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A new approach to dual-band polarimetric radar remote sensing image classification

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Science in China(Series F) 2005年第6期48卷 747-760页

作者： XU Junyi YANG Jian peng yingning Department of Electronic Engineering Tsinghua University Beijing 100084 China

It is very important to efficiently represent the target scattering characteristics in applications of polarimetric radar remote sensing. Three probability mass functions are introduced in this paper for target representation： using similarity parameters to describe target average scattering mechanism, using the eigenvalues of a target coherency matrix to describe target scattering randomness, and using radar received power to describe target scattering intensity. The concept of cross-entropy is employed to measure the difference between two scatterers based on the probability mass functions. Three parts of difference between scatterers are measured separately as the difference of average scattering mechanism, the difference of scattering randomness and the difference of scattering intensity, so that the usage of polarimetric data can be highly efficient and flexible. The supervised/unsupervised image classification schemes and their simplified versions are established based on the minimum cross-entropy principle. They are demonstrated to have better classification performance than the maximum likelihood classifier based on the Wishart distribution assumption, both in supervised and in unsupervised classification.

关键词： polarimetric radar remote sensing dual-band image classification cross-entropy

High Performance Viterbi Decoder on Cell/B.E.

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China Communications 2009年第2期6卷 150-156页

作者： Lai Junjie Tang Jun peng yingning Chen Jianwen High Speed Signal Processing Laboratory.Electronic Engineering Department Tsinghua University Beijing China IBM China Research Laboratory

Viterbi decoding is widely used in many radio systems. Because of the large computation complexity, it is usually implemented with ASIC chips, FPGA chips, or optimized hardware accelerators. With the rapid development of the multicore technology, multicore platforms become a reasonable choice for software radio (SR) systems. The Cell Broadband Engine processor is a state-of-art multi-core processor designed by Sony, Toshiba, and IBM. In this paper, we present a 64-state soft input Viterbi decoder for WiMAX SR Baseband system based on the Cell processor. With one Synergistic Processor Element (SPE) of a Cell Processor running at 3.2GHz, our Viterbi decoder can achieve the throughput up to 30Mb/s to decode the tail-biting convolutional code. The performance demonstrates that the proposed Viterbi decoding implementation is very efficient. Moreover, the Viterbi decoder can be easily integrated to the SR system and can provide a highly integrated SR solution. The optimization methodology in this module design can be extended to other modules on Cell platform.

关键词： viterbi decoding WiMAX tail-biting cell multi-core

On detection performance of MIMO radar for Rician target

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Science in China(Series F) 2009年第8期52卷 1456-1465页

作者： TANG Jun WU Yong peng yingning WANG XiuTan Department of Electronic Engineering Tsinghua University Beijing 100084 China

By using spatial diversity, multiple-input-multiple-output （MIMO） radar can improve detection performance for fluctuating targets. In this paper, we propose a spatial fluctuation target model for MIMO radar, where targets are classified as non-fluctuating target, Rayleigh target and Rician target. Based on Stein＇s lemma, we use relative entropy to study detection performance of optimum detector for Rician target. It is found that in low signal noise ratio （SNR） region, the performance improvement of MIMO radar for detecting Rician target depends on array gain, which is related to the number of receivers. In high SNR region, the improvement of performance depends on diversity gain, which is related to the product of the number of receivers and the number of transmitters. The conclusions of this paper are important for designing MIMO radar system.

关键词： MIMO radar relative entropy Rician target detection performance

On detection performance and system configuration of MIMO radar

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Science in China(Series F) 2009年第7期52卷 1250-1257页

作者： TANG Jun WU Yong peng yingning WANG XiuTan Department of Electronic Engineering Tsinghua University Beijing 100084 China

Multiple-input multiple-output （MIMO） radar is a new concept with some new characteristics, such as multiple orthogonal waveforms and omnidirectional coverage. Based on Stein＇s lemma, we use relative entropy as a precise and general measure of error exponent to study detection performance for both MIMO radar and phased array radar. And based on derived analytical results, we further study the system configuration problem of Bistatic MIMO radar systems, where transmitters and receivers are located in different positions. Some interesting results are presented. For phased array radar, when the total numbers of transmitters and receivers are fixed, we should always make the number of transmitters equal to the number of receivers. For MIMO radar, we should use a small number of transmitters in low signal noise ratio （SNR） region, and make the number of transmitters equal to the number of receivers in high SNR region. These results are instructive for deployment of bistatic MIMO radar systems in the future.

关键词： MIMO radar relative entropy system configuration

PRF-ambiguity resolution for SAR by contrast minimization in range-Doppler domain

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Frontiers of Electrical and Electronic Engineering in China 2007年第3期2卷 302-306页

作者： YU Mingcheng XU Jia peng yingning Department of Electronic Engineering Tsinghua UniversityBeijing 100084China

An algorithm was developed to accurately estimate the Doppler centroid,which is needed for high-quality synthetic aperture radar(SAR)image formation by resolving the SAR pulse repetition frequency(PRF)*** algorithm uses the SAR range migration to resolve the PRF-ambiguity by searching for a PRF-ambiguity number that minimizes the intensity contrast in the range-Doppler *** results show that the approach,compared with traditional methods for resolving the SAR PRF ambiguity,is more suitable for both high contrast scenes such as urban areas and low contrast scenes such as ***,the approach is more computationally efficient for there are no time-consuming correlations or fast Fourier transform(FFT)operations needed in the range-Doppler domain and only part of the range cells are used in the calculation.

关键词： SAR PRF-ambiguity resolution range migration range-Doppler domain scene contrast

Sub-aperture based blind speed side lobe （BSSL） suppression in Radon Fourier transform （RFT）

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Sub-aperture based blind speed side lobe （BSSL） suppressio...

MIMO-SAR waveforms separation based on virtual polarization filter

2012 IEEE 11th International Conference on Signal Processing(ICSP 2012)

作者： Lichang Qian Jia Xu Wenfeng Sun yingning peng Airforce Early Warning Academy Dept.Of Electronic Engineering Tsinghua Univ.

ISBN: (纸本)9781467321969

The Radon-Fourier transform （RFT） is a novel long-time coherent integration method we have previously proposed for far-range, weak and high speed target detection. Nevertheless, due to the discrete pulse sampling, finite range resolution and limited integration time, the blind speed side lobe （BSSL） phenomenon may inevitably appear in the RFT output. The existence of BSSL can lead to large false alarms and detection loss in the RFT. To address this problem, a new BSSL suppression method is proposed in this paper. By jointly processing the two different sub-aperture RFT outputs, the BSSL can be easily suppressed without integration loss. Furthermore, two evaluation criterions of the BSSL suppression are also proposed. Finally, detailed numerical experiments are provided to demonstrate the effectiveness of the proposed method.

关键词： Radon-Fourier transform (RFT) blind speed side lobe (BSSL) suppression sub-aperture processing evaluation criterion

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Science China(Information Sciences) 2015年第4期58卷 25-36页

作者： MENG CangZhen XU Jia XIA Xiang-Gen LIU Feng LONG Teng MAO ErKe YANG Jian peng yingning Department of Electronic Engineering Tsinghua University Air force Early Warning Academy School of Information and Electronics Beijing Institute of Technology Department of Electrical and Computer Engineering University of Delaware

The unwanted coupling exists inevitably among multiple orthogonal waveforms in a same frequency area for multiple-input and multiple-output synthetic aperture radar(MIMO-SAR). In this paper, a new polarized MIMO-SAR model is established with two transmitting antennas and multiple receiving antennas at first. Then, a virtual polarization filter(VPF) is proposed to separate superposed returns caused by multiple transmitted waveforms based on detection on the polarized parameters via particle swarm optimizer(PSO).Compared with the conventional matched filter to separate the orthogonal waveforms, it is shown that the coupling noises can be significantly suppressed by the proposed VPF-based method and the orthogonality is not necessary among different transmitting waveforms. Finally, experimental data experiments are also provided to demonstrate the effectiveness of the proposed method.

关键词： multiple-input and multiple-output synthetic aperture radar(MIMO-SAR) orthogonal waveforms virtual polarization filter(VPF) part

Parameter estimation for SAR moving target in complex image domain

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Science China(Information Sciences) 2010年第4期53卷 854-866页

作者： ZUO Yu, XU Jia*, peng yingning & XIA XiangGen Department of Electronic Engineering, Tsinghua University, Beijing 100084, China Department of Electronic Engineering Tsinghua University Beijing China

Based on the proposed parametric model of SAR ground moving target in the complex image domain, this paper derives the Cramer-Rao bounds (CRB) for the unknown model parameters estimation and obtains the inherent limitations for the moving target motion estimation in the SAR complex image domain. Firstly, the relationships are analyzed among the estimation performance and the target’s scattering intensity, Doppler parameters, motion parameters, as well as the power spectra of the target and the clutter. Furthermore, the parameter estimation performance is compared in the signal domain and the complex image domain (CID) to draw some useful conclusions. Besides, the reduction resolution processing is proposed to improve the parameter estimation, and its performance improvement is also presented with analytic expressions. For the homogeneous background, it is shown that the accurate parameter estimation and azimuth location may be realized for SAR ground moving target in the complex image domain. Finally, some numerical experiments are provided to demonstrate the effectiveness of the proposed methods.

关键词： synthetic aperture radar (SAR) moving target complex image domain parameter estimation Cramer-Rao bound (CRB) reduce resolution processing (RRP)

An Approach to Radar Netting

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An Approach to Radar Netting