基于锁频环与锁相环相结合的载波跟踪技术  

Carrier Tracking Based on Combination of FLL and PLL

作　　者：许志鹏[1] 崔琛[1] 余剑[1] 

机构地区：[1]电子工程学院信息系,合肥230037

出　　处：《电讯技术》2012年第4期558-561,共4页Telecommunication Engineering

摘　　要：针对锁频环与锁相环各自在载波跟踪方面的优点与不足,设计了一种基于Costas环的锁频环与锁相环相结合的载波跟踪环路。基于锁频环与锁相环各自锁定时残余频差与残余相差都接近于0的原因,提出了mc、mpe两个阈值,当阈值满足设定的条件时,载波跟踪环路自适应地选择相应的工作状态。仿真结果表明,在阈值达到设定的条件时环路能够正确地实现工作状态的转换,在多普勒频移为固定值以及阶跃函数时能进行准确的跟踪,达到了设计目的。A carrier- tracking loop is designed on the base of respective advantages and disadvantages of FLL and PLL on carrier - tracking. Two thresholds（ mc and mpe ） are proposed according to the reason that when FLL and PLL catch the frequency, the rest of frequency error and phase error are approximately equal to zero. When the two thresholds satisfy the given conditions, the loop will choose work state automatically.＂ Simulation shows that when the two thresholds satisfy the given conditions, the loop can switch work state correctly, and carrier can all be tracked whenever the Doppler frequency is a constant value or a step equation of time, and the aim of design is realized.

关 键 词：相干接收机 载波跟踪 锁频环 锁相环 

分 类 号：TN973.3[电子电信—信号与信息处理]