【作者】 曹晶烨； 支琤；

【Author】 Jingye Cao~1,Cheng Zhi~2 1.Department of Electrical Engineering,Shanghai Jiaotong University,Shanghai 200240,China 2.Department of Electrical Engineering,Shanghai Jiaotong University,Shanghai 200240,China

【机构】 上海交通大学电子工程系；

【摘要】 在卫星导航技术中,码跟踪环(Code Tracking Loop)用于同步每个卫星的直接扩频序列信号(DSSS),之后延时锁定环(DLL)锁定信号时延,估计出每个卫星的伪距离。卫星末级的功率放大器具有非线性效应,非线性使得信号产生新的频谱分量,从而信号频谱展宽,影响码跟踪环的精度,造成定时误差,致使最后产生定位误差。本文从功率放大器入手,首先研究功率放大器的非线性效应与数学描述方法。之后推导在某特定非线性功率放大器模型下,经功放输出之后的信号的频谱数学表达式。然后,将失真信号频谱表达式与原信号频谱做比较,计算功放模块非线性所造成的码跟踪环误差,最后得出,功率放大器的非线性效应与卫星导航定位误差之间的关系。更多还原

【Abstract】 In satellite navigation technology,code tracking loops are used to synchronize direct sequence spread spectrum signals on each satellite,after which delay lock loops(DLL) get delay of the signal and estimate pseudo-range of each satellite.Power amplifiers on satellites have nonlinear effects that produce new frequency components,causing spectrum regrowth and thus influencing the accuracy of code tracking loops which leads to position errors.This paper studied nonlinear effects and mathematical characterization of power amplifiers,derived signal spectrum expressions under certain power amplifier model,and finally get the relation between power amplifier nonlinear effects and position errors by comparing the spectrum of the original signals and the distorted signals.更多还原