直扩通信中时变幅度LFM干扰的抑制

Suppression of Time-varying Amplitude LFM Interference in DSSS Communication

本文针对直扩通信中的时变幅度线性调频干扰,提出了一种基于分数阶Fourier变换的干扰抑制算法。该算法利用两个角度的分数阶Fourier功率谱和拟Newton迭代法进行参数估计,并在参数估计的基础上,采用分数阶Fourier域干扰分离法进行干扰抑制。与基于二维搜索参数估计的干扰抑制算法相比,该算法在保证干扰抑制性能的前提下,大大缩减了计算量。仿真结果表明,该算法可以在较大干信比范围内有效抑制时变幅度线性调频干扰。

This paper presents an interference suppression algorithm based on fractional Fourier transform in order to suppress time-varying amplitude LFM interference in Direct Sequence Spread Spectrum communication. The parameters are estimated via fractional Fourier power spectrum in two angles and Newton iterative method. Then, interference is suppressed through interference separation in fractional Fourier domain using estimated parameters. Compared with interference suppression algorithm based on two-dimensional searching, this algorithm has same performance and smaller amount of computation. Simulation results show that the algorithm can suppress time-varying amplitude LFM interference efficiently in large jamming-signal-rate range.