在非高斯背景和没有辅助数据的条件下,研究了高分辨率雷达分布式目标的自适应检测问题。首先采用有序检测理论和协方差矩阵的迭代估计方法粗略估计散射点集合,进一步利用迭代估计方法获得协方差矩阵的近似最大似然估计,提出了无需辅助数据的自适应检测器(ADWSD)。ADWSD在非高斯背景下具有近似恒虚警率特性,且检测性能远好于修正的广义似然比检测器。仿真分析表明,随着杂波尖峰的增加,ADWSD的检测性能得到提高,且对不同的杂波相关性具有很好的鲁棒性。
The high resolution radar target echoes can be referred to as a distributed target. In the non-Gaussian background, the adaptive detection of a distributed target is investigated without secondary data. Firstly, the set of target scatterers are estimated roughly by means of the order statistics detection theory and the recursive estimator of covariance matrix. Then, an approximately maximum likelihood estimate of the covariance matrix is acquired by the recursive estimator. Furthermore, an adaptive detector without secondary data(ADWSD)is derived for the distributed target. The proposed detector is almost of constant false alarm rate for a non-Gaussian clutter. In addition, the ADWSD performs much better than the existing detector of modified generalized likelihood ratio test. Finally, the simulation results show that, as the clutter spikiness increases, the detection performance of ADWSD is improved, especially for the low signal-to-clutter ratio scenarios; and it is also robust with respect to different correlations of clutter.
[1] 简涛, 何友, 苏峰, 等. 小波变换在雷达信号检测中的应用 [J]. 海军航空工程学院学报, 2006, 21(1): 121-126. Jian Tao,He You,Su Feng, et al. Overview on radar signal detection with wavelet transform [J]. Journal of Naval Aeronautical and Astronautical University, 2006, 21(1): 121-126. (in Chinese)
[2] 朱兆达, 丘振明, 张戌宝. 非参量量化秩检测器的性能研究 [J]. 航空学报, 1989, 10(3): 192-197. Zhu Zhaoda, Qiu Zhenming, Zhang Xubao. Study on performance of nonparametric quantized rank detectors [J]. Acta Aeronautica et Astronautica Sinica, 1989, 10(3): 192-197. (in Chinese)
[3] 简涛, 何友, 苏峰, 等. 一种基于小波变换的信号恒虚警率检测方法 [J]. 信号处理, 2006, 22(3): 430-433. Jian Tao, He You, Su Feng, et al. Signal CFAR detection method with wavelet transform [J]. Signal processing, 2006, 22(3): 430-433. (in Chinese)
[4] Wehner D R. High-resolution radar [M]. Boston: Artech House, 1995: 15-21.
[5] Robey F C, Fuhrmann D R, Kelly E J, et al. A CFAR adaptive matched filter detector [J]. IEEE Transactions on Aerospace and Electronic Systems, 1992, 28(1): 208-216.
[6] Gerlach K, Steiner M J. Adaptive detection of range distributed targets [J]. IEEE Transactions on Signal Processing, 1999, 47(7): 1844-1851.
[7] 简涛, 苏峰, 何友, 等. 一种针对拖尾噪声的鲁棒神经网络信号检测算法[J]. 电子与信息学报, 2007, 29(8): 1864-1867. Jian Tao, Su Feng, He You, et al. A detection algorithm of robust neural network for heavy-tailed noise [J]. Journal of Electronics & Information Technology, 2007, 29(8): 1864-1867. (in Chinese)
[8] Yao K. A representation theorem and its applications to spherically invariant random processes [J]. IEEE Transactions on Information Theory, 1973, 19(5): 600-608.
[9] Papoulis A, Pillai S U. Probability, random variables and stochastic processes[M]. 4 ed. New York: McGraw-Hill, 2002: 65-70.
[10] Van T H L. Detection, estimation, and modulation theory, part I: detection, estimation, and linear modulation theory [M]. New York: Wiley, 2001: 127-135.
[11] Kelly E J. An adaptive detection algorithm[J]. IEEE Transactions on Aerospace and Electronic Systems, 1986, 22(1): 115-127.
[12] Rangaswamy M. Statistical analysis of the nonhomogeneity detector for non-Gaussian interference backgrounds [J]. IEEE Transactions on Signal Processing, 2005, 53(6): 2101-2111.
[13] Gini F, Greco M. Covariance matrix estimation for CFAR detection in correlated heavy tailed clutter [J]. Signal Processing, 2002, 82(12): 1847-1859.
[14] 简涛, 何友, 苏峰, 等. 非高斯杂波下自适应雷达目标检测新方法[J]. 航空学报, 2010, 31(3): 579-586. Jian Tao, He You, Su Feng, et al. A novel adaptive radar target detector for non-Gaussian clutter[J]. Acta Aeronautica et Astronautica Sinica, 2010, 31(3): 579-586. (in Chinese)
[15] Gini F, Bordoni F, Farina A. Multiple radar targets detection by exploiting induced amplitude modulation[J]. IEEE Transactions on Signal Processing, 2004, 52(4): 903-913.
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