选取环路切换策略的高动态载波跟踪算法研究

摘要

针对基于环路切换的传统GPS跟踪环路,会因为载体运动背景的复杂性而出现环路切换频繁,造成环路抖动和跟踪效果差的问题,提出了基于环路切换策略的高动态载波跟踪算法.该算法首先利用频率、相位判决器选择带有切换策略的子环路工作,然后利用切换策略模块去控制子环路对信号进行跟踪.仿真结果表明:载体在信号强度为45 dB·Hz,以5 g和10 g加速度分时间段做匀加速运动的场景下,基于环路切换策略的高动态载波跟踪算法能使得环路的切换次数和抖动现象明显减少,跟踪效果更佳.%Traditional GPS tracking is based on the loop switching.Because of the complexity of carrier motion background,the loop switching is frequent,resulting in the problem of loop jitter and poor trackin.To solve this problem,a high dynamic carrier tracking algorithm based on switching strategy is proposed.In this algorithm,the frequency and the phase decision devices are used to select the sub loop with the switching strategy.Then,the switching strategy module is used to control the sub loop to track the signal.The simulation results show:when the carrier signal strength is 45 dB · Hz and a uniformly accelerated motion scene is 5 g and 10 g of acceleration in different time intervals,the high dynamic carrier tracking algorithm based on switching strategy can significantly reduce the number of switching and jitter of the loop,and a better tracking results is obtained.