一种基于循环平稳特性的稳健的抗窄带干扰算法

A robust Method for NarrowBand Interference Suppression Based on Cyclostationarity Property

直扩系统中采用频移滤波器作为白化滤波器,利用了窄带干扰的循环平稳特性,可得到比传统线性时不变滤波器更好的抗干扰效果。当存在循环频率误差时,上述频移滤波器的性能将急剧下降。本文先分析循环频率误差导致滤波器恶化的原因,而后提出一种稳健的算法。仿真表明,本算法可以大大降低滤波器对循环频率误差的敏感性。

A narrowband interference suppression filter based on the frequency shift filter can achieve a better performance than that based on the conventional LTL filter in DSSS. However, the frequency shift filter gets severe performance degradation,when there is a small mismatch in the cyclic frequency error of the desired signal. This paper considers the behavior of the frequency shift filter in the presence of cyclic frequency error. Based on the theoretical analysis,we present a robust method to alleviate the performance degradation. Simulation results show this method would largely depress the sensitivity of frequency shift filter to cyclic frequency error.