基于IIR陷波器级联的卫星导航接收机的干扰抑制性能

On Interference Suppression of IIR Notch Filters Cascade in Satellite Navigation Receivers

针对卫星导航接收机在抑制一定带宽干扰时的局限性,提出了2种直接型IIR陷波器的级联抑制算法,分别为陷波器串行级联和陷波器高阶级联.首先,分析了1阶复数型IIR陷波器和2阶直接型IIR陷波器的陷波特性,将低阶IIR陷波器与高阶IIR陷波器的特点进行比较.然后,对2种级联方式分别进行干扰抑制以及输出信干噪比的仿真,得出2种级联方法的更优算法.理论分析和仿真实验证明,2种陷波器级联算法均可以抑制一定带宽干扰,而陷波器串行级联的性能要优于陷波器高阶级联.此外,由信号的输出信干噪比探讨了干扰带宽、陷波带宽和陷波器级联个数三者之间的关系,从硬件设计和节约资源的角度来选择陷波器级联的个数.采用时域IIR陷波算法对干扰进行抑制,通过仿真验证算法的有效性.

Considering the limitation of the satellite navigation receiver in the suppression of interference with certain bandwidth,two kinds of direct IIR notch cascade suppression algorithm are proposed,namely tively notch filter serial concatenation and notch filter high class association.First,the notch characteristics of first order complex IIR notch filter and two order direct IIR notch filter are analyzed,and the characteristics of high order direct IIR notch filter and low order direct IIR notch are compared.The interference suppression simulation and the signal to interference plus noise ratio（SINR）simulation are respectirely carried out for the two cascade modes,and a better algorithm of two cascade methods are obtained.Theory analysis and experimental results of the experiment show that the two algorithms can suppress the interference of a certain bandwidth,and the performance of the notch filter is better than that of the notch filter.In addition,the relationship between interference bandwidth,notch bandwidth and trap number of cascade from the perspective of SINR,and the appropriate number of notch filters is selected from the per-spective of hardware design and resource saving.In order to form an adaptive interference suppression algorithm,the time domain IIR notch algorithm is used to suppress the interference,and the effectiveness of the algorithm is verified by simulation.