# An Anti-Interrupted-Sampling Repeater Jamming Method Based on Simulated Annealing–2-Optimization Parallel Optimization of Waveforms and Fractional Domain Extraction

## TL;DR

This paper introduces a new radar jamming method using optimized waveforms and fractional domain extraction to improve anti-jamming performance in complex environments.

## Contribution

A novel anti-interrupted-sampling repeater jamming method using SA-2opt waveform optimization and fractional domain extraction is proposed.

## Key findings

- The optimized waveform achieves sub-pulse orthogonality and autocorrelation sidelobe levels as low as -20.7dB.
- The proposed method effectively suppresses jamming even at high jamming-to-signal ratios.
- Simulation experiments confirm the effectiveness of the optimized waveform and anti-ISRJ performance.

## Abstract

Faced with increasingly complex electronic jamming environments, intra-pulse agility has become a primary method of anti-interrupted-sampling repeater jamming (ISRJ) for radar systems. However, existing intra-pulse agile signals suffer from high autocorrelation sidelobe levels and limited jamming suppression capabilities. These issues restrict the performance of intra-pulse agile signals in complex electromagnetic environments.This paper proposes an anti-interrupted-sampling repeater jamming method based on Simulated Annealing–2-optimization (SA-2opt) parallel optimization of waveforms and fractional domain extraction. Firstly, the proposed method employs the SA-2opt parallel optimization algorithm to optimize the joint frequency and chirp rate encoding waveform. Then, the received signal is subjected to the fractional Fourier transform (FrFT) and inverse transform to extract the target signal. Finally, jamming detection is conducted based on the multi-dimensional features of the pulse-compressed signal. After this detection, a time-domain filter is constructed to achieve jamming suppression. The optimized waveform exhibits the following advantages: the sub-pulses are orthogonal to each other, and autocorrelation sidelobe levels are as low as -20.7dB. The method proposed in this paper can achieve anti-ISRJ in the case of a high jamming-to-signal ratio (JSR). Simulation experiments validate both the effectiveness of the optimized waveform in achieving low autocorrelation sidelobes and the anti-ISRJ performance of the proposed method.