双频去相关单历元动态解算整周模糊度研究

Research on Ambiguity Dynamic Resolution Using Dual Frequency Single-epoch Data

针对GPS实时动态精密相对定位应用背景,提出一种整周模糊度实时求解方法。采用宽巷组合载波相位双差、伪距双差观测信息建立观测模型;对浮点模糊度协方差阵进行一次Cholesky分解,构造了浮点转换矩阵,使浮点模糊度完全去相关;推导确定整周模糊度的搜索空间;利用最小残差平方和搜索准则,确定单历元整周模糊度,并用OVT检验方法,对不同历元得到的整周模糊度进行一致性检验。结果表明,观测量误差均方差取值对整周模糊度搜索空间和成功率有较大影响,附加OVT检验的双频去相关单历元动态解算整周模糊度方法正确可行。

Aecording to the application of GPS differential precise navigation, an ambiguity resolution algorithm is presented. The mathematical model is set up using observations of wide lane double differential carrier phase and double differential pseudorange. In order to make float ambiguity ancorrelated completely, float transformation matrix is constructed by Cholesky decomposition and the integer ambiguity search space is deduced. The criterion of least square residual is used to obtain single-epoch integer ambiguity, OVT （over-the-time） method is applied to verify the consistency of integer ambiguity at different epochs. Experimental results indicate that the mean square deviation of observations has great effect on integer ambiguity＇ s search space and success rate, and the integer ambiguity can be determined correctly and reliably by OVT testing.