卫星导航接收机时域窄带干扰抑制滤波器设计与性能分析

针对卫星导航接收机时域窄带干扰的有效抑制问题，本文首先给出二阶格型IIR陷波器参数设计方法，通过陷波带宽的定量调整，既可以有效抑制窄带干扰，又可以降低卫星信号的失真；其次推导了二阶IIR格型陷波器相关输出信干噪比改善因子的闭合表达式，该表达式相比干扰抑制后信干噪比的改善，更为直观地反映了陷波器对卫星导航信号的影响。理论分析和仿真实验，二阶格型IIR陷波器相关输出信干噪比改善因子与陷波器的带宽参数有关，而与陷波频率无关，且二阶格型IIR陷波器的性能优于最优线性预测Wiener滤波器、最优线性插值Wiener滤波器、五系数FIR滤波器以及二阶直接型IIR陷波器。 

Research on the Performance of Filters Narrowband Interference Suppression in Satellite Navigation Receivers

In order to suppress the narrowband interferences effectively in the design of satellite navigation receivers, the method of parameter design of IIR lattice notch filter is introduced. According to this design rule, the notch bandwidth can be adjusted quantificationally, which minimizes the distortion of the signal in the full suppression of narrow-band interferences. Then, the closed-form expression of Signal to Interference and Noise Ratios (SINR) improvement of correlation of IIR lattice notch filter is derived. Compared to the normal SINR improvement, the SINR improvement of correlation is more intuitionistic to express the distortion of the signal. Theory analysis and results of the experiment show that the SINR improvement of correlation of IIR lattice notch filter is the function of notch bandwidth with no relationship with notch frequency. And IIR lattice notch filter outperforms the optimal Wiener filters, the five coefficients FIR filter and the direct-form IIR notch filter in the suppression of narrowband interferences.