针对舰艇编队情况下线性调频脉冲体制雷达间同频干扰的问题,该文提出一种分数阶傅里叶域滤波处理与时域反异步处理相结合的干扰抑制方法。通过分数阶傅里叶域自适应滤波对与目标回波信号调频率不同的干扰信号做抑制处理,同时根据分数阶傅里叶变换的可逆性,逆变换到时域后采用相邻周期反异步方法进一步消除与目标回波信号调频率相同或相近的同频干扰。仿真试验表明,该方法相对传统方法能够有效抑制与目标回波信号调频率不同的同频干扰,同时对于在时域与目标回波信号完全重合或部分重合的干扰信号也有较好的抑制效果,干扰抑制处理增益达到29dB以上。该方法为提高同型雷达编队组网能力提供了设计参考。
An interference suppression method based on joint fractional Fourier domain and time domain is proposed in this paper, to solve the problem of co-channel interference caused by homo-type radars working in ship formation. The interferences with different chirp rate from echo signal can be eliminated at fractional Fourier domain, and because of the reversibility of fractional Fourier transform, the ones with similar chirp rate can be cancelled by against-asynchronism of adjacent periods at time domain. Computer simulation results show that interference suppression processing gain reaches 29 dB. This method presents technical support for the ElectroMagnetic Compatibility (EMC) research in the ship formation.