Abstract:

With the increasing intensity of radar electronic warfare and the growing complexity of practical electromagnetic battlefields, there is an urgent need to enhance the suppression capability against intermittently sampled repeater jamming (ISRJ) under more challenging echo signal environments. This study proposes an amplitude preprocessing-based ISRJ suppression method. Prior to filtering analysis, envelope detection is first performed on the amplitude of jamming-contaminated echo signals. Through analyzing the variation characteristics of envelope differential values, jamming-free segments are accurately extracted. Subsequently, amplitude compression is implemented on the contaminated signals based on the amplitude characteristics of these clean segments. Finally, energy analysis-based frequency-domain filtering is applied to the preprocessed echo signals. Multiple simulation experiments are conducted to validate the algorithm's ISRJ suppression performance under various signal-to-noise ratio (SNR) and interference-to-signal ratio (ISR) scenarios. Theoretical analysis and simulation results demonstrate that the proposed algorithm significantly enhances radar systems'ISRJ suppression capability. Under low SNR (5dB) and low JSR (5dB) conditions, the signal-to-interference ratio improvement factor in pulse compression results exceeds 30dB. In high SNR (10dB and 20dB) and high ISR (10dB and 20dB) scenarios, this improvement factor surpasses 55dB, showing markedly superior performance compared with two classical algorithms. The proposed algorithm demonstrates strong engineering practicality and provides valuable insights for developing novel intra-pulse deception jamming suppression techniques. It offers significant reference value for both the engineering development of countermeasure prototypes and the implementation of electronic counter-countermeasure tactics.

Key words: interrupted sampling repeater jamming, jamming suppression, envelope analysis, energy detection, linear frequency modulation