星地非理想通道下的导航信号测距偏差分析

Effect of satellite-earth non-ideal channel analysis on code tracking bias

针对广义信道下伪码测距偏差与各部分通道测距偏差叠加值的等效性问题,研究星地叠加通道和部分通道特性对伪码测距偏差的影响,并对实际通道中伪距"分层"现象的成因展开分析。通道非理想特性会对导航信号伪码跟踪性能产生影响,综合考虑星地两端通道的非理想特性,通过对导航信号伪码跟踪函数和不同类型通道建模,研究了星地叠加通道和部分通道特性对伪码测距偏差的影响。结合几类典型星地非理想通道,利用软件接收机展开仿真验证。通过分析几类典型通道对伪码测距偏差的影响,解释了零基线双差观测量中伪距"分层"现象的成因。文中模型与相关分析方法可用于解释相关信号质量问题,并指导接收机通道的最优化设计。

The equivalent problem of the code tracking bias introduced by generalized joint channel channel were researched. The influence of the code tracking bias caused by the channel characteristics opart of the channel was studied. The possible causes of pseudorange layered in the actual channel were analyzed. The non-ideal characteristics ofthe channel afected the tracking performance of the navigation signal. The pseudo code tracking function and channel characteristics were modeledthe non-ideal characteristics of both the satellite channel and the receiver channel were considered. The influence of different channel characteristics on code tracking bias was analyzed. Simulation verification was carried out with a software receiver. By analyzing the influence of several typical channels on pseudorange error, this research explains the causes of pseudorange layered phenomenon in the double-difference observation of zero-base line. Test results in practical channels prove the correctness of the analysis model.The model asignal quality problems and guide the optimal design of receiver channel.