基于已知传播模式数目的海杂波抑制方法研究  

Sea clutter suppression algorithm based on ionospheric propagation mode number

作　　者：李雪[1] 郭晓彤[1] 王岳松[1] 李吉宁[1] 

机构地区：[1]中国电波传播研究所,青岛266107

出　　处：《电波科学学报》2016年第4期700-706,共7页Chinese Journal of Radio Science

基　　金：国家自然科学基金青年基金(No.61302006);中国电科技术创新基金(JJ-QN-2013-28)

摘　　要：天波超视距雷达海杂波谱受电离层多模传播影响大幅展宽,需进行杂波抑制才可实现舰船目标检测,利用电离层返回散射探测可获得海杂波谱先验模式数目信息.针对常用的两种海杂波抑制方法——特征值分解法和循环对消法,仿真分析了传播模式数目识别准确性对海杂波抑制效果的影响.结果表明:若传播模式数目识别错误,则会造成目标漏检或虚警.在传播模式数目已知的前提下,利用仿真和试验数据研究了目标与一阶海杂波多普勒相对位置和多普勒分辨率对上述两种方法海杂波抑制效果的影响.目标与一阶海杂波越接近,海杂波抑制效果越差,当二者相对多普勒位置小于分辨率时,两种方法均失效;多普勒分辨率越低,海杂波抑制效果越差;目标与海杂波越接近,对多普勒频率分辨率要求越高.Since the sea clutter spectrum of due to the ionospheric multimode propagation, over-the-horizon radar（OTHR） always has large spreads the clutter suppression needs to be done for detection of ship targets. The information of a priori mode number for the sea clutter spectrum can be acquired via ion- ospheric backscatter sounding. The effects of the identification for propagation mode number on the sup- pression of sea clutter are simulated and analyzed based on two common methods of sea clutter suppres- sion, namely, the singular value decomposition （SVD） algorithm and the phase information of Fourier transform algorithm. The results show that target false-alarm or false-dismissal will occur if the identifica- tion of propagation mode number is not correct. Furthermore, the influence of the distance between the target and the first-order sea clutter and the Doppler resolution on the sea clutter suppression using the a- bove two methods is studied through both simulated and experimental data with the precondition of known propagation mode number, and consequently two conclusions are obtained. The first conclusion is that the closer the target is to the first-order sea clutter, the worse the suppression of sea clutter operates, and when the distance of the two is within the Doppler resolution range, neither of the two methods works. The second one is that the sea clutter suppression effect is poorer with the lower Doppler resolution, and closer distance between target and clutter will require higher Doppler {requency resolution.

关 键 词：天波超视距雷达海杂波谱 传播模式数目 奇异值分解法 循环对消法 

分 类 号：TN011.2[电子电信—物理电子学]