动态和噪声环境下伪码和载波联合测距算法研究

Research on PN code and carrier tracking algorithm in dynamic and noise environment

在分析伪码和载波跟踪环性能的基础上,给出了跟踪环路的最优带宽.根据实时估计的信噪比动态的更新环路带宽,减小噪声带来的跟踪误差.针对载体的动态性利用AFC算法快速得到多普勒频率,并利用载波辅助伪码跟踪环路,可以在较窄的环路带宽下跟踪高动态的扩频信号,从而可以很好地抑制宽带噪声,提高跟踪精度.理论分析和仿真表明,该方法能有效改善环路的动态性能和跟踪精度,满足系统要求.

Based on the performance of PN code and carrier tracking loop, an optimal loop bandwidth is presented. By updating the optimal bandwidth based on SNR, tracking error decreases. Presented is an asynchronous forward-checking （AFC） algorithm that can attain Doppler shift rapidly when the receiver is operating in a dynamic environment. The new carrier auxiliary code-tracking loop operates in narrow bandwidths. Analysis and simulations show that the algorithm is efficient for improving precision of the tracking loop.