GPS接收机窄带干扰抑制新方法

Novel suppression method for narrow-band interference in GPS receiver

针对GPS接收机中常见的窄带干扰信号,提出了一种全数字式时域和频域相结合的窄带干扰抑制方法。首先将含有窄带干扰的时域GPS信号变换成频域信号,然后将此频域信号与自适应干扰判决门限比较获取干扰信号的中心频率和带宽,由此确定滤波器参数并设计时域滤波器。仿真结果表明与没有使用干扰抑制处理相比,当信干比SJR为-25dB、误码率BER为10E-4时,该方法可使Eb/N0改善4dB;与无干扰时的理论值相比,此时Eb/N0的恶化小于0.5dB。随着干扰强度的增加,该方法的干扰抑制效果更加明显。考虑到本方法的并行处理机制,这些结果表明该方法不但具有较好的抗干扰能力,而且具有较好的实时性。

A novel full digital method of narrow-band interference （NBI） suppression in GPS receiver was proposed with the combination of NBl suppression in both the time and frequency domain. By comparing the frequency domain signal transformed from the time-domain NBI GPS signal with an adaptive interference threshold, the center frequency and bandwidth of NBI signal were obtained, and a time-domain filter suppressing NBI was designed based on above parameters. The simulation results show that, by this method and for SJR= -25 dB and BER= 10E-4, the Eb/N0 of the receiver has 4 dB improvement compared to that without NBI suppression and 0.5 dB less worsening compared to the theory value without interference. With the increase of interference intensity, the method presents a better performance. Considering its parallel procession, these results show that the method can not only improve the performance of NBl suppression in GPS receiver, but also has a high real-time property.