最小均方误差检测器对扩频系统中窄带干扰的抑制性能分析

Performance of Minimum Mean Square Error Detector against Narrowband Interference in Spread Spectrum Systems

本文首先说明当码元间隔内的码片数目与扩频序列周期相等时,直接序列扩频(DSSS)系统中最小均方误差(MMSE)意义下的最优滤波器也是最小误码率意义下的最优滤波器,因而能很好地抑制大多数干扰样式。本文具体分析了最小均方误差检测器对音频干扰以及自回归干扰的抑制性能,给出了详细的推导过程以及结论。

This paper proves that the Wiener filter, optimized in the minimum mean square error (MMSE) sense, is also the optimum filter in the minimum bit error rate (MBER) sense when the period of the spreading sequence is equal to the number of chips per symbol. Thus, the MMSE detector can effectively suppress many types of interference signals. Closed-form expression for its performance against two types of narrowband (NBI), multitone signal and autoregressive(AR) signal are derived.