双频GPS接收机单差硬件延迟分析

Analysis of GPS Dual-frequency Single Differenced Receiver Hardware Delay

采用超短基线伪距单差模型分析了多种GPS接收机的硬件延迟,并对硬件延迟进行线性回归,建立了硬件延迟的线性模型。结果表明,接收机的硬件延迟总体稳定,某些接收机硬件延迟与时间不存在系统性相关,即使存在系统性相关,也足以用线性模型来精确表达。同时提出了基于双频观测值定位的单钟差模型,并用实际算例比较了单钟差模型和双钟差模型的解算精度。结果表明,当两个频率跟踪相同的卫星,且观测精度相等时,两种模型的基线解等价,且采用单钟差模型可有效地提高参数解的精度和稳定性。

The hardware delays of several dual-frequency GPS receivers are investigated based on single differenced model in the ultra-short baselines, and regressed by a linear regression model. Additionally, the single clock-error parameter model for dual-frequency observations is proposed. Experimental result shows that the hardware delays for all receivers are rather stable in time domains, and some of which are even free of time correlation, and the others with significant time correlation can be regressed with a linear model very well. It is also shown that the position solutions of two models are exactly equivalent with the assumption of tracking the same satellites and the equal accuracies for all observation at two frequencies. The accuracy of estimator can be significantly improved by using the single clock-error pa- rameter model.