A Method of Suppressing Folded Clutter in High PRF  Stepped Frequency Radar

A method is proposed to suppress the folded clutter which is caused by high pulse repetition frequency (PRF) of stepped frequency radar. Firstly， the folded clutter outside the range processing interval is attenuated by the intermediate frequency (IF) bandpass filter in the receiver’s foreside. In order that the bandpass filter can reject the external folded clutter more effectively， the transmitted pulse envelope is designed. Secondly， the folded clutter within the range processing interval is further cancelled using high range resolution processing of the return signal on condition of specific waveform parameters. The method does not change the basic stepped frequency waveform or complicate the signal processing of stepped frequency radar. Therefore， it has the advantages of simpleness and effectiveness. Comparing with pulse Doppler (PD) radar， high PRF stepped frequency radar is better at suppressing folded clutter. Simulation results validate the correctness of the method.