基于FrFT的差分跳频通信LFM干扰抑制算法

针对差分跳频通信系统抗LFM干扰能力不足的问题,利用差分跳频信号和LFM干扰信号调频斜率参数的不同,通过估计采样信号中LFM干扰信号的调频斜率K和旋转阶次α参数,结合分段、参数估计和均值处理提高估计精度,进一步在采样信号的分数阶时频域二维参数平面(α,μ)中利用LFM干扰信号频带外的平面均值替代LFM信号成分,实现对差分跳频通信中LFM干扰信号的抑制。仿真结果表明,该算法可有效抑制差分跳频信号中LFM干扰信号,提高信噪比约11 d B。

A Method of LFM Interference Suppression for DFH Communication Based on FrFT

Direct to the poor ability of DFH Communication System to anti LFM interference. Using the different slope parameters of FM between the DFH signals and LFM signals,the frequency modulation slope K and the rotating order 琢 of LFM interference signal are estimated. The estimation accuracy is improved by combining with the section and mean treatment. Furthermore,the LFM signal components in the fractional frequency domain dimensional parameter plane (琢,滋) are replaced by using the mean plane outside the LFM interference signal frequency band. The LFM interference signal is suppressed in DFH communication. The simulation results show that the algorithm can effectively mitigate LFM interference in DFH communication to improve the SNR about 11 dB.