抗窄带干扰自适应能量判决门限频域滤波器的研究

Research on suppression of narrowband jammer using frequency domain filter with adaptive energy threshold

在扩频通信系统中,以频域自适应滤波器抑制窄带干扰的技术已经得到广泛应用,但是一般都视直扩信号的频谱为白色谱,即其频域各子带的能量判决门限被定为常数。结合直扩DS信号频谱的特征,应用自适应能量判决门限AET(adaptiveenergythreshold)算法动态地设定各子带的判决门限,借以提高其抗窄带干扰的系统性能。通过仿真证明:基于AET算法的频域自适应滤波器较常规频域自适应滤波器抑制窄带干扰能力有较大地提高。

The technologies of narrow-band interference suppressions by using a frequency domain filter were introduced widely in the DSSS (direct sequence spread spectrum) system. But the spectrum of DS (direct sequence) is supposed as the white spectrum, where thresholds of energy ruling are constant. According to the characteristic of the DS spectrum, AET adaptive energy threshold was used to decide the thresholds of energy ruling dynamically. The experiment proves that the performance of the adaptive frequency domain filter using AET is improved in the suppression of narrow-band interference.