基于移频干扰的成像算法抗干扰性能分析

The Analyse of SAR Imaging Algorithm Anti-Jamming Performance Based on Representative Shift-Frequency Jamming

本文针对RD和CS两种成像算法处理流程和方法的差异,分析了两种算法在移频干扰情况下的成像处理增益,并推导了两种算法的信干比处理增益公式.理论分析结果表明,在距离向采样率与SAR信号带宽相当的情况下,RD成像算法对移频干扰的抑制能力强于CS算法;在方位向过采样情况下,RD算法由于采用两维匹配处理从而获得比CS算法大的信干比处理增益,若对信号进行方位向滤波处理后,CS算法的对移频干扰的抗干扰能力与RD算法相当.最后,通过计算机仿真验证了本文的理论分析和结论.

In according with the difference of RD algorithm and CS algorithm＇ processing flow and calculation method,this paper analyzed processing gain of two algorithms in the environment of shift-frequency jamming,and deduced formulas of the SJR processing gain about two algorithms.The academic analyzing result demonstrates that the restrainable capability of RD algorithm about shift-frequency jamming is stronger than CS algorithm if the sampling rate of distance dimension is equivalent with the band width of the signal.And at the condition of the over sampling rate about azimuth dimension,the SJR processing gain of RD algorithm is larger than CS algorithm because of two dimension matching fliter of RD algorithm.If the over sampling signal is filtered in azimuth dimension,the SJR processing gain of CS algorithm is uniform with the RD algorithm.Finally,the computer simulation testifies the validity and availability of theory analyzing results and conclusion.