一种GPS移动基准站精密相对定位新算法

中文摘要: 针对GPS载波相位差分定位中差分基准站不能移动的问题，提出了一种GPS移动基准站精密相对定位的方法。该算法首先基于MW组合构造几何关测量值，然后对几何关测量值进行滑动平均滤波消除随机噪声影响，在移动站进入移动基准站数据链覆盖范围时进行站间和星间双差处理获得宽巷整周模糊度，并结合载波相位的双差几何相关模型建立Kalman滤波观测方程，将多路径误差建模为1阶Gauss Markov随机过程，作为状态参数纳入状态方程，增广状态向量，同时扩增观测方程，从而滤波获得 L 1/ L 2模糊度浮点解的精确估计，最后采用LAMBDA算法搜索固定模糊度的整数解。通过静态和车载动态实测试验验证了新算法的正确性和适用性。
Abstract:Aiming at the issue of immobility of differential reference station in GPS carrier phase differential positioning,an algorithm of GPS precise relative positioning for moving base station was proposed.Firstly,geometry free measurements were structured based on Melbourne-Wubbena combination,which were then filtered by moving average filter.The double difference processing was adopted to further eliminate common error when dynamic user comes into the data link coverage of moving base station,and then the wide lane ambiguities were obtained.At this time,Kalman filter observation equation was established in combination with carrier phase double difference geometry based model.Then multipath error was modeled as first order Gauss-Markov random process and brought into state equation as augmented state parameters,thereby accurate estimate of float solution of L 1/ L 2 ambiguity can be obtained.Lastly,the LAMBDA method was used to search the fixed ambiguity.Experiment results showed that centimeter level accuracy of relative positioning is obtained, which verifies the validity and applicability of the method.