北斗站间单差载波相位差分定位方法

Inter-station differenced carrier phase method for BDS RTK positioning

针对传统基于站间-星间双差载波相位差分存在放大观测量随机误差,使得卫星间存在耦合,导致参考星变换时产生整周跳跃的问题,提出一种基于站间单差模型的精密定位算法,通过站间单差消除大气延迟、卫星端等偏差,保持了卫星间观测量的独立性,并结合双钟差模型以保持载波相位的整周特性。通过北斗实测车载实验进行了验证,测试结果表明,基于改进的单差模型定位精度达到厘米级,模糊度固定率达到90%以上。

The traditional double difference (DD)model not only enlarges observational noise,but also leads to correlation of inter-observations.Moreover,the change of reference satellite will yield the phenomenon of "integer jumps".A model of carrier phase single difference (SD)for achieving absolute precise positioning is proposed.The proposed method not only implements SD to mitigate satellite and atmospheric errors to maintain the independence of observations,but also reserves the integer nature of carrier-phase.To eliminate the effect of receiver errors,the double clock model is adopted.The BDS data from the vehicle experiment is collected to test the performance of the proposed method.The results show that the proposed method can achieve the decimeter level of positioning accuracy and over 90% ambiguity resolution success rate.