一种大频偏抗边带错锁的数字锁相环设计

在小卫星遥测系统中,地面站接收信号伴随着大多普勒频偏,副载波会落入主载波的多普勒频偏的范围之内,数字锁相环对主载波的跟踪必须避免边带错锁。提出一种新的数字锁相环结构,通过频谱分析辅助,初始频差和环路带宽被减小,副载波不会落入环路带宽之内;在环路中采用cic低通滤波下抽样滤除副载波分量,副载波对锁相环的影响得以消除。仿真结果表明,该锁相环在大频偏情况下能够很好地消除边带错锁。在实际的地面站遥测接收机中,该锁相环也能够很好地工作。

Design of DPLL for Anti-False-Lock with Large Frequency Offset

The signal received from the ground station in the micro-satellite telemetry system is usually with large Doppler frequency offset,and the vice carrier signal will lap over the Doppler frequency offset of the main carrier signal.DPLL(Digital Phase-Locked Loop) tracking the main carrier signal must avoid the false-lock on the vice carrier signal.This paper designs a DPLL with new structure.The frequency offset and the loop bandwidth are degraded with the aid of spectrum analysis.Then the vice carrier will no...