[1]红外动目标识别跟踪系统的dsp+fpga实现




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Tracking of The Moving Target


277. Real-time detection of rapid moving infrared target on variation background

Chen, Yong (School of Automation Engineering, University of Electronic Science and Technology of China); Liu, Xia; Huang, Qi Source: Infrared Physics and Technology, v 51, n 3, January, 2008, p 146-151

ISSN: 1350-4495 CODEN: IPTEEY

Publisher: Elsevier


Abstract: For the condition where monitor point and target move rapidly simultaneously, a real-time target detection algorithm is proposed in this paper. The algorithm is based on a region theory which fuses four region algorithms, i.e., region of interest (ROI) algorithm, region enhancement algorithm, region growing algorithm and sequence image interframe region algorithm. It obtains ROI by analyzing infrared target and locally enhances ROI on the basis of histogram statistic to extract target region. Then it segments the target by region growing algorithm. Finally, it determines the target by the characteristics of sequence image interframe and pattern matching. Experiment results in vehicle infrared navigation system show that the algorithm based on the region theory is very efficient and real-time to detect rapid moving target on variation background. © 2007 Elsevier B.V. All rights reserved. (11 refs.)

278. First results of ground moving target analysis in TerraSAR-X data

Suchandt, Steffen (Remote Sensing Technology Institute, German Aerospace Center (DLR)); Runge, Hartmut; Eineder, Michael; Breit, Helko; Kotenkov, Alexander; Balss, Ulrich Source: International Geoscience and Remote Sensing Symposium (IGARSS), 2007 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2007, 2008, p 3943

CODEN: IGRSE3 ISBN-10: 1424412129

Conference: 2007 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2007, Jun 23-28 2007, Barcelona, Spain

Publisher: Institute of Electrical and Electronics Engineers Inc.


Abstract: The advanced high-resolution German SAR satellite TerraSAR-X is scheduled to be launched at the end of May 2007. Due to its daylight and weather independent applicability in combination with a large spatial coverage and a short acquisition time, SAR has become a promising tool for traffic monitoring in recent years. Ground Moving Target Indication (GMTI) techniques shall be applied to TerraSAR-X data in order to demonstrate the capability of a space borne SAR sensor to monitor traffic flows on highways. A series of GMTI experiments will be carried out during the commissioning phase of the TerraSAR-X satellite. In first trials, cars, which are equipped with special radar reflectors and GPS receivers, will be used as moving target references that are imaged in TerraSAR-X data takes. In a follow on experiment, arbitrary cars on motorways will be imaged simultaneously by TerraSAR-X and by an airborne high-resolution camera. Car tracks extracted from the series of the optical images shall serve as a reference for the evaluation of the TerraSAR-X moving target data in this case. The paper presents first results of the data evaluation. An experimental GMTI processing system is used to detect and measure moving targets in both single-channel and dual-channel data. The dual-channel data, which enable the application of well established GMTI methods like the Along-Track Interferometry (ATI) or Displaced Phase Centre Array (DPCA) techniques, are acquired either in the so-called "aperture switching" mode with virtual multiple receiving channels or in the Dual-Receive Antenna (DRA) mode with physically separated receiving channels. The paper reports on the analysis of the first experimental GMTI data by using different detection and measurement strategies. This includes the adapted processing of the SAR raw data with respect to the moving target signals, the incorporation of GIS data in the detection and measurement process and the application of different detectors for across- and along-track velocity components of the moving cars. The quality of the data is thoroughly analyzed and conclusions are drawn for the development and the performance of a fully automatic GMTI processing system for TerraSAR-X. Furthermore, an outlook on the planned experiments is given. © 2007 IEEE.
279. A new method for moving target indication and detection in multi-channel SAR data

Lidicky, Ludvik (IRCTR, Delft University of Technology) Source: International Geoscience and Remote Sensing Symposium (IGARSS), 2007 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2007, 2008, p 4802-4805

CODEN: IGRSE3 ISBN-10: 1424412129

Conference: 2007 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2007, Jun 23-28 2007, Barcelona, Spain

Publisher: Institute of Electrical and Electronics Engineers Inc.
Abstract: A new and fast algorithm for MTI/MTD processing is presented. This algorithm is based on a formation of SAR images from each channel and using these for separation between moving and stationary targets. First, the problem is described by means of a generalized model. Then, an inverse problem is formulated and some of its approximate solutions by means of the Fourier transform are given. The approximate solutions are used to show how one can resolve stationary targets and moving ones completely regardless their distribution in space or reflectivity. The only criterion used is the velocity of a target. Further, it is shown how moving targets and stationary targets can be separated from processed, that is focused, SAR images. © 2007 IEEE. (9 refs.)
280. Development of a baseband signal ATI-SAR simulator for ground moving target indication

Zhou, Zheng-Shu (University of Adelaide); Bates, Bevan D.; Dong, Yunhan Source: International Geoscience and Remote Sensing Symposium (IGARSS), 2007 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2007, 2008, p 4505-4508

CODEN: IGRSE3 ISBN-10: 1424412129

Conference: 2007 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2007, Jun 23-28 2007, Barcelona, Spain

Publisher: Institute of Electrical and Electronics Engineers Inc.
Abstract: Along-track SAR interferometry has long been used to measure ocean surface currents with small velocities. There is a significant potential to employ this technique to detect slow ground moving targets with small radar cross-sections. In this paper, we present the development of a baseband signal simulator on ground moving target indication with along-track SAR interferometry. We summarize current state-of-the-art along-track SAR interferometry techniques and algorithm developments for ground moving target detection, and consider the case of an airborne SAR operated in the stripmap mode. And then we propose to investigate and develop advanced techniques for potential civilian and military applications in Australia. © 2007 IEEE. (11 refs.)
281. Adaptive spatial-temporal-spectral filters for point target detection

Hu, Jing (State Key Laboratory for Image Processing and Intelligent Control, Huazhong University of Science and Technology); Zhang, Tian-Xu; Lin, Liang-Kui Source: Jisuanji Xuebao/Chinese Journal of Computers, v 31, n 1, January, 2008, p 161-169 Language: Chinese

ISSN: 0254-4164 CODEN: JIXUDT

Publisher: Science Press


Abstract: In allusion to the problem of dim moving spot target detection in the presence of highly structured background clutter, the authors put forward a new algorithm of adaptive spatial-temporal-spectral multidimensional filter (called ASTS filter) according to the applicable principle of the Wiener-Hopf equations, and present a new algorithm to implement multidimensional information fusion. In this way, there are three processes. Firstly, the quality of inosculate of spatial-temporal-spectral multidimensional information is studied. Secondly, the filter template which in allusion to the moving dim spot target is constructed. Lastly, the Recursive Least Squares (RLS) filter is applied to the multi-spectral infrared images with highly structured background clutter. In general, the gray of pixels will be used as the input parameter of the RLS filter, and the large-size matrix will bring the huge computational load. The spatial-temporal-spectral multidimensional information is used as the input parameter in the new filter, and then it can shun the large-size matrix and reduce the computational load. By the way, the new filter can get the higher output SNR (Signal Noise Ratio). A great deal of experimental data testifies the well performance of this algorithm in filtering. (12 refs.)
282. Modified method of SAR moving target detection and imaging based on fractional Fourier transform

Deng, Bin (School of Electronic Science and Engineering, National University of Defense Technology); Qin, Yu-Liang; Wang, Hong-Qiang; Li, Xiang Source: Dianzi Yu Xinxi Xuebao/Journal of Electronics and Information Technology, v 30, n 2, February, 2008, p 326-330 Language: Chinese

ISSN: 1009-5896 CODEN: DKXUEC

Publisher: Science Press


Abstract: To overcome the shortcomings of the conventional method of SAR moving target detection and imaging based on the Fractional Fourier Transform (FrFT), a modified method, which combines filtering in fractional Fourier domain, reassigned spectrogram and CLEAN, is presented for the detection, parameter estimation and imaging of moving targets. This method is able to estimate precisely the initial Doppler frequency and the Doppler centroid, and to distinguish between multiple targets lying in the same line in the time-frequency plane. The transform formulas between FrFT numeral results and Doppler parameters are also given in the paper. Simulated results prove the validity of the approach. (8 refs.)
283. Dynamic space reconfiguration for Bayesian search and tracking with moving targets

Lavis, Benjamin (School of Mechanical and Manufacturing Engineering, University of New South Wales); Furukawa, Tomonari; Durrant Whyte, Hugh F. Source: Autonomous Robots, v 24, n 4, May, 2008, p 387-399

ISSN: 0929-5593 CODEN: AUROF2

Publisher: Kluwer Academic Publishers


Abstract: This paper presents a technique for dynamically reconfiguring search spaces in order to enable Bayesian autonomous search and tracking missions with moving targets. In particular, marine search and rescue scenarios are considered, highlighting the need for space reconfiguration in situations where moving targets are involved. The proposed technique improves the search space configuration by maintaining the validity of the recursive Bayesian estimation. The advantage of the technique is that autonomous search and tracking can be performed indefinitely, without loss of information. Numerical results first show the effectiveness of the technique with a single search vehicle and a single moving target. The efficacy of the approach for coordinated autonomous search and tracking is shown through simulation, incorporating multiple search vehicles and multiple targets. The examples also highlight the added benefit to human mission planners resulting from the technique's simplification of the search space allocation task. © 2008 Springer Science+Business Media, LLC. (29 refs.)
Ei controlled terms: Bayesian networks - Computer simulation - Motion estimation - Numerical methods - Target tracking
284. Vision based data fusion for autonomous vehicles target tracking using interacting multiple dynamic models

Jia, Zhen (United Technologies Research Center); Balasuriya, Arjuna; Challa, Subhash Source: Computer Vision and Image Understanding, v 109, n 1, January, 2008, p 1-21

ISSN: 1077-3142 CODEN: CVIUF4

Publisher: Academic Press Inc.


Abstract: In this paper, a novel algorithm is proposed for the vision-based object tracking by autonomous vehicles. To estimate the velocity of the tracked object, the algorithm fuses the information captured by the vehicle's on-board sensors such as the cameras and inertial motion sensors. Optical flow vectors, color features, stereo pair disparities are used as optical features while the vehicle's inertial measurements are used to determine the cameras' motion. The algorithm determines the velocity and position of the target in the world coordinate which are then tracked by the vehicle. In order to formulate this tracking algorithm, it is necessary to use a proper model which describes the dynamic information of the tracked object. However due to the complex nature of the moving object, it is necessary to have robust and adaptive dynamic models. Here, several simple and basic linear dynamic models are selected and combined to approximate the unpredictable, complex or highly nonlinear dynamic properties of the moving target. With these basic linear dynamic models, a detailed description of the three-dimensional (3D) target tracking scheme using the Interacting Multiple Models (IMM) along with an Extended Kalman Filter is presented. The final state of the target is estimated as a weighted combination of the outputs from each different dynamic model. Performance of the proposed fusion based IMM tracking algorithm is demonstrated through extensive experimental results. © 2006 Elsevier Inc. All rights reserved. (33 refs.)
285. Imaging of a moving target with rotating parts based on the hough transform

Zhang, Qun (Department of Electrical and Computer Engineering, National University of Singapore); Yeo, Tat Soon; Tan, Hwee Siang; Luo, Ying Source: IEEE Transactions on Geoscience and Remote Sensing, v 46, n 1, January, 2008, p 291-299

ISSN: 0196-2892 CODEN: IGRSD2

Publisher: Institute of Electrical and Electronics Engineers Inc.


Abstract: The rotation of structures in a target introduces additional frequency modulations on the returned signals and also generates sidebands about the center Doppler frequency of the target. In other words, the body image will be contaminated due to the interference from the rotating parts. In this paper, an imaging method for moving targets with rotating parts is presented. The method is simple to implement and is based on the Hough transform (HT), which is widely used in image processing. Using the standard HT and an extended HT, we put forward a separation method by detecting the straight lines and the sinusoids on the spectrogram, respectively. A computer simulation is given to illustrate the effectiveness of the proposed method. © 2007 IEEE. (31 refs.)
286. IR target tracking based on mean shift and particle filter

Wei, Kun (College of Automation, Northwestern Polytechnic University); Zhao, Yong-Qiang; Pan, Quan; Zhang, Hong-Cai Source: Guangdianzi Jiguang/Journal of Optoelectronics Laser, v 19, n 2, February, 2008, p 213-217 Language: Chinese

ISSN: 1005-0086 CODEN: GUJIE9

Publisher: Board of Optronics Lasers


Abstract: A novel method for infrared target tracking which combines mean shift and particle filter was proposed in order to improve the tracking accuracy and robustness. Based on the particle filter, the mean shift was introduced as an iterative mode seeking procedure, in which particles move toward the maximal posterior kernel density estimation of target state. The weights of particle samples are updated as the mean shift iterative operating. The posterior distribution of the infrared target is approximated by a set of re-weighted samples, while the infrared target tracking is implemented by the particle filter algorithm which constructed by the sample set. Experimental results show that the proposed method is more effective and robust than the independent standard particle filter and mean shift. (16 refs.)
287. Space-based moving target positioning using radar with a switched aperture antenna

Ender, Joachim H. G. (FGAN-FHR); Gierull, Christoph H.; Cerutti-Maori, Delphine Source: International Geoscience and Remote Sensing Symposium (IGARSS), 2007 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2007, 2008, p 101-106

CODEN: IGRSE3 ISBN-10: 1424412129

Conference: 2007 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2007, Jun 23-28 2007, Barcelona, Spain

Publisher: Institute of Electrical and Electronics Engineers Inc.
Abstract: Ground moving target indication (GMTI) by space based radar can effectively only be performed with a multiaperture / multi-channel system or a satellite cluster [I]. To keep weight, power consumption, data rate and costs low, the technique of switching subapertures from pulse to pulse has been proposed. While the detection performance using STAP (space-time adaptive processing) has been analysed in several publications, the estimation performance and the mechanisms leading to good or bad aperture switching strategies, have not yet been treated sufficiently. In fact, aperture partitions well suited for detection must not necessarily be good for estimation. This paper is thought as a contribution to fill the knowledge gaps concerning repositioning algorithms and performance analysis. © 2007 IEEE. (15 refs.)
288. Simulation of flight target echo for bistatic/multistatic HF ground wave radar

Wei, Yin-Sheng (Dept. of Electronics, Harbin Inst. of Technology); Liu, Yuan; Ji, Zhen-Yuan Source: Xi Tong Gong Cheng Yu Dian Zi Ji Shu/Systems Engineering and Electronics, v 30, n 1, January, 2008, p 53-56 Language: Chinese

ISSN: 1001-506X CODEN: XGYDEM

Publisher: Chinese Institute of Electronics


Abstract: The simulation of bistatic/multistatic HF ground wave radar echo is analyzed. According to the characteristic of variable distance sum between moving target and radar for bistatic/multistatic HF ground wave radar, a new method is proposed and analyzed to simulate target echo in this radar, which is based on iterative method. The result indicates that the new method can simulate the target echo accurately, and provide exact data for further signal processing. (9 refs.)
Ei controlled terms: Radar target recognition - Antenna grounds - Iterative methods - Signal processing - Tracking radar
289. A novel distributed sensor positioning system using the dual of target tracking

Zhang, Liqiang (Department of Computer and Information Sciences, Indiana University South Bend); Cheng, Qiang; Wang, Yingge; Zeadally, Sherali Source: IEEE Transactions on Computers, v 57, n 2, February, 2008, p 246-250

ISSN: 0018-9340 CODEN: ITCOB4

Publisher: Institute of Electrical and Electronics Engineers Computer Society


Abstract: As one of the fundamental issues in wireless sensor networks (WSNs), the sensor localization problem has recently received extensive attention. In this work, we investigate this problem from a novel perspective by treating it as a functional dual of target tracking. In traditional tracking problems, static location-aware sensors track and predict the position and/or velocity of a moving target. As a dual, we utilize a moving location assistant (LA) (with a global positioning system (GPS) or a predefined moving path) to help location-unaware sensors to accurately discover their positions. We call our proposed system Landscape. In Landscape, an LA (an aircraft, for example) periodically broadcasts its current location (we call it a beacon) while it moves around or through a sensor field. Each sensor collects the location beacons, measures the distance between itself and the LA based on the received signal strength (RSS), and individually calculates their locations via an Unscented Kalman Filter (UKF)-based algorithm. Landscape has several features that are favorable to WSNs, such as high scalability, no intersensor communication overhead, moderate computation cost, robustness to range errors and network connectivity, etc. Extensive simulations demonstrate that Landscape is an efficient sensor positioning scheme for outdoor sensor networks. © 2008 IEEE. (59 refs.)
290. Design of the high-powered clutter suppression system based on ADSP-TS203

Zheng, Yingxi (Research Institute of Electronic Science and Technology, University of Electronic Science and Technology of China); Zong, Zhulin Source: ICCCAS 2007 - International Conference on Communications, Circuits and Systems 2007, ICCCAS 2007 - International Conference on Communications, Circuits and Systems 2007, 2008, p 816-818

Conference: ICCCAS 2007 - International Conference on Communications, Circuits and Systems 2007, Jul 11-13 2007, Kokura, Japan

Publisher: Institute of Electrical and Electronics Engineers Computer Society


Abstract: The paper studies the design to implement moving target indication (MTI) and moving target detection (MTD) based on a piece of ADSP-TS203. Digital Signal Processor (DSP) provides great flexibility for the design of the software. After pulse compression, the radar echoes including clutter, noise and targets are transmitted to DSP for MTI and MTD. The system mainly adopts the arithmetic of three-pulse elimination to realize MTI. MTD can be completed by using a Narrow-Band-Doppler-Filter group in frequency domain. At last, it's verified that this system can restrain clutter and distinguish the targets effectively, which has been tested on the hardware. Meanwhile, the improvement factor is also improved. The system can be widely used in radar signal processing. (6 refs.)
291. New multi-channel SAR-GMTI frequency STAP algorithm

Wei, Jun (School of Electronics and Information Engineering, Beijing Univ. of Aeronautics and Astronautics); Sun, Jin-Ping; Yuan, Yun-Neng; Liu, Shu-Jun; Mao, Shi-Yi Source: Xi Tong Gong Cheng Yu Dian Zi Ji Shu/Systems Engineering and Electronics, v 30, n 1, January, 2008, p 1-5 Language: Chinese

ISSN: 1001-506X CODEN: XGYDEM

Publisher: Chinese Institute of Electronics


Abstract: Based on Ender's work, the theoretical formula of the clutter suppression in frequency STAP is deduced in-depth and the mathematical expression of the output signal is also obtained, and then a new SAR-GMTI algorithm by multi-channel SAR is proposed. At first, the clutter is suppressed based on STAR, then the moving targets are matched based on dechirp method, lastly the moving targets are detected and their moving parameters are estimated. The analyses in theory and simulation results show that the new algorithm is effective. (11 refs.)
292. RKP based secure tracking in wireless sensor networks

Jiahao, Wang (Coll. of Computer Science and Engineering, Univ. of Electronic Science and Technology); Zhiguang, Qin; Ji, Geng; Shengkun, Wang Source: Journal of Systems Engineering and Electronics, v 19, n 1, February, 2008, p 175-183

ISSN: 1004-4132 CODEN: JSEEFQ

Publisher: Editorial Dept. of Systems Engineering and Electronics


Abstract: To enhancing the wireless sensor network's security in target tracking and locating application, this article proposes a tracking cluster based mobile cluster distributed group rekeying protocol (MCDGR). Based on the given sensitivity, sensors can locate the moving object in the monitored area and form a tracking cluster around it. This tracking cluster can follow the target logically, process data on the target and report to the sink node, and thus achieve the tracking function. We introduce a multi-path reinforcement scheme, q-composition scheme and one-way cryptographic hash function based random key predistribution algorithm (RKP), which can guarantee a high accuracy and security and a low energy consumption on the same time in large-scale sensor networks. © 2008 The Second Academy of China Aerospace Science and Industry Cooperation. (14 refs.)

293. Multiple targets vector miss distance measurement accuracy based on 2-D assignment algorithms

Bingyi, Fang (Dept. of Electronic Engineering, Beijing Inst. of Technology); Siliang, Wu Source: Journal of Systems Engineering and Electronics, v 19, n 1, February, 2008, p 76-80

ISSN: 1004-4132 CODEN: JSEEFQ

Publisher: Editorial Dept. of Systems Engineering and Electronics
Abstract: An extension of 2-D assignment approach is proposed for measurement-to-target association for improving multiple targets vector miss distance measurement accuracy. When the multiple targets move so closely, the measurements can not be fully resolved due to finite resolution. The proposed method adopts an auction algorithm to compute the feasible measurement-to-target assignment with unresolved measurements for solving this 2-D assignment problem. Computer simulation results demonstrate the effectiveness and feasibility of this method. © 2008 The Second Academy of China Aerospace Science and Industry Cooperation. (9 refs.)
294. Micro-visual servoing for micro-assembly

Chen, Guoliang (School of Mechantronic Engineering, Wuhan University of Technology); Huang, Xinhan; Wang, Min Source: Jixie Gongcheng Xuebao/Chinese Journal of Mechanical Engineering, v 44, n 2, February, 2008, p 82-86 Language: Chinese

ISSN: 0577-6686 CODEN: CHHKA2

Publisher: Editorial Office of Chinese Journal of Mechanical Engineering


Abstract: The pose adjustment of manipulator led and controlled by micro-vision is deduced for the problem how to make three points on its end-effector move for three set points in three-dimensional space respectively. A move planning is designed to avoid the collision and intervention of parts and to hold the end-effector in the visual field of the microscope, which stipulates one point moving along a line to its goal position and the other two points moving to their respective goal positions by rotating on the first point. According to this planning, a method based on the distance and angle between lines is proposed to estimate the image feature deviation, and the image Jacobian and kinematic model of manipulator based on the image feature are defined and built. An optimal control algorithm for the system with image delay is derived by the minimization of a cost function that allows weights to be placed on the error of the image features and the control signal. A micro-visual servoing control structure is designed to improve the positional accuracy, which includes a proportional controller and an optimal controller. The switch between the two controllers is selected by an error switch. Using a six-degree micromanipulator, experiments for adjusting line pose and tracking a moving target are performed to validate these researches. The results demonstrate that these researches are feasible and correct, and the location error is less than 2 pixels, which can satisfy the needs of the micro assembly. (9 refs.)
295. Multitarget detection and estimation based on passive multilateral TDOAs of transient signals

Carevic, Dragana (Maritime Operations Division, Defence Science and Technology Organisation, HMAS Stirling) Source: IEEE Transactions on Signal Processing, v 56, n 1, January, 2008, p 418-424

ISSN: 1053-587X CODEN: ITPRED

Publisher: Institute of Electrical and Electronics Engineers Inc.


Abstract: Recently, a Modified Deterministic Annealing Expectation Maximization (MDAEM) algorithm has been proposed [D. Carevic, "Automatic estimation of multiple target positions and velocities using passive TDOA measurements of transients," IEEE Transactions on Signal Processing, vol. 55, no. 2, pp. 424-436, 2007] for the estimation of the motion parameters of multiple targets moving in cluttered three-dimensional (3-D) underwater environments. In many situations, the number of targets in the measurements batch is not known, and the MDAEM algorithm is run for an inexact (guessed) number of the motion models, where, usually, the guessed number of models is larger than the true number of targets. This correspondence describes a detection procedure that determines which of the motion models estimated by the algorithm are related to the true targets in the measurements batch. © 2007 IEEE. (14 refs.)
296. Optimal measurement strategies for target tracking by a biomimetic underwater vehicle

Guo, Jenhwa (Department of Engineering Science and Ocean Engineering, National Taiwan University) Source: Ocean Engineering, v 35, n 5-6, April, 2008, p 473-483

ISSN: 0029-8018

Publisher: Elsevier Ltd


Abstract: This study presents a novel navigation and control system allowing a biomimetic-autonomous underwater vehicle (BAUV) to track a target. A Bayesian approach using an extended Kalman filter and combined localization and environmental mapping by a BAUV are implemented. This strategy selects the best sensor measurement by choosing one of several forward-looking directions. The body of the BAUV moves in a cyclical pattern; thus, an inexpensive echo sounder can be installed on the BAUV head to detect environmental features without the need for expensive scanning devices. The localization and environmental mapping problem is then transformed into a non-linear two-point boundary value problem. Optimal policies are to maintain the accuracy of predicted states and to approach minimal observation cost by solving the control problem. A line-of-sight guidance law is utilized that drives the BAUV to the target. An approach that controls the motion of the body/caudal fin and pectoral fins of the BAUV is utilized for target tracking. Estimation, measurement, and control processes are integrated to form a working system. Experiments using a test bed BAUV confirm the effectiveness of the proposed approach. © 2008 Elsevier Ltd. All rights reserved. (16 refs.)
297. Improving coherence of complex image pairs obtained by along-track bistatic SARs using range - Azimuth prefiltering

Wang, Tong (National Laboratory of Radar Signal Processing, Xidian University); Bao, Zheng; Zhang, Zhen-Hua; Ding, Jin-Shan Source: IEEE Transactions on Geoscience and Remote Sensing, v 46, n 1, January, 2008, p 3-13

ISSN: 0196-2892 CODEN: IGRSD2

Publisher: Institute of Electrical and Electronics Engineers Inc.


Abstract: An along-track interferometric synthetic aperture radar (SAR) can be used for ground moving target indication (GMTI) by comparing two SAR images obtained at different observation times. Different geometries of the two observations bring the decorrelation noise, which will degrade the detection performance. For bistatic SARs, the decorrelation theory is quite different from that for monostatic ones. This paper deals with the coherence between two complex SAR images formed by two along-track bistatic SARs with different baseline lengths. Using the single scattering model, the coherence between the two echoes collected by the two receivers is investigated, and the full-coherence conditions are derived. Then, a new method based on range - azimuth prefiltering is proposed to improve the coherence of complex image pairs. As the precise prefiltering is complicated, its three approximate implementations are given. The effects of prefiltering on SAR images are also analyzed. Finally, simulation results validate the effectiveness of the proposed method. © 2007 IEEE. (18 refs.)
298. Analysis and approximation of performance bound for two-observer bearings-only tracking

Xu, Ben-Lian (Department of Information and Control Engineering, Changshu Institute of Technology); Chen, Qing-Lan; Wu, Zheng-Yi; Wang, Zhi-Quan Source: Information Sciences, v 178, n 8, Apr 15, 2008, p 2059-2078

ISSN: 0020-0255 CODEN: ISIJBC

Publisher: Elsevier Inc.


Abstract: This paper presents the analytic recursive formulas of Cramer-Rao lower bound (CRLB) for the switching models system, in which the target moves either with a constant velocity or with a constant speed and a constant turn rate. For the case of two-observer bearings-only maneuvering target tracking, a reliable maneuver detection method is investigated and then utilized to approximate the theoretic CRLB. Finally, to demonstrate the agreement between the approximated CRLB using the proposed maneuver detection method and the theoretic one, a large number of Monte-Carlo runs under different maneuvering scenarios are conducted. Correctness of the analytic recursive formulas of CRLB and effectiveness of the proposed maneuver detection method are verified from these simulations. © 2007 Elsevier Inc. All rights reserved. (21 refs.)
299. An optimal and robust attitude-tracking control of spacecraft based on inverse system method

Yuan, Chang-Qing (School of Aerospace, Tsinghua University); Li, Jun-Feng; Wang, Tian-Shu; Baoyin, He-Xi Source: Gongcheng Lixue/Engineering Mechanics, v 25, n 2, February, 2008, p 214-218 Language: Chinese

ISSN: 1000-4750 CODEN: GOLIEB

Publisher: Tsinghua University


Abstract: This paper deals with the attitude tracking control of spacecraft. For many space missions, spacecrafts are required to point their payload, such as high-gain antenna and high-gain camera, at a fixed target on the Earth or a moving target on orbit. A new method is presented to calculate the reference attitude angle, angular velocity and acceleration. An analytical expression is given. The attitude dynamics is strong-coupled and non-linear during large angle maneuver, thus it is difficult to apply the traditional robust control design methods. On this account, error quaternion is introduced to describe the dynamics, which avoids the problem of singularity. Besides, in order to utilize the design of the robust controller, a desired approximate pseudo-linear system is obtained by inverse system method in the presence of model error and disturbances. Furthermore, based on the transition theorem between the robust control and the optimal control, the robust control problem is transformed into an optimal control problem. This approach can also be applied to more complex object such as multi-body spacecraft, and the simulation results are presented to demonstrate the effectiveness of the proposed design method. (10 refs.)
300. Wide area traffic monitoring with the PAMIR system

Cerutti-Maori, D. (Forschungsgesellschaft fur Angewandte Naturwissenschaften e.V. (FGAN)); Klare, J.; Burger, W.; Brenner, A.R.; Ender, J.H.G. Source: International Geoscience and Remote Sensing Symposium (IGARSS), 2007 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2007, 2008, p 3567-3570

CODEN: IGRSE3 ISBN-10: 1424412129

Conference: 2007 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2007, Jun 23-28 2007, Barcelona, Spain

Publisher: Institute of Electrical and Electronics Engineers Inc.
Abstract: This paper presents some Scan-MTI results, which were obtained with the SAR-GMTI system PAMIR developed at FGAN-FHR. The Scan-MTI mode was designed to rapidly monitor wide areas for ground moving targets. The scan operation enables detection of targets from different aspect angles with a high revisit rate. This mode is particularly adapted to perform an efficient traffic monitoring, as well. © 2007 IEEE. (9 refs.)
301. Adaptive update interval tracking based on adaptive grid interacting multiple model

Cheng, T. (Department of Electronic Engineering, University of Electronic Science and Technology of China); He, Z.; Tang, T. Source: IET Radar, Sonar and Navigation, v 2, n 2, , 2008, p 104-110

ISSN: 1751-8784

Publisher: Institution of Engineering and Technology


Abstract: The update interval is adjustable in the phased array radar system. An adaptive update interval algorithm based on the adaptive grid interacting multiple model is proposed. The moving step size of mid-model's parameter is utilised to adapt the update interval to the target's behaviour. Furthermore, a controllable parameter is introduced to balance the tracking precision and the system load. The effectiveness of the algorithm is verified through simulation. The simulation results also demonstrate that the proposed algorithm can save much system resource while achieving the same tracking quality as the fixed update interval algorithm. © The Institution of Engineering and Technology 2008. (17 refs.)
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