasonic probe as interface unit, AT89S8252 single-chip microcomputer as core to calculate the ultrasonic transmission time in the air, and convert it to the corresponding distance to realize dynamic ranging. Through hardware design, it can realize real-time display for the distance between the car and the adjacent car. It can realize sound and light a-larm if the distance is too close. After the software programming and simulation, the results show that hardware and software design of the system is reasonable, anti-jamming ability is powerful, real-time performance is good, and it is of high precision. Through expansion and promotion, the system can be widely used in different ranging occasions with its high ratio of performance and cost.%为了有效解决汽车行驶中的动态测距问题,讨论汽车动态测距系统的总体设计方案,利用超声波在空气中传播遇障碍物反射原理,以超声波探头为接口部件,AT89S8252单片机为核心,计算超声波在空气中传播的时间,并换算成对应的距离来实现动态测距,通过硬件设计实现自车和邻车之间距离的实时显示和非安全距离的声光报警.经软件编程仿真,结果表明该系统软硬件设计合理、抗干扰能力强、实时性良好、精确度较高.经过系统扩展和升级,以其较高的性价比可在不同的测距场合得到广泛应用.

  10. Robustness Analysis of LSB Image Hiding Algorithm Enhanced by Chaotic Sequence%混沌序列增强LSB图像隐藏算法的鲁棒性分析

    Institute of Scientific and Technical Information of China (English)

    张艳玲; 王允锋

    2015-01-01

    For the high security requirement of image ,a new image hiding algorithm based on chaos and LSB is proposed to eliminate the defect of LSB image hiding algorithm ,in w hich the hidden image is easy to be cracked . Making full use of human visual characteristics of redundancy , according to the randomness of chaotic sequences ,6 corresponding integer random sequences are generated w hich decide the row s and columns of R and G and B components of the embedded point of carrier image .Finally ,the secret image information is embedded into the lowest point of the embedded point of carrier image in order to hide the secret image information .T he random selection of embedded points enhances the shear resistance of the algorithm .Experiments show that the algorithm enhances the anti-jamming ability of the image ,has good robustness against the noise attack and the shear attack ,and its robustness and invisibility are better than that of the traditional LSB algorithm .%为消除最不显著位(LSB)图像隐藏算法隐藏图像易被还原的缺陷,基于图像的高保密要求,提出了一种混沌和LSB相结合的图像隐藏算法。利用人眼视觉冗余特性,根据混沌序列的随机性,生成了6个整数随机序列。依次对应载体图像嵌入点 R、G、B三个分量的行列坐标,通过秘密图像随机地嵌入到载体图像嵌入点的最低位中,实现了秘密图像信息的隐藏。实验结果表明:混沌增强LSB数字图像隐藏算法增强了图像隐藏的抗干扰能力,其鲁棒性和不可见性优于传统LSB算法,对噪声攻击和剪切攻击具有良好的鲁棒性。

  11. Study of Fuzzy Adaptive PID Control of Brushless DC Motor%无刷直流电机模糊自适应PID控制的研究

    Institute of Scientific and Technical Information of China (English)

    潘晓磊; 赵川; 吕海立

    2016-01-01

    为了提高无刷直流电机控制系统的动、静态性能,将模糊控制结合PID控制算法应用到无刷直流电机速度控制系统中。在分析了无刷直流电机速度控制系统的基础上,利用PSIM与MATLAB/Simulink共同建立了无刷直流电动机模糊自适应PID控制的仿真模型,充分发挥了PSIM和MATLAB/Simulink各自在仿真方面的优势,简化了建立仿真模型的过程。仿真结果表明,采用模糊PID集成控制算法能够使无刷直流电机速度控制系统具有更快的响应速度和更强的抗干扰能力,对无刷直流电机控制系统的设计具有一定的指导意义。%In order to improve the static and dynamic performance of brushless DC motor control system, fuzzy control combined with PID control algorithm is applied to the brushless DC motor speed control system, the integration of fuzzy PID control algorithm. On the analysis of the brushless dc motor speed control system, using the MATLAB/Simulink to establish brushless DC motor speed control system simulation model. Among them, the control system of brushless DC motor drive model and control algorithm were established in PSIM and MATLAB/Simulink environment, give full play to their advantages, the PSIM and MATLAB simplifies the process of establishing simulation model. The simulation results show that the integration of fuzzy PID control algorithm can make the brushless DC motor speed control system has better dynamic and static performance and strong anti-jamming capability, the design of brushless DC motor control system has a certain guiding significance.

  12. 基于多水质参数融合的锅炉连排复合控制%Compound ControI of BoiIer Continuous BIowdown Based on MuItipIe Water QuaIity Parameters

    Institute of Scientific and Technical Information of China (English)

    王恭; 周晓东; 张腾宇; 赵鑫岩; 王冰礁; 曹生现

    2015-01-01

    Aiming at the difficulty in rational control over the continuous blowdown’s flow of the power plant boiler,the feed forward-feedback control system based on the boiler water’s quality parameters was designed. In its feed forward control,the system makes use of the data fusion algorithm to associate the water quality pa-rameters (pH,conductivity,phosphate ions,silica dioxide)with the continuous sewage flux so as to eliminate the influence of both multivariable and large time delay;in its feedback control,the self-tuning PID control employed can improve the system’s anti-jamming capability and tackle time variation.The simulation results show that the system overshoot can be controlled at 10.5% and the adjusting time can be shortened by nearly 79s in normal operating condition so as to improve the system’s dynamic and static traceability.%针对电厂锅炉连续排污过程中连排流量难以合理控制的特点,设计了基于炉水多水质参数的前馈-反馈控制系统。该系统在前馈环节利用数据融合算法,将炉水水质参数(pH 值、电导率、磷酸根离子、二氧化硅)与连排流量进行关联,以克服多变量及大迟延等特点的影响;反馈环节利用模糊自整定PID 控制,提升系统的抗干扰能力,解决时变性问题。控制系统仿真结果表明:在机组正常运行条件下,该系统可将系统超调量控制在10.5%,调节时间缩短近79s,提升了系统的动静态跟踪能力。

  13. Design of measurement substation in coal monitoring system%煤炭产量监测系统中计量分站的设计

    Institute of Scientific and Technical Information of China (English)

    王亚姣; 郝伟栋; 马丰杰

    2011-01-01

    In order to accord with the design requirements of the coal monitoring system, monitor the coal output of coal mine in real-time, the measurement substation was developed that combined electrical design and explosion-proof technology. The measurement substation contains that the frequency acquisition based on the phase schmidt triggers designed by LM2903, the passive contact type digital acquisition based on TLP421,design of the low error rate based on ASCII code mode used in the MODEM transmission.The paper focuses on the design and package of safety barrier, casting,and the layout design and test of the intrinsically safe circuits.The test result of National Explosion-proof Organization shows that the measurement substation complies with procedures.ln addition, the measurement substation shows stable performance, good anti-jamming performance and explosion-proof effectively, accord with the design requirement of the intrinsically safe system.%为了符合煤炭产量监测系统的设计要求,实时监测矿井出煤量,开发了将电气设计和防爆技术相结合的计量分站.介绍了计量分站以LM2903构建的反相施密特触发器为基础的频率采集电路和以TLP421为基础设计的无源触点型开关量采集电路,以及MODERN传输方式采用的基于ASCⅡ编码方式的低误码率数据帧设计方法,重点介绍了计量分站中齐纳式安全栅的设计、灌封和本质安全电路的布线要求和评定方法.国家检验机构检验结果表明.计量分站性能稳定、抗干扰性能好,能够有效实现防爆,符合本安系统的设计要求.

  14. Application and Estimation of LS Code in Underwater Acoustic Spread-spectrum Communication%LS码在水声扩频中的应用及估计

    Institute of Scientific and Technical Information of China (English)

    张帅; 高勇

    2013-01-01

    The further application of underwater acoustic spread-spectrum communication system is limited by multipath interference, so the choice of spread spectrum sequences with better performances can im-prove the anti-jamming performances of underwater acoustic spread spectrum system. Based on discussion of LS code properties, LS codes is proposed for underwater acoustic spread-spectrum communication ,and the superiority of its application also analyzed in this paper. Simulation on rayleigh channel model of un-derwater acoustic indicates good performances of the spread-spectrum communication based on LS code. With power- spectrum processing and singular value decomposition, the spread spectrum sequence of un-derwater acoustic spread-spectrum signal based on LS code is estimated. The simulation results shows that with this method,the LS code can be estimated correctly in the condition of SNR=-11 dB.%水声多径干扰限制了水声直接扩频通信系统的进一步应用,选取性能更好的扩频序列可以提高水声扩频系统的抗干扰性能。在讨论了LS码特性的基础上,提出了将LS码应用于水声直接扩频通信中,并分析了LS码应用的优势。通过多径瑞利水声信道模型仿真,验证了LS码水声扩频通信的良好性能。利用了二次谱和奇异值分解的方法对LS码水声直扩信号的扩频序列进行了估计。仿真结果表明,该方法在信噪比为-11 dB 时还能准确的估计出LS码。

  15. Application of Metamaterials to the Optimization of Smart Antenna Systems

    Science.gov (United States)

    Allen, Jeffery Wayne

    Recent developments in engineered electromagnetic materials called metamaterials have opened the door to a whole new class of devices and improved performance in existing systems using electromagnetic properties that are beyond those found in nature. These materials can be designed to have spatially varying anisotropic electromagnetic properties which include positive and negative permeability and permittivity values. The objective of this research was to explore how these newly available degrees of freedom in material parameters can be exploited to improve the performance of smart antenna systems. In this dissertation, we examined adaptive null/beam forming phased array systems in the presence of metamaterial superstrates. While these systems have been studied extensively from a system engineering point-of-view, understanding the system from a material engineering prospective will help define the role that these new materials can play in these systems and how they maybe designed to enhance the overall system performance. One specific area further explored is how to steer the available performance of these systems, preferentially to regions of the scan space where interferers/jammers are most likely to occur, thus improving the system's anti-jamming or interference mitigation capabilities. New performance gains can also be suggested by including the behavior of sources and accompanying material properties in the transformations optics methodology to modify space through material design. This can be achieved using source transformations. Chapter 1 introduces the basic theory of phased array systems and radomes, background of previous work carried out, Controlled Radiation Pattern Antennas, Global Position Systems and a short overview of transformation optics and metamaterials. In Chapter 2, we present analytical, ray tracing and full-wave electromagnetic simulation models to analyze the effect of a quasi-optical element on the array performance. We use these models

  16. Design for Infrared Imaging Seeker Controller Based on Auto Disturbance Rejection Control%基于自抗扰技术的红外成像导引头控制器设计

    Institute of Scientific and Technical Information of China (English)

    栗金平; 杨军; 凡国龙

    2011-01-01

    研究导弹的红外精确制导问题.红外成像导引头具有抗干扰能力强、制导精度高、全天时工作以及可进行自动目标识别等特点.由于弹体的姿态扰动会造成红外成像导引头成像模糊,为隔离弹体姿态扰动对成像的影响,加强稳定性控制,提出采用自抗扰控制技术设计红外成像导引头稳定回路控制器.首先,在完成红外成像导引头稳定回路数学建模的基础上,采用扩张状态观测器对受扰后对象的状态和干扰进行估计.然后,采用非线性状态反馈,并对估计的干扰进行补偿,从而实现对指令的精确跟踪,并通过红外成像导引头稳定回路的仿真证明了所设计的自抗扰控制器具有很强的隔离姿态扰动的能力,表明设计方法有效性.%Infrared imaging guidance has better anti -jamming capability and excellent guidance accuracy, and it can work full time and track target automatically, so it is one of the key researches of every country. The disturbance of body can lead the poor seeker imaging. In order to reduce the effect, we design its controller with auto disturbance rejection. First, based on the object mode, we estimate the system state and the disturbance through the extended state observer. Then, we feedback the state error nonlinearly and compensate the disturbance in order to track the dictate accurately. Finally ,the simulation of the control system designed in this paper shows that the control system has excellent performance to eliminate the disturbance.

  17. Research progress of automatic navigation technology for orchard mobile robot%移动机器人自动导航技术研究进展

    Institute of Scientific and Technical Information of China (English)

    蒋浩然; 陈军; 王虎; 雷王利; 袁池

    2011-01-01

    针对目前果园移动机器人自动导航技术研究现状,综合分析现有的有关文献,依据环境感知方式的不同,分别讨论了以激光、视觉、机械、电磁、GPS、超声波为感知系统的导航方法的研究进展,分析了现有几种导航方法在精度、实时性、抗干扰能力及系统适应性等方面的优缺点,认为多传感器融合技术可为果园移动机器人的导航提供更高的精度和稳定性。在此基础上,提出了未来果园移动机器人自动导航技术的发展趋势,即多传感器融合技术是果园移动机器人感知环境的主要手段,满足果园移动机器人精度和稳定性要求的导航系统将是今后研究的重点。%The existing related literatures were analyzed based on the current research progress of the orchard mobile robot's automatic navigation technology.According to the different environmental perception methods,the current research status of the navigation methods with perception systems based on laser,vision,machinery,electromagnetism,ultrasonic and GPS were discussed respectively;the advantages and disadvantages of each method in terms of navigation accuracy,real time,anti-jamming capability and the flexibility of the system were also discussed.Then we believe that the multi-sensor fusion technology could provide higher precision and stability for the orchard mobile robots' automatic navigation.On that basis,this paper proposed the development tendency of automatic navigation technology for orchard mobile robot in the future,multi-sensor fusion technology would become the main method of the environment perception for orchard mobile robot.Therefore,the development of the navigation system with required accuracy and stability for the orchard mobile robot would be the emphasis of the future research.

  18. 水下重力异常相关极值匹配算法%Correlative Extremum Matching Algorithm Using Underwater Gravity Anomalies

    Institute of Scientific and Technical Information of China (English)

    李姗姗; 吴晓平; 马彪

    2011-01-01

    Gravity-aided inertial navigation is a technique that makes use of gravity to correct inertial navigation error of underwater vehicles.Matching algorithm is vital in the process of gravity-aided inertial navigation.An object function model of differential descending weight-correlation was put forward based on the principle of mean square deviation.Because of the influence of random errors,there are multi-available positions determined by the object function model which are around the real position with different probabilities.Then,a probabilistic data association filter(PDAF) algorithm was proposed.Navigation position determined by PDAF is much closer to the actual one than that chosen by the nearest neighbor method,the reliability and the anti-jamming of the algorithm are improved.Then,the effect of the serial sampling intervals on the matching precision was discussed.Through simulations in the experimental area,the results showed that navigation errors were corrected effectively with proper sampling intervals and sampling lengths based on the algorithm.%重力辅助惯性导航是利用地球物理特征信息——重力来修正水下潜器惯性导航误差,其关键技术是匹配算法。基于平均平方差最小准则构造差分降权相关目标函数模型,针对受干扰误差随机影响,基于目标函数模型搜索得到的多个有效位置,均有可能以不同概率密度源于正确位置这一问题,提出概率数据关联滤波重力匹配算法,与最近邻法相比,该算法确定的航迹更接近于真实位置,提高算法的可靠性与抗干扰性;分析探讨序列采样间隔对匹配精度的影响。通过试验区仿真匹配,结果表明,当选择适当的采样间隔与采样长度,该算法能有效修正导航误差。

  19. GPS P码接收机本地信号发生器的FPGA实现%Implementation of Local GPS P Code Generation in GPS Receiver Based on FPGA

    Institute of Scientific and Technical Information of China (English)

    曹进; 李荣冰; 徐昭; 谢非

    2013-01-01

    As the military use of GPS,P code is famous for its characteristic of high precise,long period and complex structure. The software receiver based on P code is not only of high position precision, but also of high level of anti-jamming and anti-spoofing. It is of great importance for direct P code acquisition and the tracking if we can generate any bits of P Code in its period. After doing research on the mechanism and structure of P Code generation, we designed some algorithm of P code and realize it through MATLAB. Then we propose the algorithm for FPGA by modules including register module, delay module,period module and register phase module. The result shows that P Code of any time or any satellite can be generated by it without time delay.%P码作为GPS军用伪码,具有结构复杂、周期长且码速率快的特点,这使得使用P码的软件接收机不仅定位精度高,且具有很强的抗干扰和反欺骗能力.能够实现任意卫星的任意时刻P码的产生,对于实现P码直接捕获和跟踪有很重要的意义.对于P码的产生原理和结构进行了分析,基于MATLAB设计了相应的P码发生算法并进行简单的算法仿真.之后针对FPGA硬件平台对P码发生器进行了相应的模块设计,包含寄存器模块、延时模块、周期控制模块和寄存器相位模块等.测试实验结果表明P码发生器可以基本无延迟地生成任意卫星、任意时刻的P码.

  20. Judgement of Direction of Movement Based on Active RFID%基于有源RFID的运动方向判断

    Institute of Scientific and Technical Information of China (English)

    喻剑; 杨卫

    2011-01-01

    RFID is one of the crucial technology of the IOT (Internet of things) , and it has been applied to the fields of manufacture, logistics, public security, and etc. Active RFID is one of RFID, and the striking features of active RFID are low power consumption, stable signals, long-distance reading and anti-jamming ability. Therefore, active RFID is widely used in the areas of long-range identification of personnel and vehicles and Real Time Location System. In the various application of active RFID, the judgement of direction of movement is a vital technical matter. A new method is put forward to judge. In other words, with several directional antennas, it forms several reading areas, picks up events of the tag entering or exiting and then realizes the judgement of direction by the order of events. In this way, I could not only judge the direction of movement of tags accurately, but also judge other complicated logic, e. g. the midway return of tags.%RFID技术是物联网相关的重要技术之一,已经在生产制造、物流管理、公共安全等众多领域得到了应用.有源RFID技术是RFID技术的一种,具有低功耗、信号稳定、读取距离远、抗干扰性能好等特点,被广泛地应用于车辆、人员的远距离标识与RTLS定位等.在有源RFID各种应用中,对于标签运动方向的判断是一个重要的技术问题.提出一种使用多个定向天线读写设备,形成多个读取区域,提取标签在各区域中的事件,通过事件逻辑顺序实现对运动方向的判断.采用这种方法不但可以准确判断标签运动方向,而且可以判断标签中途返回等一些复杂逻辑.

  1. Study on Polarization Spectral Feature of Suspended Sediment in the Water Body%水体悬浮泥沙的偏振光谱特性研究

    Institute of Scientific and Technical Information of China (English)

    朱进; 王先华; 潘邦龙

    2012-01-01

    Remote sensing of lake water based on water-leaving radiance is to retrieve the concentrations of suspended sediment, phytoplankton and yellow substance which have great impacts on spectrum to assess the water quality. Howerver, because of the complexity of the lake water compositons and the interference between the different components, it is of great difficulty to get accurate results with the reflectance spectrum method developed recently. In the present paper, the authors firstly discussed the reflectance and polarization spectral feature of suspended sediment water body, found out the relations of the reflectance and the degree of polarization of water-leaving radiance and the concentration of suspended sediment at the sensitive bands. The authors also compared the effectiveness of the retrieval approaches based on reflectance and polarization in laboratory water body and Chaohu water body respectively. The results show that in the lake water body where the constituents are very complex, the polarization information has greater capacity of anti-jamming, therefore it will have great potential applictions in lake water quality remote sensing.%基于离水辐射的湖泊水体遥感通过反演与光谱关系密切的悬浮泥沙、浮游植物和黄色物质等要素的浓度来实现对水质状况的评估,然而由于湖泊水体的复杂性以及不同要素间的相互干扰,现有的基于反射率光谱的分析方法难以准确反演这些要素.从悬浮泥沙水体离水辐射的反射率、偏振光谱特性出发,给出敏感波段处悬浮泥沙浓度与反射率、偏振度之间的关系,比对了基于反射率以及基于偏振度的两种反演方法在实验室水体、巢湖水体中的应用效果.研究结果表明,在湖泊复杂水体条件下,水体的偏振信息具有比反射率更加良好的抗干扰能力,显示偏振度信息在湖泊水质遥感上存在着重要的应用潜力.

  2. Temperature field reconstruction based on Gaussian radial basis function with subarea optimization%基于高斯径向基的子区域优化温度场重建算法

    Institute of Scientific and Technical Information of China (English)

    柳丹; 石为人; 熊庆宇; 石欣

    2015-01-01

    In the application environment where measuring the temperature in the process of industrial heating,the reconstruc-tion algorithm is the key to realize the measurement of temperature field by using ultrasonic.In order to solve the problem,this paper developed a reconstruction optimization algorithm without changing the number of effective ultrasonic wave.It used the perfect function approximation ability of Gaussian radial basis function to implement the mapping relations between the sound wave propagation velocity and the temperature distribution,then reconstructed the measured temperature field through the ma-trix singular value decomposition.The algorithm had reconstructed four kinds of typical model of temperature field:unimodal skewed,unimodal symmetric,bimodal deflection and bimodal symmetrical under different Gaussian noise interference in the simulation experiments.The simulation results have proved that the algorithm has the advantages of high reconstruction preci-sion,strong anti-jamming capability and fast response speed.%在采用超声波进行工业加热过程中的温度场测量时,重建算法是实现被测温度场重建的关键。针对这一问题,提出一种基于高斯径向基函数的子区域优化温度场重建算法,不改变有效声线数,细化子区域,运用高斯径向基函数,逼近超声波传播速度与温度分布的映射关系,通过矩阵奇异值分解重建被测温度场。针对单峰偏斜/对称、双峰偏斜/对称四种典型模型温度场,在不同高斯噪声干扰下进行温度场重建仿真实验,结果表明:该算法重建精度高、抗干扰能力强、响应速度快。

  3. 步进式加热炉自动控制系统设计%The Design of Walking Beam Furnace Automatic Control System

    Institute of Scientific and Technical Information of China (English)

    解韶峰; 崔桂梅; 李爱莲

    2014-01-01

    本文针对包钢无缝厂ȼ180机组步进式加热炉进行自动控制改造。步进式加热炉自动控制系统包括物料传输控制系统和加热工艺过程控制系统两部分,前者以开关量为主,多属于电气控制;后者以模拟量为主,属于过程控制。论文构建了基于现场总线的网络化系统方案,并进行了具体的软硬件设计工作,对炉膛温度采取了模糊串级双交叉控制策略,增强了系统的稳定性和抗干扰的能力,且电气和过程控制共用一套PLC,大大节约了硬件建设的成本。%The thesis discusses automatic control's reform in allusion to the walking beam furnace in plant unit ȼ180 of Baotou steel seamless factory.walking beam furnace Automatic Control System includes two parts of material transmission control system and the heating process control system.The former gives priority to switching value,and most of it belongs to electrical control.The latter gives priority to analog quantity,belongs to process control.Paper structures networked system solutions based on profibus,and has carried on specific work on soft-hardware design.takes the way of fuzzy series double-crossing control about FBT(furnace box temperature).The system stability and anti-jamming capability enhanced largely.Besides the electrical control and process control share one set of PLC,so that the cost of hardware construction was saved greatly.

  4. 高精度动载体激光发射系统光束控制反射镜%High performance fast-steering mirror for beam control of vehicular high energy laser system

    Institute of Scientific and Technical Information of China (English)

    王恒坤; 张国玉; 郭立红; 刘廷霞; 王兵; 郭汝海

    2013-01-01

    A Fast Steering Mirror (FSM) suitable for motion environments was designed to control the laser beam stabilization and its accurate alignment for a laser projecting system in the vibration and shocking. According to the requirement of performance of the optical system, the necessary physical and mechanical characteristics of the FSM were presented for the reflecting mirror of a high energy laser. The voice coil actuators with large travels were used as the drivers of the FSM, and angle displacement measuring devices with high precision and anti-jamming ability were taken as the position sensors of the FSM. The four voice coil actuators and four angle position measuring devices were reasonably arranged to decrease the inertial moment of the system and also to improve the reliability and condition adaptability. The experimental result shows that the positioning accuracy of FSM is better than 1.4, which satisfies the precision requirement of the laser projecting system for the FSM.%设计了一种适于车载等运动环境下的快速控制反射镜,用于在具有振动和冲击的工作环境下控制激光发射系统的激光光束稳定及其精确校准.根据某光学系统的性能指标要求,阐述了用于高能激光的平面反射镜的物理性能以及控制反射镜负载应有的机械特性.采用大行程的音圈电机作为控制反射镜的驱动器,并设计了精度高、抗干扰能力强的角位移测量装置作为控制反射镜的位置传感器.对所采用的4个音圈电机和4个角位移测量装置进行了合理布局,既降低了系统的转动惯量又提高了系统的可靠性和环境适应性.实验结果表明:该快速控制反射镜的定位精度优于1.4″,满足高能激光发射系统对控制反射镜的精度要求.

  5. SAVSTMV波束形成算法研究%Research on SAVSTMV beamforming algorithm

    Institute of Scientific and Technical Information of China (English)

    卢中新; 周胜增; 高源

    2014-01-01

    Conventional vector array beamforming (VCBF) is able to solve the notorious port-starboard (PS) ambiguity problem of the ordinary single linear array. But, the beamwidth of VCBF is restricted by Rayleigh limit, VCBF can not distinguish the multi-targets in the same beam. Vector array steered minimum variance (VSTMV) beamforming is a wideband adaptive beamforming method with high-resolution and anti-jamming capability. However, the VSTMV beamforming implemented in the element-domain causes heavy computational load and low robustness, so it is not suitable for real-time implementation and application in sonar engineering. In this paper, an algorithm of VSTMV beamforming implemented in the sub-array domain (called SAVSTMV beamforming) is proposed, with which the computational load can be reduced and the robustness improved. The better performance of SAVSTMV beamforming over VCBF is proved through theoretical analysis and simulation calculation, which makes the proposed algorithm suitable for practical applications.%矢量阵常规波束形成(Vector array Conventional BeamForming, VCBF)能够消除普通单线阵左右舷模糊现象,但VCBF波束宽度受到“瑞利限”的限制,不能分辨同一波束内的多个目标。矢量阵导向最小方差(Vector array STeered Minimum Variance, VSTMV)波束形成算法是一种宽带自适应波束形成算法,具有高分辨力和抗干扰性能。VSTMV波束形成直接在阵元域进行,计算量较大且稳健性差,不利于实时实现和应用。提出一种分子阵 VSTMV 波束形成算法(Sub-Array Vector array Steered Minimum Variance, SAVSTMV),可有效降低计算量,算法稳健性更强。通过理论研究和仿真计算,证明该算法比矢量阵常规波束形成算法具有更好的性能,有利于实际应用。

  6. A Study on the Integrated Electronic Control System of G asoline Engine%汽油机集中式电子控制系统的研究

    Institute of Scientific and Technical Information of China (English)

    段晖辉; 姜卓; 卓斌

    2001-01-01

    介绍了基于上海大众 M3.8.2系统研制出的新型汽油机集中式电子控制系统。该电子控制系统通过运用80C196单 片机和可编程系统器件PSD402A1实现了对汽油机的多点燃油顺序喷射控制、无分电盘电子点 火控制、怠速转速控制及空燃比闭环控制。试验结果表明,该电控系统不仅在硬件接口上与 原系统完全兼容,而且通过现场可编程系统器件的运用使得系统具有体积更小、可靠性和抗 干扰能力更强的特点。通过在上海大众AJR发动机上的标定试验表明,应用了本电控系统的 汽油机,其动力性、经济性和排放指标基本达到了原系统的水平。%This paper introduced a new integrated electroinic control system of gasolin e engine based on Shanghai Volkswagen (SVW) M3.8.2 control system.With the appli cation of a new electronic control unit (ECU) based on Intel's 80C196 microcont roller & WSI Co.'s field programmable system device PSD402A1,multi-ports sequen tial fuel injection (SFI) system,distributorless electronic ignition system,idle speed control system and A/F close-loop control system were developed.The expe riments show that the new system is not only compatible with M3.8.2 system,but a lso is smaller and has better anti-jamming ability with the help of field progr ammable system device.Through the calibration experiment on SVW 2VQS AJR gasolin e engine,the results show that under the control of the new Control System,the G asoline Engine's power performance,fuel economy and exhaust emissions recover to the former.This paper will discuss the control principle & strategy of every su b-control system and the experiment result with also be illustrated.

  7. 基于改进Otsu的室外道路实时检测与跟踪算法%Real-time Detection and Tracking of Road Information for Outdoor Vision-based Robot Based on Improved Otsu

    Institute of Scientific and Technical Information of China (English)

    陆培源; 王建中; 罗涛

    2011-01-01

    The detection and tracking of road infornmtion, are the basis and prerequisite of environmental exploration anti autonomous navigation ],y mobile robot. In view of the complexity of the ouldoor working environment of the robot and the variety of the outdoor illumination conditions, a suitable and novel way of real-time detection and tracking for outdoor robot is presented. First, the video images obtained from CCD camera are preprocessed. Then the Region of Interest (ROI) is extracted and transformed into the HSV color space. The edge information of the road image is obtained from the ROI by using the improved Otsu algorithm. With the anti-jamming ability of the Hough transform, the regiom where robot can pass through is shown. Finally the weighted Mahalanobis distance discrimination method is used to track the passing area. Experiment results show that this algorithm enjoys a good performance in the detection and tracking of road information in outdoor environment in real-lime.%室外道路检测与跟踪是移动机器人完成室外环境探索和自主导航的基础和前提.针对室外机器人工作环境复杂、光照多变等特点,提出了一种适用于室外道路实时检测与跟踪的算法.首先将CCD摄像头获得的画面通过预处理,提取视频画面的感兴趣区域(ROI)并转化为HSV颜色空间下的图像,然后通过改进的自适应阈值分割法(Otsu)获得道路图像的边缘信息,采用抗干扰能力较强的霍夫(Hough)变换得出画面中的可通行区域,最后采用加权马氏距离判别法跟踪可通行区域.实验表明,该算法在室外环境下具有较好的道路识别跟踪能力和实时性.

  8. GPS M码信号压制干扰样式效能分析%Effectiveness Analysis of the Blanket Jamming Mode to GPS M Code Signal

    Institute of Scientific and Technical Information of China (English)

    毛虎; 吴德伟; 卢虎; 白盟亮

    2015-01-01

    Aiming at the feature and superiority on anti-jamming of global position system (GPS) M code signal, in order to find an effective jamming mode for M code signal, the jamming efficiency of three types of typical blanket jamming, single frequency, band-limited Gaussian noise, and pseudo code with the same rate, are analyzed. In the analysis, the power spectral density change of GPS receiver cross-correlation filtering output is taken as the qualitative evaluation bases;the code tracking error and the ephemeris bit error rate (BER) are taken as the quantitative evaluation indexes. The influence process of jamming to evaluation factor and the oneness of each evaluation factor are derived theoretically by modeling M code signal receiving system. The simulation results show that single frequency jamming exhibits the best jamming effect while band-limited Gaussian noise jamming is the worst, the second comes pseudo code with the same rate jamming when the influence of sub-carrier modulation was eliminated. Considering the complexity of smart jamming implementation, it is suggested to choose the pseudo code with the same rate as M code signal jamming since single frequency jamming needs strict frequency setting and it is easily eliminated by frequency domain filtering.%针对GPS M码信号的特点和在抗干扰方面的优越性,为实现对其有效干扰,以接收机相关滤波输出功率谱变化情况作为定性评估依据,以码跟踪误差和星历误码率作为定量评估指标,对单频、带限高斯噪声和同速率伪码3种典型压制干扰样式的干扰效能进行分析。通过建立M码信号的接收系统模型,从理论上推导了干扰对各具体评估要素的影响过程以及各要素之间的统一性。仿真结果表明,单频干扰效果最好,消除副载波调制影响的同速率伪码干扰次之,带限高斯噪声干扰效果较差。考虑到单频干扰对干扰频偏设置的较高要求以及容易被接收

  9. 无线电/激光高度表复合测高技术研究%Research into Composite Altimetry Technology Based on Radio/Laser Altimeter

    Institute of Scientific and Technical Information of China (English)

    毕开波; 姚申茂; 谢春思

    2016-01-01

    无线电高度表和激光高度表是巡航导弹上用于探测地形高度的2种主要传感器,激光高度表具有探测精度高、抗电磁干扰能力强的优点;而无线电高度表不受天气和环境的影响,可全天候使用。因而,将无线电高度表与激光高度表进行复合探测,有利于提高地形探测精度,并增强系统抗干扰能力。在高度表测量方程的基础上,基于卡尔曼滤波公式和简单融合算法,给出了无线电/激光多传感器的滤波及融合模型;并利用M atlab对多传感器融合效果进行了仿真。仿真结果表明:基于多传感器融合的高度测量系统的精度比单个传感器的测量精度要高,且系统的稳定性和可靠性更强,所设计的基于无线电/激光高度表多传感器数据融合的高度测量算法是有效的。%Radio altimeter and laser altimeter are two main sensors which is applied to detect terrain altitude of the cruise missiles .Laser altimeter has high detection precision ,strong anti-electromag-netism-jamming ability .However radio altimeter can work under the condition of all-weather , which is immune for weather and environment .Detection system combining radio altimeter with la-ser altimeter can improve terrain detection precision and anti-jamming ability .On the basis of altim-eter measuring equation ,this paper presents radio/laser multi-sensor filtering model and fusion model based on Kalman filtering formula and simple fusion arithmetic ;simulates the fusion effect of multi-sensor by means of Matlab .The simulation results show that the altimetry system based on multi-sensor fusion has higher detection precision than single sensor ,and has good stability and re-liability ,the multi-sensor data fusion altimetry arithmetic based on radio altimeter/laser is effec-tive .

  10. 基于多尺度小波分解FDR的激光预警系统信息数据校正%Based on Multi-scale Wavelet Decomposition FDR Information and Data Correction for Laser Warning System

    Institute of Scientific and Technical Information of China (English)

    鲁旭涛; 李静; 杨泽辉

    2014-01-01

    significantly improved,significantly enhanced anti-jamming capability.

  11. Thrustor Control of Autonomous Underwater Vehichle Based on Artificial Immune Feedback%基于人工免疫反馈的自治水下机器人推力器控制

    Institute of Scientific and Technical Information of China (English)

    吴乃龙; 刘贵杰; 李思乐; 徐萌

    2011-01-01

    The thruster is the crucial factor of an underwater vehicle system, because its thrust modeling and control is the core of underwater vehicle control and simulation. With a view to the drawbacks of thrust real-time response and anti-jamming capability of simplified thruster control model of Autonomous underwater vehicle, an artificial immune feedback based thrust control method of thruster is presented. This method has a good real-time performance and robustness without the difficulty of carrying out hydro-dynamic experiment and theory calculation. It can provide methods for motion control, state response and control exploitation of AUV. Aimed at a streamlined AUV prototype named Cranger-2, the immune feedback mechanism is used to control the thrust of thrusters based on the analysis of the simplified thrust model by the creation of thrust real-time debugging system. Then the thrust output response curve is obtained according to different thrust input and interference signals through simulation analysis of thrust control. By the control and verification test of brushless DC motor, the result demonstrates that the method can control the thruster's thrust effectively and can provide a reference for engineering practice.%推力器是水下机器人系统的关键要素,其推力建模和控制是进行水下机器人控制和仿真的核心.针对简化的自治水下机器人(Autonomous underwater vehicle,AUV)推力器控制系统的推力响应实时性不高和抗干扰能力不强的缺点,提出一种基于人工免疫反馈的AUV推力控制方法,该方法不受推力器水动力试验和理论计算的困难性的缺点影响,具有较好的实时性和鲁棒性,可为AUV运动控制、状态响应、控制系统开发等提供控制方法.针对流线型AUV原型样机CRanger-2,在简化推力模型的分析基础上,利用该控制策略,建立推力实时调试系统,在不同大小推力和不同干扰情况下进行推力控制仿真分析,得到推力

  12. 周期性冲击对大型超导核聚变低温系统氦透平膨胀机影响研究%Study of periodicity impact of helium turbine of superconducting Tokamak device

    Institute of Scientific and Technical Information of China (English)

    付豹; 张启勇; 庄明; 朱平; 成安义

    2013-01-01

    超导核聚变装置磁体会因“交流损耗”而产生大量的热,迫使磁体内通道压力升高,导致与之直接相连的氦透平膨胀机的运行稳定性与运行效率受到严重影响,从而影响超导核聚变实验.详细分析超导核聚变装置用低温氦透平膨胀机受周期性冲击的机理与不可回避性,并用提高氦透平膨胀机本身性能、改善制动调节与氦透平膨胀机出口压力调节的反馈控制思想,得出一些提高氦透平膨胀机稳定性、降低冲击的方法.高效气体轴承与优化的转子结构可以有效提高氦透平膨胀机本身的抗干扰能力;快速响应制动功率,使之与负载匹配,可有效改善外界干扰程度;氦透平膨胀机出口压力快速调节,可降低氦透平膨胀机进出口参数,降低影响.%At the end of the experiment of the superconducting Tokamak the oils could produce lots of heat,because of the AC loss,this can induce the pressure of the coil channels raise up for the liquid helium vaporized.The isentropic fficiency and running stability of the helium turbine are severity effected,which directly supplys the liuqid helium to the coils of the superconducting Tokamak.The reasons of the periodicity impact on helium turbines were analysed,the improvement of gas bearing of helium turbine,the improvement of the braking of the helium turbine and the feed back control thought was used to increase the staility of the turbine and decrease the influence of the periodicty impact.The high efficiency gas bearing and the optimized structure of rotors can improve the anti-jamming ability of the helium turbine itself.The braking power being rapidly responded,matched with the load of the turbine can efficiently reduce the external disturbance.Moreover,the fast adjustment for the outlet pressure of the helium turbine can also decrease its inlet and outlet parameters and the impacts.

  13. 基于行为依赖特征的恶意代码相似性比较方法%Dependency-Based Malware Similarity Comparison Method

    Institute of Scientific and Technical Information of China (English)

    杨轶; 苏璞睿; 应凌云; 冯登国

    2011-01-01

    Malware similarity comparison is one of the basic works in malware analysis and detection. Presently, most similarity comparison methods treat malware as CFG, or behavior sequences. Malware writers use obfuscation, packers and other means of technique to confuse traditional similarity comparison methods. This paper proposes a new approach in identifyling the similarities between malware samples, which rely on control dependence and data dependence. First, the dynamic taint analysis is performed to obtain control dependence relations and data dependence relations. Next, a control dependence graph and data dependence graph are constructed. Similarity information is obtained by comparing these two types of graph. In order to take full advantage of the inherent behavior of malicious codes and to increase the accuracy of comparison and anti-jamming capability, the loops are recued and the rubbish is removed by means of the dependence graph pre-processing, which reduces the complexity of the similarity comparison algorithm and improves the performance of the algorithm. The proposed prototype system has been applied to wild malware collections. The results show that the accuracy of the method and comparison capabilities all have an obvious advantage.%恶意代码相似性比较是恶意代码分析和检测的基础性工作之一,现有方法主要是基于代码结构或行为序列进行比较.但恶意代码编写者常采用代码混淆、程序加壳等手段对恶意代码进行处理,导致传统的相似性比较方法失效.提出了一种基于行为之间控制依赖关系和数据依赖关系的恶意代码相似性比较方法,该方法利用动态污点传播分析识别恶意行为之间的依赖关系,然后,以此为基础构造控制依赖图和数据依赖图,根据两种依赖关系进行恶意代码的相似性比较.该方法充分利用了恶意代码行为之间内在的关联性,提高了比较的准确性,具有较强的抗干扰能力;

  14. Research on Lateral Shearing Interferometer for Field Monitoring of Natural Gas Pipeline Leak%新式横向剪切干涉系统对天然气管道泄漏野外监测的研究

    Institute of Scientific and Technical Information of China (English)

    张学锋; 高玉斌

    2012-01-01

    Aimed at the mechanical scanning spectroscopy equipment with poor anti-interference and anti-jamming ability, which affects the accuracy of its natural gas pipeline leak detection in the wild, a new type of lateral shearing interferometer system was designed The system uses a beam splitter to get optical path difference by a mechanical scanning part, and it cancel the introduction of external vibration interference through the linkage between the two beam splitterw. The interference intensity of interference fringes produced was calculated, and analysis of a rotating beam splitter corresponds to the angle of the optical path difference function, solving for the maximum angle of the forward rotation and reverse rotation, which is the maximum optical path range. Experiments using the gas tank deflated simulated natural gas pipeline leak process, in the interference conditions, and the test data of the type WQF530 spectrometer and the new type of lateral shearing interferometer system were comparedt The experimental results show that the relative error of both systems is about 1 % in indoor conditions without interference. However, in interference environment, the error of WQF530 type spectrometer becomes larger, more than 10%, but the error of the new type of lateral shearing interferometer system is still below 5%. The detection accuracy of the type WQF530 spectrometer decreased significantly due to the environment. Therefore, the seismic design of the system can effectively offset power deviation and half-width increases of center wavelength caused by external interference, and compared to conventional mechanical scanning interferometer devices the new system is more suitable for field detection.%针对机械扫描式光谱分析设备抗震、抗干扰能力差等问题影响其在野外检测天然气管道泄露的精确度,设计了一种新式的抗震型横向剪切干涉系统.将分束镜作为机械扫描部分产生光程差,通过两个分束镜之间

  15. Algorithm Design of Trust Aware Recommender Based on Network Dynamic Interference Monitoring%网络动态干扰监控的信任感知推荐算法设计

    Institute of Scientific and Technical Information of China (English)

    张远红; 苗放

    2014-01-01

    网络用户信任感知推荐的准确性设计是提高用户间的社交网络辅助信息信任度的重要依据。传统的网络用户信任感知推荐算法采用的是基于社交网络服务和用户评分的推荐系统,主观性较大,协同过滤效果不好。提出一种基于网络动态干扰监控的信任感知推荐算法设计新方法,设计自适应神经模糊系统网络动态干扰监测算法,构建基于向量空间模型的信任度评价指标体系结构,通过调整网络拓扑权重向量设置信任度周期响应加权变量自适应函数,有效降低迭代算法的运算成本,避免了自适应神经模糊系统网络动态干扰监测加权权重成固化状态,提高抗干扰性能。实验结果表明,算法能使社交网络感知推荐模型的预测误差减少,推荐可靠性优于传统方法。%The accuracy design of network user trust aware recommender is key to improve social network auxiliary informa-tion between the user trust degree. The network user perceived trust traditional recommendation algorithm is used in the recommendation system, social network services and user ratings based on subjectivity, collaborative filtering effect is not good. A new method of algorithm design of recommendation trust is propsoed based on aware network dynamic interference monitoring and adaptive neural fuzzy dynamic interference, the design of monitoring system network construction algorithm, vector space model of trust evaluation index system based on trust, set the periodic response variable weighted adaptive function to adjust the network topology by weight, reduce the iterative algorithm cost, it avoids the adaptive neural fuzzy net-work dynamic interference monitoring weight into curing condition, the anti jamming capability is improved. The experi-mental results show that it can reduce the prediction error, and make social network aware recommendation model is superi-or to the traditional method, the

  16. Simulation of improved active jam method against laser imaging guidance%改进的激光成像制导有源干扰仿真研究

    Institute of Scientific and Technical Information of China (English)

    王昊鹏; 刘泽乾

    2012-01-01

    At present, the laser imaging guidance as a new type of precision way, on the battlefield is playing the more and more major role. Its good detection performance, strong anti-jamming ability, and can work day and night, etc, make its development space more and more wide, threat on military targets are getting more and more serious. However, in view of the laser imaging guidance of interference methods is not ideal but the results, the specific performance: way passive, low success, interference effect is not obvious and so on. Therefore, it is necessary to improve the existing interference measures of laser imaging guidance of interference ability. For laser imaging guidance system of the input signal is active laser interference technology is put forward new way of interference in recent years. In this paper the research foundation, on the optical simulation, especially laser optical simulation for a more in-depth research, and puts forward an improved active laser jamming methods: use the intercept enemy laser detection signal related information, copy the laser signals as interference signals, laser imaging guidance system on enemy for interference, cover important military targets, with lower cost and advantages of active way, so as to improve the laser imaging guidance to the input signal interference ability.%目前,激光成像制导作为一种新型的精确制导方式,在战场上发挥着越来越大的作用。然而,针对激光成像制导的干扰方法效果却并不理想,具体表现为:方式被动、成功率低、干扰效果不明显等。针对激光成像制导系统输入信号的激光有源干扰技术是近几年提出的新型干扰方式。在其研究基础上,对光学仿真,特别是激光光学仿真进行了较为深入的研究,并提出了一种改进的激光有源干扰方式:利用截获的敌方激光探测信号相关信息,复制其激光信号作为干扰信号,对敌方激光成像制导系统进

  17. 痕量N2O气体检测系统的设计与实现%Design and implementation of trace N2O detection system

    Institute of Scientific and Technical Information of China (English)

    郑守国; 李淼; 张健; 张浩东; 胡泽林

    2012-01-01

    A measurement system based on the spectral absorption was established to measure the N2O concentration accurately. First, the relationship of the second-harmonic, the first-harmonic with N2O gas concentration was demonstrated in theory. Then, a N2O detection system for trace concentration was designed based on a Distribute Feedback Laser(DFB). By using the light modulation and lock-in amplifier technologies, weak gas concentration signals in the strong clutter background were analyzed. Finally, the detection performance, anti-jamming capability and the repeatability of test results were verified through experiments. Test results indicate that the system can offer the measuring range from 0 to 1 % , detection limit of 5. 0×10-5 ,and the relative detection error of 0. 11 %. Furthermore, the linear equation is Y=192. 699 09X-0. 006 24, the linearity is 0. 998 07,and the relative standard deviation is 0. 137%. It also proves that the CO2, O2, water vapor, et al. Have no effect on the experimental results. By changing the centre wavelength of the laser,the system can be used in the detection of other greenhouse gases, such as CO2 and CH4.%建立了基于光谱吸收技术的检测系统,用于快速、准确地测量N2O气体浓度.首先,从理论上证明了二次谐波、一次谐波与N2O气体浓度之间的关系;然后,设计了痕量N2O气体浓度检测系统,利用光源调制、锁相放大等技术,实现了强杂波背景下气体浓度弱信号的解析;最后,实验测试了系统的检测性能、抗干扰能力及检测结果的可重复性.测试结果表明,系统能够在0~1%有效检测N2O气体浓度,检测下限为5.0×10-5,相对检测误差为0.11%,检测结果线性方程为Y=192.699 09X-0.00624,线性度为0.99807.多次检测实验表明,系统相对标准偏差为0.137%,CO2、O2、水蒸气等常见气体对检测结果无影响.改变激光器的中心波长,该方法亦可用于CO2,CH4等其它温室气体的检测.

  18. Realization of high-speed real-time optical fiber image transmission system%高速实时光纤图像传输系统的实现

    Institute of Scientific and Technical Information of China (English)

    孙科林; 周维超; 吴钦章

    2011-01-01

    To improve the performance of image transmission systems on optical electronic theodolites, the Rocket 10 IP core based on a Field Programming Gate Array(FPGA) is designed to accomplish the interfaces conversion between parallel camera link and serial optical module. It uses a custom image transmission protocol to build a platform to interconnects the image transmission system with various subsystems. Using this optical fiber transmission channel,the system realizes high-speed real-time image transmmision down to a machine for processing, displaying and recording. It can also compound and transmit commands and synchronization timing up to the camera. This paper describes the system architecture, the software and hardware design for the sender, and receiver, and the key technologies for the system, and introduces attributes of Rocket 10, transceiver state machines for data-packetsand the image transmission protocol. The experimental results indicate that the system will operate at a rate up 2. 5 Gb/s, the transmission link is stable, reliable with no error codes. As the protocol is open-source, users can use the serial data directly. This design breaks through the limitations of traditional optical fiber transmission protocol, and reduces the amount of wiring. The advantages of this system is high bandwidth, high quality images and high anti-jamming level. After a validation test, the system has been applied to various projects.%为提高光电经纬仪上图像传输系统的性能,设计了利用现场可编程门阵列(FPGA)的Rocket IO IP核,完成了Camera link并行接口与光模块串行接口的相互转换.通过自定义的图像传输协议,搭建了图像传输系统与各个分系统的互联平台,实现了高速图像实时传输至机下进行处理、显示和记录,同时在该光纤通道上复合传输相机控制命令和外同步时序.阐述了系统总体结构思想,发送端和接收端的软、硬件设计,介绍了Rocket IO关键属性

  19. Relationships between Soil Loss Tolerance and Karst Rocky Desertification%岩溶区土壤允许流失量与土地石漠化的关系

    Institute of Scientific and Technical Information of China (English)

    白晓永; 王世杰

    2011-01-01

    To understand the relationships between soil loss tolerance ( T value) and karst rocky desertification ( KRD), T value was calculated using digital-distribution map of carbonate rock as- semblages types in this paper, based on pedospheric system theory. And the impacts of T value on KRD were discussed also based on GIS and field survey comprehensively. The results showed that : 1 ) T values in karst areas can be divided into three categories, which are 20,100 and 250 t·km^-2·a^-1 respectively in the purest, purer and nonpure carbonate rock areas but only less than 20 t·km^-2· a-1 in rocky mountain region. 2) In the three carbonate areas where T =20, 100 and 250 t·km^-2· a-1 respectively, KRD incidence rates are 29.86%, 28.12% and 23.25% with KRD severity being 73.55%, 60. 57% and 52. 19%. Therefore, T value in karst areas is very low, and has such characteristics as diversity and heterogeneity in spatial distribu- tion. T value has great impacts on incidence rate and severity of rocky desertified land. In the same social context, or neglecting the differences of human activities, the lower T value is, the smaller the threshold, the weaker anti-jamming capability is, the higher KRD incidence rate is, and the more KRD severity is.%为了解岩溶区土壤允许流失量(T值)与土地石漠化的关系,根据岩溶土壤圈系统论,采用实地调查与GIS空间分析技术,结合贵州碳酸盐岩岩石组合类型测算了T值,并探讨了其对石漠化的影响。结果发现:①岩溶区的T值可分为三大类,在极纯、较纯和不纯的碳酸盐岩地区,T值分别为20、100和250t·km^-2·a^-1,在无土可流、完全是石山的地区,T值只有几吨或更低;②在T=20、100和250t·km^-2·a的地区,石漠化发生率分别为29.86%、28.12%和23.25%,石漠化严重度分别为73.55%、60.57

  20. Measurement Method for Leakage Current of Insulator String Applying LED Optical Fiber Sensor%采用LED光纤传感器的绝缘子串泄漏电流测量方法

    Institute of Scientific and Technical Information of China (English)

    姚陈果; 王建; 冉启华; 李成祥; 米彦

    2012-01-01

    Measuring the leakage current of insulator strings is currently one of the principal means to monitor the contamination level of transmission lines insulator surface;however,due to the complex environment of transmission lines,a large amount of electromagnetic interference will produce much noise at the time of collecting leakage current.Therefore,in order to improve the anti-jamming and accuracy when sensors were used to measure insulator leakage current,an optical fiber sensor was employed to measure leakage current of the insulator strings,in which light emitting diode(LED) was used to detect the current signal as the photoelectric conversion and light signal stability.Taking three-piece XP-160 insulator strings as examples when ρESDD was 0.05~0.2 mg/cm2 and humidity was 85%,we increased the voltage gradually to obtain the leakage current.Results reveal that the optical fiber sensor can achieve selective measurement of leakage current,the positive half cycle or negative half cycle,and the full cycle current can be monitored after differential circuit is improved.Its zero-extinct period is less than 1 ms and response time is limited in 0.1 ms,and its sensitivity reaches 40 V/A.The pertinence coefficients of linear fitting are all higher than 99.94%,and its frequency response is 1~10 kHz,which can meet the basic requirements of the leakage current measurement.%测量绝缘子串的泄漏电流是目前监测输电线路绝缘子串表面污秽状态的主要手段之一,然而由于输电线路环境的复杂性,常常会伴生出大量的电磁干扰,会在泄漏电流的采集源头产生噪声从而导致采集失真。为提高传感器测量绝缘子泄漏电流的抗干扰能力和准确度,采用廉价稳定的光学器件—发光二极管(light emitting diode,LED)设计并制作了1套光纤传感器装置,利用光电转换和光信号的稳定性,以3片XP-160绝缘子串为试验对象,取盐密为0.05~0.2mg/cm2,

  1. cTn Ⅰ detection based on the location surface plasma resonance optical fiber sensors%基于局域表面等离子共振光纤传感器的心肌肌钙蛋白Ⅰ的检测

    Institute of Scientific and Technical Information of China (English)

    刘盛平; 苏森; 陈冠兰

    2013-01-01

    A novel optical fiber sensor based on location surface plasma resonance (LSPR) for cardiac tro-ponin Ⅰ (cTn Ⅰ) detection is proposed. A standard optical fiber is used and its extramural cladding is partially corrupted by hydrofluoric acid. Nanometer silver membranes are formed on the surface of the corrupted fiber. A staphylococcal protein A is used as the ligation mediator between the nanometer silver membranes and cTn Ⅰ monoclonal antibodies. The optical fiber sensor is modified with mouse anti-human cTn Ⅰ monoclonal antibody. It is put into cTn Ⅰ solution with different concentrations. The cTn Ⅰ concentration can be obtained by measuring the extinction peak shift of spectrum curves. The experimental results show that there is a linear relationship between the logarithm of extinction peak shift and the logarithm of mass concentration of cTn Ⅰ in the range of 20-120 ng/mL with a linear dependent coefficient of 0. 996 2. Utilizing the sandwich method,the detection limitation of the optical fiber sensor can achieve 10 ng/mL with a strong ability of anti-jamming to other proteins. The optical fiber sensor based on LSPR proposed here is compact,robust,cost effective,highly sensitive,and suitable for cTn Ⅰ detection.%提出一种应用于心肌肌钙蛋白Ⅰ(cTn Ⅰ)检测的局域表面等离子共振(LSPR)光纤传感器.将标准光纤局部腐蚀掉包层,在其表面形成纳米银膜,用葡萄球菌A蛋白(SPA)作为纳米银膜与cTn Ⅰ单克隆抗体的连接介体,实现鼠抗人cTn Ⅰ单克隆抗体对光纤传感器的修饰,放入不同浓度的cTn Ⅰ溶液中,通过测量传感器光谱曲线的消光峰位移获得溶液中的cTn Ⅰ浓度.实验结果表明,溶液中cTn Ⅰ浓度在20~120 ng/mL范围内,光谱曲线的消光峰位移的对数与cTn Ⅰ质量浓度的对数成线性关系,线性相关系数为0.996 2.利用夹心法,传感器检测限可达10 ng/mL,有较强的抗杂蛋白干扰能力.基于LSPR的光纤传感器件

  2. 基于KVM虚拟桌面的透明消息通道设计%Design of Transparent Message Channel Based on KVM Virtual Desktop

    Institute of Scientific and Technical Information of China (English)

    崔竞松; 何松; 郭迟; 贺汇林

    2014-01-01

    Cloud management platform and end-users of virtual machine generally use proxy software or plug-ins to communicate with each other,but the convenience and anti-jamming capabilities of this method is poor. Aiming at this problem ,this paper proposes a design scheme for transparent message channel between the node provided by cloud service ( the physical host that virtual machine lies in) and the end-user of virtual machine based on virtual desktop on Kernel-based Virtual Machine( KVM) . It builds message control terminal in cloud management platform to receive and process messages that service node sends to end-users of virtual machine, and transforms the messages into images, reads the content of images into specified file in the form of bitmap pixel data as the source of message sending module. It adds message sending module and feedback receiving module into source codes by modifying the source code of Virtual Network Computing ( VNC ) server-side integrated by Qemu-KVM of KVM virtualization platform, integrates the messages into desktop image of the virtual machine,and processes the feedback from the remote terminal of VCN client. Then it builds a two-way interactive message channel between the cloud platform and the end-users which is transparent for virtual machine itself. Experimental result verifies that this scheme is feasible.%云管理平台和虚拟机终端用户间的通信一般采用代理软件或插件,便捷性和抗干扰能力较低。针对该问题,利用基于内核的虚拟机( KVM)虚拟桌面,提出一种云服务提供节点(虚拟机所在物理主机)和虚拟机终端用户之间双向交互的透明消息通道设计方案。在云管理平台中建立消息控制端,用于接收和处理服务节点发往虚拟机终端用户的消息,并将消息转换为图像,使图像内容以位图像素数据格式的方式读出到特定文件中,作为消息发送模块的消息来源。通过修改KVM虚

  3. 导弹非零给定点LQR自动驾驶仪设计%Missile Autopilot Design Based on Non-zero Set Point LQR Method

    Institute of Scientific and Technical Information of China (English)

    雷虎民; 张大元; 肖增博; 薛冬营

    2013-01-01

    静不稳定控制技术是提高空空导弹机动性能的有效手段.针对静不稳定导弹的控制问题,基于非零给定点线性二次型调节器(LQR)理论设计了纵向两回路自动驾驶仪.首先给出一种基于英美弹体坐标系的静不稳定导弹状态空间模型,引入加速度计到质心的距离参量;然后使用非零给定点输出调节器理论,推导了针对一般状态空间表达式描述的系统的最优控制问题,求得了通用解和自动驾驶仪的结构和参数表达式;最后根据经典控制理论对权重系数的选择进行理论研究和仿真分析,并对所设计自动驾驶仪的鲁棒性能以及引入加速度计到质心的距离变量对控制效果的影响进行仿真分析.结果表明所设计的自动驾驶仪有较强的鲁棒性,对静不稳定导弹起到了较好的控制作用.%It's an efficient way to introduce static unstablity in the design of air-to-air missile. A two-loop longitudinal autopilot is designed to solve the problem of control on the statically unstable missile based on the theory of Non-zero set point regulator. Firstly, a missile' s longitudinal model in the style of state space notation is introduced, which is established on the hesperian body axis system, at the same time, the distance between accelerometer and centroid is drawn into the model. And then, the optimal control is derivated from the theory of LQR and Non-zero set point regulator, with which a common result is obtained, and then, the autopilot is designed. At last, the weights are researched with the classical control theory, and the autopilot' s performance is analyzed from its robustness, anti-jamming ability and the affection of the distance between accelerometer and centroid. Results show that the autopilot has a stronger robustness, which can control the statically unstable missile efficiently.

  4. Spherical Reluctance Driving Joint with Magnetic Levitation Modeling and Inverse System Decoupling Control%磁悬浮球形磁阻主动关节的建模与逆系统解耦控制

    Institute of Scientific and Technical Information of China (English)

    曾励; 王军; 徐媛媛

    2011-01-01

    active joint system dynamics model and inverse model. The inverse system model is as a decoupling controller, decoupling the prototype system and get pseudo-linear system. The systems controlled by the pseudo-linear state feedback closed-loop, and its simulation study. Simulation results show that the system has good dynamic response and robust anti-jamming features.

  5. THREE-DIMENSIONAL GLOBAL POSITIONING FOR UNDERGROUND PERSONNEL BASED ON MIMU/Wi-Fi%基于MIMU/WI-FI的井下人员三维全局定位

    Institute of Scientific and Technical Information of China (English)

    罗宇锋; 刘勇; 王红旗; 李芳; 刘志凤

    2015-01-01

    In order to further improve the positioning accuracy of coal mine personnel positioning system and overcome its current disadvantages of only for regional positioning and weak anti-jamming capability,we propose a novel MIMU/Wi-Fi combination-based three-dimensional global positioning system for underground personnel in coal mine.On the basis of analysing the positioning principle of MIMU and Wi-Fi their own,we present the system solution graph which is based on MIMU/Wi-Fi integrated positioning.By analysing the error source of MIMU and Wi-Fi respectively,we build the error model of combination system,and then further use the indirect application of Kalman filtering as well as exert the location combination means to obtain the positioning information of combination system.Finally,we simulate the error model of combination positioning.Simulation results show that the combination positioning method based on MIMU/Wi-Fi has the advantages of high positioning accuracy,strong real-time property,high reliability,and being capable of three-dimensional global positioning. It provides a better way for improving the management level of coal mine safety production,so has higher value in engineering application.%为进一步提高煤矿井下人员定位系统的定位精度,克服目前只能区域定位,抗干扰能力差等缺点,提出一种新型的基于MIMU/WI-FI组合的煤矿井下人员三维全局定位方法。在对MIMU和WI-FI各自定位原理分析的基础上,给出基于MIMU/WI-FI组合定位的系统解算图。通过对MIMU和WI-FI各自的误差源分析,建立组合系统误差模型,进而采用间接法卡尔曼滤波并运用位置组合方式获得组合系统的定位信息。最后,对组合定位误差模型进行仿真。仿真结果表明,基于MIMU/WI-FI的组合定位方法具有定位精度高,实时性强,可靠性好,能够进行三维全局定位等优点,为提高煤矿安全生产管理水平提供了一种更

  6. 高速动车组速度传感器的电磁干扰测试与分析%Electromagnetic interference measurement and analysis of high-speed electric multiple units speed sensor

    Institute of Scientific and Technical Information of China (English)

    严加斌; 朱峰; 李军; 沙淼; 袁德强

    2015-01-01

    Combining with field measurement, the electromagnetic interference issues of CRH380BL speed sensor is studied.Firstly we analyze Hall switch sensor has good anti-jamming capability itself, and point out that car body overvoltage produced by the arc discharge during the bow down will interfere with it .Then the electric dipole theory is used to analyze the characteristics of the electromagnetic field excited during the bow down .From the point that the tangential component of magnetic field is not continuous in the surface of the medium , the reason of car body over-voltage generate is analyzed.From the perspective of the sensor transmission cable shield grounding method , the coupling mechanism of car body over-voltage interference with sensor is also analyzed.The results show that the maximum value of magnetic field is 54.07 dBμA/m and its frequency is mainly distributed around 5 MHz, the over-voltage of No.2 car body is more than 600V.Car body harassment voltage will couple to core wire by the para-sitic capacitance between cable shield and core wire , then coursing interference to speed signal transmitted in the core wire.Through adding protective grounding on No.1 car, the electromagnetic interference of speed sensor from arc discharge effectively is reduced .%结合现场实测,对CRH380BL型动车组速度传感器的电磁干扰问题进行了研究。首先分析了开关型霍尔传感器自身具有良好的抗干扰能力,指出当降弓时产生的电弧放电在车体上产生过电压时将会对其产生干扰。然后采用电偶极子理论分析了降弓时激发的电磁场的特性,从磁场在介质表面切向分量不连续的角度分析了车体过电压产生的原因,最后从传感器传输电缆屏蔽层接地方式的角度分析了车体过电压对传感器的干扰耦合机理。结果表明:降弓时产生的磁场强度最大值为54.07 dBμA/m,且频率主要分布在5 MHz附近,2号车厢车体过电压达600

  7. 3D numerical simulation of the flow field with push-pull hoods containing barriers between them%罩间存在障碍物的吹吸罩流场三维数值模拟

    Institute of Scientific and Technical Information of China (English)

    胡鸿; 易灿南; 廖可兵

    2013-01-01

    为了使吹吸罩达到对污染物的最佳控制,以某企业电镀生产线上行车行进过程中由于镀件表面黏附高浓度槽液而造成室内环境污染为实物模型,建立吹吸罩口间存在障碍物的三维数学模型,利用Fluent计算动力学软件对不同吹风口风速和吸风口风速下的排风罩流场进行数值模拟,经比较确定最佳联合速度,并将模拟结果与经典吹吸速度分布图及试验条件下所测得的污染气体质量分数进行对比分析.结果表明,所建立数学模型是合理的,所确定的最佳效果时的相关参数与经典理论基本一致,可用于工程实际.%This paper attempts to proposo a 3D numerical simulation model of the flow field with push-pull hoods containing barriers between them in hoping to solve the problem of the dispersion of contaminants.As is known,the dispersion of contaminants in different sections of an apparatus can be controlled effectively via a pull-push hood powered by a jet flow.Actually,such device has already been widely used in places where contaminants are serious but can not be eliminated.The said push-pullhoods are usually armed with the following features:minute air volume,perfect pollution control,powerful anti-jam behavior,free from the impact of the process operations.Although no barriers were considered in the former design between the push hood and pull hood in the regular production process according to the processing demands,we still feel it necessary to stress the demand for them,for it is necessary to choose the best velocity of push hood and pull hood to control the containments.Based on the above starting point,we have chosen the computational fluid dynamics (CFD) model to solve the problem.First of all,we have taken the contaminants accumulated in the painted work-pieces with very harmful content adhered in them as a physical model,while assuming that geometrical models are set by the GAMBIT code.Along with it,let the appropriate