Interference Countermeasure System Based on Time–Frequency Domain Characteristics

We investigate the issue of combating interrupted-sampling repeater jamming (ISRJ). Due to the advantages of miniaturization, lightweight, and flexibility, the ISRJ poses a great menace to radar performance through the fast sampling and forwarding of radar signals. Given this problem, we propose an electronic counter-countermeasure (ECCM) system based on the time–frequency domain. The system mines the information of radar echoes using de-chirping processing and the short-time Fourier transform (STFT). We introduce a binarization algorithm to achieve noise suppression and utilize two different features to guarantee the correct rate of target signal extraction. Simulation experiments show that our system can be effective against ISRJ. Moreover, our system still exhibits good interference suppression performance under the condition of multiple jammers, which effectively enhances the anti-jamming capability of the radar.