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.