利用无几何模型求解GPS三频模糊度的成功率分析  

ANALYSIS OF SUCESS RATE FOR GPS THREE-CARRIER AMBIGUITY RESOLUTION USING GEOMETRY FREE MODEL

作　　者：常志巧[1] 刘利[1] 郭睿[1] 刘雁雨[1] 

机构地区：[1]北京环球信息应用开发中心,北京100094

出　　处：《大地测量与地球动力学》2011年第4期119-122,131,共5页Journal of Geodesy and Geodynamics

基　　金：武汉大学地球空间环境与大地测量教育部重点实验室测绘基础研究基金(10-014)

摘　　要：利用无几何模型求解GPS模糊度实数解是不以基线分量为未知数的线性模型,码观测量几乎直接用于确定模糊度,即使在较短的观测时间内,也不会出现设计矩阵复共线性,对模糊度求解具有明显优势。利用Krone-cker乘积导出了利用无几何模型求解三频模糊度及其协方差矩阵的表达式,分析得到该协方差矩阵只与伪距噪声和相位噪声之间的结构以及采用的历元数相关,与接收机和卫星之间的几何构形无关;整数变换Z矩阵只与伪距噪声和相位噪声之间的结构相关的有益结论。最后利用无几何模型分别计算了单频、双频、三频模糊度求解的成功率,得出对于双频和三频只需少数历元即可成功固定模糊度,特别对于三频观测,甚至单历元即可成功固定模糊度。Geometry free model for resolving GPS ambiguity is a linear model which does not take baseline components as unknown parameters. For the Geometry free model, the code observation is almost used in ambiguity resolution directly , and although the observation time span is very short, the design matrix will not have character istics of muhicollinearity, so that the geometry free model is very useful in ambiguity resolution. In this paper, the expressions for triple frequency float ambiguities and covariance matrix for the geometry free model have been de- duced by use of the Kronecker product. The phenomena that the expression of covariance matrix is independent from the geometry between the receiver and satellites but only relates with code and phase noise and number of ep- ochs , and the Z-transformation martrix Z is independent of the geometry between the receiver and satellites and number of epochs but only relates with code and phase noise is discovered by analysing the expression. Further more, the success rate of ambiguity resolution for single frequency, dual frequency and triple frequency is computed respectively. At last, the conclusions that only a few epochs need fixing ambiguities for dual frequency and triple frequency, and especially for triple frequency only one epoch needs fixing ambiguities are drawn.

关 键 词：GPS 无几何模型 三频模糊度求解 模糊度降相关 成功率 

分 类 号：P228[天文地球—大地测量学与测量工程]