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Parallel pipelined least-mean-square algorithm and its performance analysis

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Progress in Natural Science:Materials International 2002年第1期 71-74页

作者： SHANG Yong, WU Shunjun and xiANG Haige( Department of Electronics, Peking university, Beijing 100871, china key laboratory of radar signal processing, xidian university, xi'an 710071, china) Department of Electronics，Peking university，Beijing 100871，china key laboratory of radar signal processing，xidian university，xi'an 710071，china key laboratory of radar signal processing，xidian university，xi'an 710071，china Department of Electronics，Peking university，Beijing 100871，china

A novel parallel pipelined least-mean-square algorithm is proposed by introducing parallel processing into the pipelined least-mean-square algorithm. The algorithm presented in this paper has smaller pipelined delay, higher data throughput rate and faster convergence speed, as well as wider step size range in which the convergence behavior of the algorithm is maintained than the pipelined least-mean-square algorithm. It also exhibits some de-correlation effect for the correlated input sequence. These properties make it more suitable for the cases of higher order filter with faster convergence speed. In addition, it can also be used to simplify the hardware implementation of filters.

关键词： parallel processing adaptive filtering parallel pipelined least-mean-square algorithm performance analysis.

Multiary turbo code fitting for unitary space-time modulation and its MAP decoding algorithm

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Science china(Information Sciences) 2010年第12期53卷 2610-2619页

作者： ZHANG DaPeng 1,2,3,LU Ju 1,XU HongJi 1 & ZHANG xingYu 1 1 School of Information Science and Engineering,Shandong university,Jinan 250100,china 2 State key laboratory of Integrated Services Networks,xidian university,xi'an 710077,china 3 Department of Avionics Engineering,First Aeronautical College of the Air Force,xinyang 464000,china 1. School of Information Science and Engineering Shandong University Jinan 250100 China2. State Key Laboratory of Integrated Services Networks Xidian University Xi’an 710077 China3. Department of Avionics Engineering First Aeronautical College of the Air Force Xinyang 464000 China

Unitary space-time modulation(USTM) fits for rapid Rayleigh flat fading channels as it can realize wireless communication when neither the transmitter nor the receiver knows the channel state information(CSI).However,an intrinsic problem is that only when the signal-to-noise ratio(SNR) is high can it give an ideal bit error rate(BER) *** existing bit-wise processing scheme of the combination of turbo code and USTM improves the BER performance and results in an unacceptable calculation complexity,storage and time delay *** this paper,we propose a multiary processing scheme and its corresponding multiary MAP decoding *** results verify that our scheme can reduce the system complexity while keep a good BER ***,we present the first analysis of the reason for the BER performance deterioration of the combination scheme at low SNR with the help of the definition of USTM.

关键词： multiple-input multiple-output unitary space-time modulation turbo code MAP decoding diversity

ASIC DESIGN OF ADAPTIVE THRESHOLD DENOISE DWT CHIP

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Journal of Electronics(china) 2002年第1期19卷 1-7页

作者： Luo Feng Wu Shunjun Jiao Licheng ZhangLinrang(national key Lab. for radar signal processing, xidian university, xi’an 710071) national key Lab. for radar signal processing Xidian University Xi'an 710071

According to the relationship of wavelet transform and perfect reconstructive FIR filter banks, this paper presents a real-time chip with adaptive Dorioho’s non-linear soft-threshold for denoising in different levels of multi-scale space through rearranging the input data during convolving, filtering and sub-sampling. And more important, it gives a simple iterative algorithm to calculate the variance of the noise in interregna with no signal. It works well whether the signal or noise is stationary or not.

关键词： Wavelet transform Filter banks ASIC CPLD

radar HRRP RECOGNITION BASED ON THE MINIMUM KULLBACK-LEIBLER DISTANCE CRITERION

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Journal of Electronics(china) 2007年第2期24卷 199-203页

作者： Yuan Li Liu Hongwei Bao Zheng key Lab for radar signal processing Xidian University Xi＇an 710071 China

To relax the target aspect sensitivity and use more statistical information of the High Range Resolution Profiles (HRRPs), in this paper, the average range profile and the variance range profile are extracted together as the feature vectors for both training data and test data representa-tion. And a decision rule is established for Automatic Target Recognition (ATR) based on the mini-mum Kullback-Leibler Distance (KLD) criterion. The recognition performance of the proposed method is comparable with that of Adaptive Gaussian Classifier (AGC) with multiple test HRRPs, but the proposed method is much more computational efficient. Experimental results based on the measured data show that the minimum KLD classifier is effective.

关键词： High Range Resolution Profile (HRRP) Automatic Target Recognition (ATR) Kullback-Leibler Distance (KLD) Adaptive Gaussian Classifier (AGC)

FREQUENCY-CODED OPTIMIZATION OF HOPPED-FREQUENCY PULSE signal BASED ON GENETIC ALGORITHM

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Journal of Electronics(china) 2005年第1期22卷 25-33页

作者： LiuZheng MuXuehua nationalkeyLab.forradarsignalprocessing XidianUniversityXi＇an710071China

The Frequency-Coded Pulse (FCP) signal has good performance of range and Doppler resolution. This paper first gives the mathematical expression of the ambiguity function for FCP signals, and then presents a coding rule for optimizing FCP signal. The genetic algorithm is presented to solve this kind of problem for optimizing codes. Finally, an example for optimizing calculation is illustrated and the optimized frequency coding results are given with the code length N=64 and N=128 respectively.

关键词： Frequency-Coded Pulse(FCP) Ambiguity function Genetic Algorithm(GA)

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低脉冲重复频率合成孔径激光雷达成像

光电子．激光 2011年第5期22卷 772-777页

作者：郭亮曾晓东邢孟道唐禹西安电子科技大学技术物理学院陕西西安710071 西安电子科技大学雷达信号处理国家重点实验室陕西西安710071

为提高合成孔径激光雷达(SAL)的分辨率,从激光脉冲调制与脉冲重复频率(PRF)的矛盾入手,提出了一种沿方位向放置多个望远镜接收的系统设计方法,利用空间自由度解决由于较低PRF带来的方位模糊问题。分析了SAL系统由于平台连续运动的影响(... 详细信息

为提高合成孔径激光雷达(SAL)的分辨率,从激光脉冲调制与脉冲重复频率(PRF)的矛盾入手,提出了一种沿方位向放置多个望远镜接收的系统设计方法,利用空间自由度解决由于较低PRF带来的方位模糊问题。分析了SAL系统由于平台连续运动的影响(表现为多普勒频移项),提出了多普勒平移补偿方法。通过仿真实验验证了本文所提系统设计的正确性,和所给方法的有效性,有效地解决了方位模糊问题。

关键词：合成孔径激光雷达(SAL) 脉冲重复频率(PRF) 方位模糊成像

A NOVEL DETECTOR FOR UPLINK CDMA SYSTEM WITH UNKNOWN INTERFERENCE

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Journal of Electronics(china) 2003年第4期20卷 289-292页

作者： Wu Lili Huang Hui Liao Guisheng (key Lab for radar signal processing, xidian university, xi’an 710071) key Lab for radar signal processing Xidian University Xi'an 710071

In this letter, the detection of asynchronous DS-CDMA signal with multipath fading and interference from neighboring cells is studied. A novel multiuser detector based on Gibbs sampler is proposed, in which Gibbs sampler is employed to perform the Bayesian multiuser detection according to the linear group-blind decorrelator output. Since Gibbs sampler is dependent of parameter estimation that can be improved by the output of the detector, an enhanced Gibbs sampler based detector using the improved parameter estimation is put forward. The novel multiuser detection technique has the advantages of high performance and wide applications. Computer simulations show its effectiveness.

关键词： Gibbs sampler Asynchronous DS-CDMA signal Bayesian multiuser detection Parameter estimation

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机载前视阵雷达距离模糊杂波抑制新方法

系统仿真学报 2009年第22期21卷 7338-7341页

作者：李明廖桂生西安电子科技大学雷达信号处理国家重点实验室西安710071

提出了一种简单有效的机载前视阵抑制距离模糊杂波方法。该方法在对数据进行多普勒滤波之后向待检测距离区间的中心距离单元空域导向矢量空间投影,能够获得好的模糊杂波滤除性能,并且降低了计算量。计算机仿真实验结果表明了该方法在雷... 详细信息

提出了一种简单有效的机载前视阵抑制距离模糊杂波方法。该方法在对数据进行多普勒滤波之后向待检测距离区间的中心距离单元空域导向矢量空间投影,能够获得好的模糊杂波滤除性能,并且降低了计算量。计算机仿真实验结果表明了该方法在雷达回波存在误差的情况下具有稳健性。

关键词：机载前视阵雷达距离模糊投影空域导向矢量

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基于对比度最优准则的运动目标参数估计方法

系统仿真学报 2009年第19期21卷 6157-6160页

作者：蔚婧廖桂生西安电子科技大学雷达信号处理国家重点实验室 710071

在已检测出运动目标的基础上,提出了一种基于图像对比度最优准则的运动目标参数估计方法。该方法针对存在方位向速度的运动目标,以图像对比度作为评价标准,对运动目标的速度分量进行二维寻优,当图像对比度函数达到最大值时,得到运动目... 详细信息

在已检测出运动目标的基础上,提出了一种基于图像对比度最优准则的运动目标参数估计方法。该方法针对存在方位向速度的运动目标,以图像对比度作为评价标准,对运动目标的速度分量进行二维寻优,当图像对比度函数达到最大值时,得到运动目标的速度分量的精确估计值。经过仿真及实测数据验证,该方法能很好的估计出运动目标的运动参数,并且该方法的测速精度明显优于传统动目标测速方法。

关键词：合成孔径雷达运动目标检测参数估计对比度最优