DRFM jamming suppression for radar exploiting linear frequency modulation transmission

Digital radio frequency memory (DRFM) jamming is difficult to eliminate if it enters a radar system from the main lobe. A novel processing scheme for radar using linear frequency modulation waveform is proposed to accomplish target detection in asynchronous false target scenarios in accordance with the incoherent characteristic of the jamming signals. The technique of fractional Fourier transformation is adopted to transform the received signals with different time delays into single frequencies, then the target is estimated by a type of modified multiple signal classification approach. The difference of the estimated frequencies among the multiple transmitting period is used to discriminate the true and false echoes. In the end, order statistic constant false alarm rate approach is applied to target detection. The results of computer simulations show that the performance of the proposed scheme is superior to the conventional pulse compression processing in radar.