针对全球导航卫星系统(global navigation satellite system,GNSS)信号体制评估过程中,多径误差包络评估方法给出了多径误差的上界,并没有反映反射信号载波和子载波相位引入的码跟踪误差问题,提出了一种码跟踪多径误差非包络评估方法。该方法将反射信号的码相位延时映射到载波和子载波相位延时,为码跟踪多径误差提供了准确的理论值,而且避免了多径误差包络方法求包络曲线的过程。给出了该方法的理论表达式,对BPSK、AltBOC、MBOC和BOC信号进行了多径性能仿真,并与多径误差包络评估方法进行了对比。理论和仿真结果表明,本文方法能准确的估计码跟踪多径误差,为GNSS信号多径误差测量值提供有效的理论指导。
In the process of global navigation satellite system(GNSS)signal structural assessment,multipath error envelope gives the upper bound of multipath error,but it can not effectively reflect code tracking multipath error caused by the carrier and subcarrier phase of reflected signal.To solve this problem,a code tracking multipath error non-envelope assessment method is proposed.In the proposed method,the code phase delay is mapped to carrier and subcarrier phase to get an accurate theoretical code tracking multipath error value.This approach also avoids calculation of the envelope curve as found in the multipath error envelope analysis method.The theoretical expression of the proposed method was derived and a multipath rejection performance experiment simulation was performed for BPSK,AltBOC,MBOC and BOC.The multipath error envelope and proposed method were compared.The theoretical and simulated results show that the proposed method can be used to assess code tracking multipath error more accurately,and provides effective theoretical guidance for dealing with GNSS signal multipath error.