基于伪相关函数的BOC无模糊跟踪性能分析

BOC(Binary-Offset-Carrier)调制广泛应用于全球导航卫星系统中，但由于BOC自相关函数的多峰导致传统码跟踪环路存在模糊性。伪相关函数(Pseudo Correlation Function, PCF)方法在本地采用两个特殊的参考信号和非线性处理以获得无模糊的相关函数。根据一种PCF方法本地参考波形设计的充分条件，推导了其无模糊函数的数学形式，并着重分析了其跟踪和抗多径性能与本地参考波形的关系。仿真结果表明：该PCF方法解决了跟踪模糊问题，且随着参考信号的宽度因子增加，其跟踪精度逐步改善；该PCF方法对于中长延迟多径干扰抑制能力较好，宽度因子为0.5或1时，其多径误差最小。

Tracking Performance Analysis for BOC Signals Based on Pseudo Correlation Function Method

Binary-offset-carrier (BOC) modulation is widely used in the global navigation satellite system (GNSS). However, the autocorrelation function (ACF) of the BOC modulated signal has multi peaks, and may bring about ambiguity in traditional code tracking loop. The pseudo correlation function (PCF) method employs two special local signals and nonlinear processing to form a no side-peak function. The mathematical expressions of one PCF method are derived in this paper, then the performance analysis is given for different local reference pulse shapes. Simulations show that the PCF method is unambiguous, and with increase of the width factor of the local reference signal, the tracking accuracy gradually increases. And the PCF method is good in mitigating moderate and long multipath interferences, multipath error envelopes are the smallest when the width factors are 0.5 or 1.