接收机载波初始相位偏差变化特性分析

INVESTIGATION ON CHARACTERISTICS OF RECEIVER'S INITIAL PHASE BIAS CHANGE

根据接收机的设计和载波相位测量原理,分析了接收机频率综合、混频、数字下变频、跟踪环路等模块对载波相位测量的影响,建立了载波相位测量值和初始相位偏差的数学模型。利用导航信号源和接收机平台,通过实验验证了初始相位偏差的长期稳定性及其随卫星信号失锁、本地时间调整及开关机的变化特性。

Satellite and receiver＇s Initial Phase Biases（IPBs） have a significant influence on ambiguity resolution and convergence time of precise point positioning（PPP）.The current receiver IPB is experimentally confirmed to be different when the receiver is turned off and back on.However,its underlying characteristics are seldom investigated in available literatures.On the basis of receiver design and carrier phase measurement mechanism,the article analyzed the impacts of frequency synthesizer,mixer,digital down converter and tracking loop on carrier phase measurement generation.Meanwhile,the mathematical models of carrier phase measurement and IPB are derived.Finally,the receiver IPB＇s long-term stability and characteristics according to loss of lock,time adjust and power-on cycle are validated by experiment using navigation signal source and receiver platform.