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Modified sequential importance resampling filter

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Journal of Systems Engineering and Electronics 2015年第3期26卷 441-449页

作者： Yong Wu Jun Wang Xiaoyong L Yunhe Cao national lab of radar signal processing Xidian University

In order to deal with the particle degeneracy and impov- erishment problems existed in particle filters, a modified sequential importance resampling （MSIR） filter is proposed. In this filter, the resampling is translated into an evolutional process just like the biological evolution. A particle generator is constructed, which introduces the current measurement information （CMI） into the resampled particles. In the evolution, new particles are first pro- duced through the particle generator, each of which is essentially an unbiased estimation of the current true state. Then, new and old particles are recombined for the sake of raising the diversity among the particles. Finally, those particles who have low quality are eliminated. Through the evolution, all the particles retained are regarded as the optimal ones, and these particles are utilized to update the current state. By using the proposed resampling approach, not only the CMI is incorporated into each resampled particle, but also the particle degeneracy and the loss of diver- sity among the particles are mitigated, resulting in the improved estimation accuracy. Simulation results show the superiorities of the proposed filter over the standard sequential importance re- sampling （SIR） filter, auxiliary particle filter and unscented Kalman particle filter.

关键词： sequential importance resampling (SIR) evolution,current measurement information (CMI) unbiased estimation.

Multidimensional Waveform Design for MIMO SAR Interferometry

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Chinese Journal of Electronics 2018年第1期27卷 198-205页

作者： LIU Nan ZHANG Linrang national key laboratory of radar signal processing Xidian University

One key of Multiple-input multiple-output(MIMO) Synthetic aperture radar(SAR) interferometry is the effective separation of the echoes originating from different transmissions. A multidimensional waveform design method for MIMO SAR interferometry is presented. By exploiting the wavenumber shift and Doppler-band shift phenomenon in the design of transmitted signals, the echo separation can be efficiently accomplished via the filtering operations in range-frequency domain and azimuth-spatial domain. Such waveform design can meet the requirement of MIMO SAR imaging on integrated cross interference level without reduce the swath width. Such waveform design also improves the coherence between the independent observations and enlarges the unambiguity range of height estimation. The results of the numerical simulations demonstrate the feasibility of the proposed waveform design method.

关键词： Synthetic aperture radar(SAR) interferometry Multiple-input multiple-output(MIMO) Multidimensional waveform design Echo separation

An eigenstructure-based 2D DOA estimation method using dual-size spatial invariance array

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Science China(Information Sciences) 2011年第1期54卷 163-171页

作者： YANG XueYa,CHEN BaiXiao & CHEN YunHai national key lab of radar signal processing,Xidian University,Xi’an 710071,China national key lab of radar signal processing Xidian University Xi’an China

A sparse planar array vertically placed in y-z plane is proposed to improve the angle estimation accuracy of sources in low angle region with reflection *** two sizes of spatial invariances along both dimensions,the array estimates the azimuth and elevation angles using unitary ESPRIT(estimation of signal parameters via rotational invariance techniques).The first spatial invariance with a displacement of half-wavelength yields unambiguous coarse estimates of high-variance,while the second spatial invariance with much larger a displacement of subarrays obtains cyclically ambiguous fine estimates of *** final estimates are obtained by disambiguating fine estimates with coarse estimates.A novel pairing scheme is proposed to pair both the azimuth and elevation,coarse and fine angle estimates of the same *** addition, a new method is presented to calculate 2D angles,which substitutes the estimated elevation angle into the sin relative to the y-axis to get the azimuth *** real-valued processing and array aperture extension, the new DOA measuring method de-correlates the multipath signals and enhances angle resolution with no extra antennas and computational *** results show the effectiveness of the proposed technique and its advantages over the conventional methods.

关键词： DOA estimation sparse array correlated signals unitary ESPRIT dual-size spatial invariances

Linear feature detection based on ridgelet

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Science China(Technological Sciences) 2003年第2期46卷 141-152页

作者：侯彪刘芳焦李成 key lab for radar signal processing Xidian University

Linear feature detection is very important in image processing. The detection efficiency will directly affect the performance of pattern recognition and pattern classification. Based on the idea of ridgelet, this paper presents a new discrete localized ridgelet transform and a new method for detecting linear feature in anisotropic images. Experimental results prove the efficiency of the proposed method.

关键词： linear feature detection, ridgelet transform, wavelet transform, Radon transform.

Direction synthesis in DOA estimation for monostatic multiple input multiple output (MIMO) radar based on synthetic impulse and aperture radar (SIAR) and its performance analysis

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Science China(Technological Sciences) 2008年第6期51卷 656-673页

作者： ZHAO GuangHui CHEN BaiXiao ZHU ShouPing national key lab for radar signal processing Xidian UniversityXi’an 710071China

A new direction synthetic method for monostatic multiple input multiple output (MIMO) radar is presented based on synthetic impulse and aperture radar (SIAR) system. Concerned with the monostatic MIMO radar which simultaneously emits orthogonal signals with multi-carrier-frequency and possesses sparsely distributed transmitting and receiving arrays with respective location, as well as the situation for the presence of multipath propagation in the low flying target’s echo, the method integrates the aperture of the transmitting arrays with the receiving arrays to form the digital beam-forming (DBF) in azimuth and elevation dimensions. And a study has been made of planar general MUSIC algorithm based on decorrelating the multipath signals of multi-carrier-frequency MIMO radar. Through compensat-ing the phase delay of both the transmitting and the receiving arrays and synthe-sizing the transmitting beam in two dimensions at the receiver, the angular resolu-tion and measurement accuracy are improved and the computational complexity is reduced after transforming the three-dimensional (3D) parameter estimation prob-lem into a two-dimensional (2D) one. Finally, the Cramer-Rao Bounds (CRBs) of DOA estimation for azimuth and elevation is put forward with the exsiting multipath propagation. Results of computer simulation demonstrate the validity of the new method.

关键词： SIAR monostatic MIMO radar multipath propagation super resolution general MUSIC algorithm Cramer-Rao Bounds

High-resolution algorithm based on temporal-spatial extrapolation

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Journal of Systems Engineering and Electronics 2010年第1期21卷 9-15页

作者： Xueya Yang Baixiao Chen Feilin Qi national key lab for radar signal processing Xidian University Xi' an 710071 E R. China

To enhance the resolution of parameter estimation with limited samples received by a short passive array, an iterative nonparametric algorithm for estimating the frequencies and direction-of-arrivals （DOAs） of signals is proposed. The cost function is constructed using 12-norm Gaussian entropy combined with an additional constraint, 12-norm constraint or linear constraint. By minimizing the cost functions in the temporal and the spatial dimensions using corresponding iteration algorithms respectively, the sparse discrete Fourier transforms （DFTs） of temporal and spatial samples are obtained to represent the extrapolated sequences with much larger sizes than the original samples. Then frequency and angle estimates are obtained by performing the traditional simple methods on the extrapolated sequences. It is shown that the proposed algorithm offers increased resolution and significantly reduced sidelobes compared with the periodogram and beamforming based methods. And it achieves high precision compared with the high-resolution method with lower computational burden. Some numerical simulations and real data processing results are presented to verify the effectiveness of the method.

关键词： temporal-spatial extrapolation frequency estimation direction-of-arrival discrete Fourier transform.

Clutter suppression for hypersonic vehicle-borne radar with frequency diverse array

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Journal of Systems Engineering and Electronics 2017年第3期28卷 481-492页

作者： Xuzi Wu Zheng Liu Rong Xie national key laboratory of radar signal processing Xidian UniversityXi’an 710071China

The seriously range-ambiguous clutter is one of the main problems in clutter suppression for hypersonic vehicle-borne forward-looking radar. An approach based on the frequency diverse array (FDA) technique is proposed to mitigate the range ambiguous clutter. The frequency increment is designed to distinguish the clutter at ambiguous ranges and suppress the clutter by using a subspace projection algorithm. On the platform with high altitude or limited array antennas, the proposed method performs better for its independence of the elevation degrees-of-freedom (DOF). Finally, simulation results verify the effectiveness of the proposed method.

关键词： hypersonic vehicle forward-looking array radar clutter suppression frequency diverse array

IMM Robust Cardinality Balance Multi-Bernoulli Filter for Multiple Maneuvering Target Tracking with Interval Measurement

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Chinese Journal of Electronics 2021年第6期30卷 1141-1151页

作者： YANG Biao ZHU Shengqi HE Xiongpeng national laboratory of radar signal processing Xidian University

This paper presents a novel Interacting multi-model(IMM) Robust Cardinality balance multitarget multi-Bernoulli(R-CBMe MBer) filter to solve the maneuvering target tracking problem in the case of interval measurement, unknown detection probability and unknown clutter density. In essence, IMM R-CBMe MBer filter is an extended application of R-CBMe MBer *** the IMM R-CBMe MBer filter, the target state is first extended to distinguish clutter from the real *** detection probability and model probability of the target can be adaptively updated. Then, generalized likelihood function and IMM algorithm are introduced to interactively predict and update the state of the target in the IMM R-CBMe MBer filtering process. In addition,a particle application of the IMM R-CBMe MBer filter is given, and a numerical experiment is designed under nonlinear conditions. Meanwhile, Doppler information of the target is employed to estimate the velocity of each maneuvering target. Numerical experiments also verify that the IMM R-CBMe MBer filter can effectively estimate the target position, target velocity, target detection probability and clutter number in the condition of unknown detection probability, unknown clutter rate and interval measurement.

关键词： probability image filtering maneuvering target tracking problem clutter unknown detection probability target state model probability imm robust cardinality balance multiBernoulli filter novel Interacting multimodel robust cardinality balance multitarget multiBernoulli IMM R-CBMeMBer filter target detection probability interval measurement target tracking multiple maneuvering target tracking object detection IMM R-CBMeMBer filtering process tracking filters

Property analysis of bistatic forward-looking SAR with arbitrary geometry

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Journal of Systems Engineering and Electronics 2016年第1期27卷 111-127页

作者： Ziqiang Meng Yachao Li Mengdao Xing Zheng Bao national laboratory of radar signal processing Xidian University

Bistatic forward-looking synthetic aperture radar（SAR） has many advantages and applications owing to its twodimensional imaging *** could be various imaging configurations because of the geometric flexibility of bistatic platforms,resulting in kinds of models built independently among which there could be some similar even the same motion *** research on such systems in a more comprehensive and general point of view is required to address their difference and *** analysis of bistatic forwardlooking SAR with arbitrary geometry is achieved including stripmap and spotlight modes on airborne platform,missile-borne platform,and hybrid platform of *** is placed on azimuth space variance of some key parameters significantly affecting the subsequent imaging processing,based on which the frequency spectra are further described and compared considering respective features of different platforms for frequency imaging algorithm *** results confirm the effectiveness and correctness of our analysis.

关键词： bistatic forward-looking synthetic aperture radar(SAR) comprehensive research property analysis azimuth space variance.