Showing papers on "Moving target indication published in 2007"

Approach for single channel SAR ground moving target imaging and motion parameter estimation

Abstract: In recent years, ground moving target imaging in synthetic aperture radar (SAR) has attracted the attention of many researchers all over the world. A novel approach is proposed for the ground moving target imaging and motion parameter estimation using single channel SAR. First, a second-order generalised keystone formatting method is used to compensate for the range curvature. Secondly, the estimated slope of the target echo's envelope is used for the range walk compensation. Thirdly, Doppler parameters of moving targets obtained via spectral analysis are used for the imaging and positioning of ground moving targets. Finally, motion parameters of moving targets can be estimated on the basis of the relationship between Doppler and motion parameters. Both numerical and experimental results are provided to demonstrate the performance of the proposed approach.

RapidIO for radar processing in advanced space systems

Abstract: Space-based radar is a suite of applications that presents many unique system design challenges. In this paper, we investigate use of RapidIO, a new high-performance embedded systems interconnect, in addressing issues associated with the high network bandwidth requirements of real-time ground moving target indicator (GMTI), and synthetic aperture Radar (SAR) applications in satellite systems. Using validated simulation, we study several critical issues related to the RapidIO network and algorithms under study. The results show that RapidIO is a promising platform for space-based radar using emerging technology, providing network bandwidth to enable parallel computation previously unattainable in an embedded satellite system.

A New Application for PolSAR Imagery in the Field of Moving Target Indication/Ship Detection

Abstract: Recent analysis of a polarimetric synthetic aperture radar (PolSAR) velocity experiment has shown that azimuth ambiguities can provide useful information for the detection of moving targets with an across-track velocity component in PolSAR images using cross-polarization clutter cancellation. This paper examines this phenomenon using theoretical analysis and simulations and illustrates its application with experimental results. It is shown that, for reciprocal scatterers, the phase difference between HV and VH images is zero, whereas for HV and VH ambiguities, the phase difference is pi. For land applications, clutter cancellation is essential for the detection of moving targets in PolSAR images. For maritime applications, it can be used to distinguish images from ambiguities. However, it is important to note that the underlying physical reasons for the performance of clutter cancellation are entirely different from ground moving target indication along-track interferometric SAR. It is also shown that cross-pol clutter cancellation is related to filtering of a double-rate-sampled single-channel SAR signal.

Capabilities of Dual-Frequency Millimeter Wave SAR With Monopulse Processing for Ground Moving Target Indication

Abstract: Ground moving target indication (GMTI) for synthetic aperture radar (SAR) provides information on nonstatic objects in radar imagery of a static ground scene. An efficient approach for GMTI is the use of multichannel SAR systems for a space- and time-variant analysis of moving targets. This allows the indication, correction of position displacement, and estimation of radial velocity components of moving targets in a SAR image. All three steps are possible due to a determinable Doppler frequency shift in the radar signal caused by radial target movement. This paper focuses on the millimeter wave (mmW) SAR system MEMPHIS with multichannel amplitude-comparison monopulse data acquisition and the ability to use carrier frequencies of 35 and 94 GHz simultaneously, making it a dual-frequency SAR. This paper includes mmW-specific SAR GMTI considerations, an adaptive algorithm to collect velocity and position information on moving targets with mmW monopulse radar, and a discussion on GMTI blind speed elimination and target velocity ambiguity resolving by dual-frequency SAR. To determine the capabilities of both, system and algorithm, three large-scale experiments with MEMPHIS in different environments are presented

Method and apparatus for simultaneous synthetic aperture radar and moving target indication

Abstract: Method and apparatus for simultaneous synthetic aperture radar and moving target detection. A plurality of independent radio frequency signals are generated and applied to separate radiating/receiving antenna elements. Signals are generated as basis functions, such that moving target detection and synthetic aperture radar signals are constructed from individual waveform components in space, time, frequency, and coding. Waveform components are sorted and combined at reception. Received data is simultaneously processed to extract synthetic aperture radar images and moving target indication detections.

Investigation of MIMO SAR for interferometry

Abstract: In conventional interferometric synthetic aperture radar (SAR), the coherent combination of two SAR images reconstructed from two separated receive antennas is used for digital elevation model (DEM) or moving target indication (MTI), depending on the antenna constellations. In this paper we propose the novel system concept for interferometric SAR (InSAR) based on Multiple-Input Multiple-Output (MIMO) configuration. A digital beam forming (DBF) SAR system based on multiple receive antennas is extended to MIMO SAR concepts. We investigate its performance and processing features, particularly, associated with the received signal quality and the transmitter diversity. Using orthogonal linear frequency modulated (LFM) signal, it is shown that space-time coding scheme can be applied to SAR system in multiple-input single-output (MISO) configuration. A simple Alamouti scheme enhances the signal-to-noise ratio (SNR) and extracts a spatial diversity. Combining this transmitter spatial diversity and digital beam forming on receive, we introduce the potential of high resolution wide swath (HRWS) observation for Interferometry.

The Strength Pareto Evolutionary Algorithm 2 (SPEA2) applied to simultaneous multi- mission waveform design

Abstract: This paper furthers the development of the application of evolutionary computation, specifically genetic algorithms (GAs) to the design of simultaneously transmitted orthogonal waveforms. The goal of the application is to determine a suite of "optimal" waveforms (in the Pareto sense) for a single platform radar system performing multiple radar missions simultaneously. The waveform suite is determined by applying the strength Pareto evolutionary algorithm 2 (SPEA2) developed by Zitzler, Laumanns & Theile (2002) to find waveform parameters that successfully realize a set of objectives particular to a variety of radar missions. The objectives to optimize are dictated by the particular missions of interest. The mapping of these objective functions to actual radar performance parameters is used in the SPEA2 algorithm to determine how best to simultaneously perform multiple radar missions such as GMTI, AMTI, SAR etc. using a single radar system in a Pareto optimal sense. Preliminary results are presented for a scaled down multi-mission multi-objective function scenario.

Moving target detection for synthetic aperture radar via shadow detection

Abstract: In this paper a novel technique is presented for detecting moving targets in SAR imagery by tracking the shadow of the target over multiple looks instead of using the target direct energy return Unlike the SAR image of a moving target that is blurred and displaced, the shadow of the target is displayed at the true target location The detection performance using shadow is primarily independent of the target radar cross-section and depends upon the clutter to noise signal level A change detection method is developed that provides detection via identification of the target shadow as an outlier from a background distribution The background is inferred from a sequence of SAR images It is shown that simple temporal averaging by alignment of the image for estimating the background works reasonably well with SAR images offering good shadow contrast The technique was successfully demonstrated initially using real radar data from a short range spotlight SAR system Results against weaker shadow signals at longer stand-off range have also proved very encouraging showing a moving target being detected at 10 km standoff range (5 pages)

Adaptive moving target indicator (MTI) clutter rejection filter for radar systems

Abstract: Apparatus for providing moving target indicator (MTI) filtering in the presence of clutter for a radar receiver employing digital pulse compression to provide at an output a compressed digital pulse for application to the input of a MTI digital filter, including a digital adaptive filter of the same weight as the MTI filter and operative to receive the compressed pulse to provide at outputs of the filter a set of weighted filter coefficients, wherein the weighted coefficients are applied to the MTI filter during a predetermined clutter mode.

Optimum relative speed discretisation for detection of moving objects in wide band SAR

Abstract: Here, Ground moving target indication (GMTI) using synthetic aperture radar (SAR) is considered. SAR GMTI requires that relative speed between the target and the SAR platform is included in the detection algorithm. A separation between the true relative speed and the relative speed used in the SAR process will cause unfocused targets, and decrease detectability. Blind hypotheses of relative speeds are used in the detection phase of moving targets in SAR. The step size between the hypotheses (or discretisation step) in relative speed involves a trade off between the number of hypotheses to test and detectability. A large number of tests will increase detectability but will also increase computation load and vice versa. The relevance of relative speed increases as the azimuth integration time gets larger. Long integration time is associated with low signature moving target detection in strong clutter environments, or for SAR GMTI at low frequencies. The optimum discretisation of normalised relative speed for moving target detection has been determined. The optimum discretisation is derived from the moving target impulse response. Use of optimum discretisation reduces the computation burden in SAR GMTI and secures the detectability.

Enhancing GMTI Performance in Non-Stationary Clutter Using 3D STAP

Abstract: In side-looking ground moving target indication (GMTI) radar, the 2-dimensional (2D) space time (azimuth-Doppler) domain can adequately define a clutter spectrum which is accurate for all range gates. However, in applications where the array boresight is not perpendicular to the velocity vector (e.g. forward-looking radar), the azimuth-Doppler clutter spectrum exhibits a dependence on elevation angle-of-arrival, creating range-varying (but elevation-dependent) clutter statistics, or non-stationary clutter. Classical space time adaptive processing (STAP) algorithms suffer substantial performance losses in non-stationary clutter since classical STAP assumes clutter stationary along the range (training) dimension. Planar arrays are inherently able to observe the azimuth-Doppler clutter spectrum as a function of the elevation angle, a capability which linear arrays lack. The incorporation of the planar array's vertical dimension into the joint azimuth-Doppler (2D) STAP domain has previously resulted in 3D STAP. This paper demonstrates the ability of 3D STAP to solve the non-stationary clutter problem by accounting for the elevation-dependent clutter statistics in a 3D covariance matrix. A forward-looking array is used to provide non-stationary clutter, and the performance of 2D and 3D versions of the adaptive matched filter (AMF) and joint domain localized (JDL) are used in a close-in sensing paradigm. The results show a >55 dB improvement in output SINR near the clutter null using 3D STAP algorithms in lieu of 2D STAP algorithms applied to the same (subarrayed) data.

Reduced-Dimensional Processing for Ground Moving Target Detection in Distributed Space-Based Radar

Abstract: With multisatellite radar systems, several additional features are achieved: multistatic observation, interferometry, ground moving target indication (GMTI). In this letter, a new reduced-dimensional method based on joint pixels sum-difference (Sigma-Delta) data for clutter rejection and GMTI is proposed. The reduced-dimensional joint pixels Sigma-Delta data are obtained by the orthogonal projection of the joint pixels data of different synthetic aperture radar (SAR) images generated by a multisatellite radar system. In the sense of statistic expectation, the joint pixels Sigma-Delta data contain the common and different information among SAR images. Then, the objective of clutter cancellation and GMTI can be achieved by adaptive processing. Simulation results demonstrate the effectiveness and robustness of the proposed method even with clutter fluctuation and image coregistration errors

Space-based moving target positioning using radar with a switched aperture antenna

Abstract: Ground moving target indication (GMTI) by space based radar can effectively only be performed with a multi- aperture / multi-channel system or a satellite cluster [1]. 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.

Multinomial pattern matching for high range resolution radar profiles

Abstract: Airborne ground moving-target indication (GMTI) radar can track moving vehicles at large standoff distances. Unfortunately, trajectories from multiple vehicles can become kinematically ambiguous, resulting in confusion between a target vehicle of interest and other vehicles. We propose the use of high range resolution (HRR) radar profiles and multinomial pattern matching (MPM) for target fingerprinting and track stitching to overcome kinematic ambiguities. Sandia's MPM algorithm is a robust template-based identification algorithm that has been applied successfully to various target recognition problems. MPM utilizes a quantile transformation to map target intensity samples to a small number of grayscale values, or quantiles. The algorithm relies on a statistical characterization of the multinomial distribution of the sample-by-sample intensity values for target profiles. The quantile transformation and statistical characterization procedures are extremely well suited to a robust representation of targets for HRR profiles: they are invariant to sensor calibration, robust to target signature variations, and lend themselves to efficient matching algorithms. In typical HRR tracking applications, target fingerprints must be initiated on the fly from a limited number of HRR profiles. Data may accumulate indefinitely as vehicles are tracked, and their templates must be continually updated without becoming unbounded in size or complexity. To address this need, an incrementally updated version of MPM has been developed. This implementation of MPM incorporates individual HRR profiles as they become available, and fuses data from multiple aspect angles for a given target to aid in track stitching. This paper provides a description of the incrementally updated version of MPM.

Optimum radar signal for detection in clutter [Correspondence]

Abstract: It is shown that in order to maximize the detectability of a radar target in clutter whose Doppler is unknown and is uniformly distributed over the Doppler bandwidth a simple CW or narrowband signal is optimal The optimality criterion is the average deflection coefficient, with the averaging being over target Doppler frequency Most remarkably the result does not depend on the clutter spectrum but holds for any distribution of clutter energy with frequency

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

Abstract: Summary form only given. 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 were to 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, were to be used as moving target references that are imaged in TerraSAR-X data takes. In a follow on experiment, arbitrary cars on motorways were to 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-channeldata. 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.

A Large Along-Track Baseline Approach for Ground Moving Target Indication Using TanDEM-X

Abstract: In the paper a new method for ground moving target indication (GMTI) using two satellites (i.e. the TerraSAR-X and the TanDEM-X satellite) together is presented. The along-track baseline between the satellites is chosen to be in the order of several kilometres, so that each satellite observes the same moving vehicles at different times in the order of one to several seconds. The proposed method allows the estimation of the ground velocity of the moving targets as well as the estimation of the broadside positions without the need of complex bistatic processing techniques.

A Net Track Solution to Pose-Angular Tracking of Maneuvering Targets in Clutter with HRR Radar

Abstract: Maintaining track continuity is a challenging task for large area persistent surveillance with high target density, rapid target maneuvering, and low target-to-clutter ratio When the sensor revisit interval is long, measurement-to-track association becomes rather difficult Although maneuvering targets can be discriminated via Doppler processing, clutter still masks moving targets at certain aspect angles This creates a blind zone for GMTI (ground moving target indicator) radar, which may extend as large as 25% of the azimuth angles For high-value targets that may undergo evasive maneuvers, a net track solution coordinating multiple looks from a netted set of sensors is set forth in this paper to ensure continuous monitoring Target visibility therefore needs to be factored into netted radar platform coordination and sensor systems management For ground targets, their heading is mostly aligned with the longitudinal axis The target pose thus carries kinematic information about the direction of velocity vector that can be used to assist tracking of maneuvering targets In this paper, the range profiles of high range resolution (HRR) radar are used for pose angular estimation of maneuvering targets in clutter A pose-sensitive classifier provides matching scores that are converted into likelihoods and updated over time in a probabilistic manner Pose angular tracking from individual sensors in the network is fused to cover the blind zone encountered by individual sensors A software simulation environment that produces range profiles based on the RF signatures of moving targets is used in the study Simulation results for pose angular tracking in clutter are presented to illustrate the net track solution concept and its performance

Approach of multiple moving targets detection for microwave surveillance sensors

Abstract: Multiple moving targets detection is one of the fundamental problems in information acquisition. In this paper, the use of a transformable period and symmetrical linear frequency modulated (TPS-LFM) waveform for microwave surveillance sensor multiple moving targets identification, is proposed. In order to accurately estimate target's true position and velocity, a relatively unknown yet powerful technique, the so-called fractional Fourier transform (FrFT), is applied to estimate the moving target parameters. By mapping a target's signal onto a fractional Fourier axis, the FrFT permits a constant-velocity target to be focused in the fractional Fourier domain thereby affording orders of magnitude improvement in signal-clutter-ratio. Moving target velocity and position parameters are derived and expressed in terms of an optimum fractional angle and a measured fractional Fourier position, allowing a target to be accurately located. Moreover, to resolve the problem whereby weak targets are covered by the sidelobes of strong ones, the CLEAN technique is also applied. Simulation results show that the method is effective in estimating target velocity and position parameters for microwave surveillance sensors.

All Source Adaptive Fusion for Aided Navigation in Non-GPS Environment

Abstract: An innovative approach for navigation in non-GPS environment is presented based on all source adaptive fusion of any available information encompassing passive imaging data, digital elevation terrain data, IMU/GPS, altimeters, and star tracker. The approach provides continuous navigation through non-GPS environment and yields an improved navigation in the presence of GPS. The approach also provides reduced target location error and moving target indication.

Motion Parameter Estimation of Doppler-Ambiguous Moving Targets in SAR-GMTI

Abstract: In an along-track interferometric SAR system, the discrete sampling of moving target signals can give rise to two types of ambiguity: Doppler ambiguity, and interferometric angle ambiguity. These ambiguities lead to ambiguities in target velocity estimation. Range cell migration of moving targets is unambiguous in target velocity. Hence, it can be used for resolving the ambiguities in target velocity estimation mentioned above. The wave number domain algorithm as well as the chirp scaling algorithm is adapted to moving target signals. In order to focus moving target signals with arbitrary velocities both approaches are extended to arbitrary Doppler frequency ands. Moving target signals distributed over two neighbouring PRF bands are especially difficult to detect and analyze because the sgnal splits into two parts. It is shown that the two parts appear at different positions in the SAR image and have different ATI phases. They show up as two weaker targets since the energy is split between them. It is demonstrated how the two targets can be identified as possibly the same target, and how they can be properly focussed by adaptation of the SAR focussing algorithms.

UWB FSR for air targets detection: Preliminary analysis

Abstract: This paper is dedicated to the preliminary analysis of the utilisation of an ultra wideband (UWB) signal in forward scattering radar (FSR) for air target detection. Some advantages of the wide spectrum ranging signal use are shown: ground clutter reduction, target resolution, altitude and direct target position evaluation.

Real-time image processing and fusion for a new high-speed dual-band infrared camera

Abstract: A dual-band infrared camera system based on a dual-band quantum well infrared photodetector (QWIP) has been developed for acquiring images from both the mid-wavelength (MWIR) and long-wavelength (LWIR) infrared spectral band. The system delivers exactly pixel-registered simultaneously acquired images. It has the advantage that appropriate signal and image processing permit to exploit differences in the characteristics of those bands. Thus, the camera reveals more information than a single-band camera. It helps distinguishing between targets and decoys and has the ability to defeat many IR countermeasures such as smoke, camouflage and flares. Furthermore, the system permits to identify materials (e.g. glass, asphalt, slate, etc.), to distinguish sun reflections from hot objects and to visualize hot exhaust gases. Furthermore, dedicated software for processing and exploitation in real-time extends the application domain of the camera system. One component corrects the images and allows for overlays with complementary colors such that differences become apparent. Another software component aims at a robust estimation of transformation parameters of consecutive images in the image stream for image registration purposes. This feature stabilizes the images also under rugged conditions and it allows for the automatic stitching of the image stream to construct large mosaic images. Mosaic images facilitate the inspection of large objects and scenarios and create a better overview for human observers. In addition, image based MTI (moving target indication) also for the case of a moving camera is under development. This component aims at surveillance applications and could also be used for camouflage assessment of moving targets.

Real-Time Space-Time Adaptive Processing on the STI CELL Multiprocessor

Abstract: Space-time adaptive processing (STAP) has been widely used in modern radar systems such as ground moving target indication (GMTI) systems in order to suppress jamming and interference. However, its baseband signal processing part usually requires huge amount of computing power. This paper presents the real-time implementation of an STAP baseband signal processing flow on the state-of-the-art STI CELL multiprocessor which enables the concept of software-defined radar (SDR). SIMD vectorization is applied to speed-up the kernel subroutines of STAP such as the QR decomposition, forward/backward substitution and fast Fourier transform (FFT). Benchmarking results of both the kernel subroutines and the overall flow are presented. Furthmore, based on the result of earlier benchmarking, optimized task partitioning and scheduling methods are proposed by us to improve the overall performance so that the overhead is reduced to the minimum.

An Integral Detection Scheme for Moving Object Indication in Dual-Channel High Resolution Spaceborne SAR Data

Abstract: Upcoming SAR satellite missions like TerraSAR-X or RADARSAT-2 will deliver high resolution dual channel SAR data with large coverage. These new missions - together with rising interest in area-wide traffic monitoring - motivate spaceborne GMTI as an attractive alternative to conventional traffic data acquisition. However, a moving object appears distorted in the SAR image since the well-known stationary world assumption in the SAR focusing process is violated. In this paper, a detection approach is presented, which considers simultaneously the effects of azimuthal and radial motion of an object. The mathematical framework of this detector combines information of the measured signal, the expected signal, and their variances. Furthermore, the performance of the proposed algorithm is analysed using experimental airborne SAR data.

Modelling 3D rigid-body object motion and structure estimation with HRR/GMTI measurements

Abstract: When traditional single-point target tracking algorithms are directly applied to multiple-point rigid targets, filter divergence and data association problems occur. By introducing the concepts of global motion, local motion and structure parameters, and employing motion-induced invariants on local motion and structure parameters, we have developed several kinematic and measurement models to simultaneously estimate the motion and structure information of a 3D rigid-body target from high range resolution (HRR) and ground moving target indicator (GMTI) measurements. To test the ability of the proposed modelling methods in handling false alarms, occlusions and HRR measurements without correspondence information, several data association approaches are also proposed, that is permutation, combination-permutation, dummy measurements, and dynamically changing the interested number of scattering centres. Simulation results have shown that the proposed modelling methods can successfully estimate both the motion and structure information of an object by using HRR and GMTI measurements with a proper data association method.

Parameter Estimations of SAR Moving Target Based on DPCA-FrFT Algorithm

Abstract: The DPCA-FrFT algorithm is used in this paper to realize the localization and velocity estimations in both ground range direction and azimuth direction when it comes to a two-aperture radar system. The moving point target's echo model of two-aperture SAR system is established. Then, the linear frequency-modulated characteristics of moving target's DPCA signal is elaborated. According to this characteristics, fractional Fourier transform is adopted to detect the moving target and estimate parameters. Because of the good capability of DPCA technique for clutter cancellation and the nice effect of FrFT for chirp signal detection, the DPCA-FrFT algorithm can suppress the clutter and realize the localization and velocity estimations well in different signal-to-noise ratio conditions. The simulation results validate the effectiveness of this algorithm.

Radar pulse compression for point target and distributed target using neural network

Abstract: An important study of the responses to the point target and the distributed target of the radar echoes processed by a neural network pulse compression (NNPC) algorithm is presented in this paper. For whatever the purpose of a radar system, both of the point target and distributed target echoes are received simultaneously. It is always necessary and helpful to discriminate them clearly while detecting the desired target, which will reduce the influence for each other in pulse compression processing. However, in most of the pulse compression algorithms, it is only considered the radar purpose to process one type of the targets but neglect the other. This will make either the presence of a point target's range sidelobes masking and corrupting the observation of the weak distributed target nearby or a distributed target with extended range interfering with the detection of the neighboring point target. By completely considering the interactions of a point target with a distributed target, we acquire all the possible data occurred in the procedure. Using these valid data, we can train the backpropagation (BP) network to construct it as a well performance of NNPC. To compare with the traditional algorithms such as direct autocorrelation filter (ACF), least squares (LS) inverse filter, and linear programming (LP) filter based on 13-element Barker code (B13 code), the proposed NNPC provides the requirements of high signal-to-sidelobe ratio, low integrated sidelobe level (ISL), and high target discrimination ratio. Simulation results show that this NNPC algorithm has significant advantages in targets discrimination ability, range resolution ability, and noise rejection performance while processing the interaction of point target with distributed target, which are superior to the traditional algorithms.