摘要
载波跟踪的目的是尽力使复制的载波信号与接收到的信号保持一致,从而能够很好地剥离卫星信号中的载波。因此,载波跟踪环路的跟踪精度很大程度决定了最后的定位测量精度。考虑到卫星等载体的高动态性带来的多普勒频移,跟踪环路需要同时具有较好跟踪精度和动态性能。因此,环路需要同时利用锁频环对信号具有较好的动态适应性和锁相环对信号具有较好的跟踪精度的特点。首先分析了锁频环和锁相环的原理,基于此采用了基于阈值调整的二阶锁频环辅助三阶锁相环的方法,最后利用Matlab对该算法进行仿真。结果表明跟踪环路能够较快地对信号进行跟踪的同时也具有较好的跟踪精度。
The purpose of carrier tracking is to make the duplicated carrier signal consistent with the received signal,so as to strip the carrier from the satellite signal.Therefore,the tracking accuracy of the carrier tracking loop determines the final positioning accuracy to a large extent.Considering the Doppler frequency shift caused by the high dynamic characteristics of satellites,the tracking loop requires good dynamic performance while also having good tracking accuracy.Therefore,the loop needs to simultaneously utilize the characteristics of Frequency-Locked Loop(FLL)with good dynamic adaptability to the signal and Phase-Locked Loop(PLL)with good tracking accuracy to the signal.The theory of FLL and PLL is analyzed,and based on this,adopts a method of using a second-order FLL assisted by a third-order PLL based on threshold adjustment.Finally,the algorithm is simulated by Matlab.The results show that the tracking loop can track the signal faster and has better tracking accuracy.
作者
王宇琦
张佩华
WANG Yuqi;ZHANG Peihua
出处
《现代导航》
2024年第2期97-101,共5页
Modern Navigation
关键词
载波环路
锁相环
锁频环
Carrier Loop
Frequency-Locked Loop
Phase-Locked Loop
