基于同态滤波的GPS空时自适应处理补偿技术  

Homomorphic filtering based compensation technique for space-time adaptive processing in GPS

作　　者：吴仁彪[1,2] 徐如兰[1] 卢丹[1] 

机构地区：[1]中国民航大学天津市智能信号与图像处理重点实验室,天津300300 [2]深圳大学ATR国防科技重点实验室,深圳518060

出　　处：《中国科学：物理学、力学、天文学》2010年第5期554-559,共6页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：国家高技术研究发展计划(编号:2006AA12Z321);中国民用航空局科技基金(编号:MHRD0606)资助项目

摘　　要：GPS系统工作在有干扰的环境中时,近处干扰与远处卫星间巨大的功率差异导致GPS信号的扩频增益不足以抵抗干扰的影响.空时自适应处理技术已成为GPS接收机抗干扰研究的热点,相比于空域自适应阵列处理可以有更多的抗干扰自由度,消除多个强的宽带干扰及近场的宽带干扰多径.但是由于空时自适应处理的结构使之在处理带宽上不能有一致的频率响应,造成GPS信号的相关函数的相关峰产生畸变,降低接收机的定位精度.本文分析了空域与空时域自适应阵列处理抵抗干扰的性能,对空时自适应处理的原理及影响卫星信号的原因进行了研究,为了恢复出期望的卫星信号,提出一种基于同态滤波均衡原理的方法,补偿由空时自适应处理造成的对卫星信号的影响.仿真结果表明了所提出的方法的有效性.When Global Positioning System （GPS） operates in the presence of hostile jamming, vast power difference between nearby jammers and distant satellite sources makes the spread-spectrum gain of the GPS signal inadequate for anti-jamming protection. Space time adaptive processing （STAP） can be used to remove hostile jammers for the GPS receiver, especially in the presence of multiple strong interferes plus multipath. However, while suppressing the hostile jammers, the STAP filter can also bring in distortion to the GPS signal because it does not have a uniform frequency response across the operating band, which would dramatically reduce the accuracy of the users’ position. In this paper, the performance of space-only and space-time adaptive processing is analysed, and the reason of the distortion caused by STAP is explained. a new method based on the homomorphic filtering is proposed to compensate the distortion caused by the STAP filter. Simulation results show that the proposed algorithm is feasible and effective.

关 键 词：全球定位系统 空时自适应处理 同态滤波 自适应阵列 

分 类 号：TN967.1[电子电信—信号与信息处理]