Galileo短时突发搜救信号载波跟踪的锁相环设计

Design of PLL in the Carrier Tracking of Galileo Short-time Search and Rescue Burst Signal

Galileo搜救信号转发器搭载于Galileo导航卫星,能实现对全球遇险用户信号的转发,这种搜救信号具有突发、短时的特点,一般的F/PLL跟踪环无法对其进行有效的载波跟踪并完成解调。文中提出一种利用载波辅助的锁相跟踪方法,通过理论分析和MATLAB仿真可知,此锁相环能在约50m s内达到同步,可以有效地完成Galileo搜救信号的解调。

The Galileo search and rescue signal transmitter is carried on the Galileo navigation satellite,which can transmit the global distress user signal to the ground,it is a burst and short-time signal,so the carrier tracking and demodulation cannot be effectively completed by the common F/PLL tracking loop.This paper presents a PLL tracking method combined with carrier assistance.According to the result of theoretical analysis and MATLAB simulation,we can see that this loop can achieve synchronization in about 50ms,which could effectively finish the demodulation of Galileo search and rescue signal.