北斗三频中长基线差分定位性能研究

北斗卫星系统(BDS)能全星座播发三频信号,可通过线性组合构成不同虚拟观测量,有利于模糊度解算等,文中采用北斗三频中长基线实测数据进行差分定位,首先使用宽巷模糊度和电离层无关组合进行B3频段窄巷模糊度解算,在此基础上提出利用相邻历元B3频段窄巷模糊度构建卡尔曼滤波新息向量,通过新息向量内积RMS值很容易分析出窄巷模糊度的误差对滤波性能的影响,并结合滤波发散条件进行相关卫星历元挑选,实验最终得到中长基线厘米级定位精度并有效缩短首次收敛时间和提高固定率,对促进北斗高精度定位有着现实意义。 

Middle-Lon- Range Differential Positioning Using Triple Frequency BeiDou Satellite System

Based on the unique advantages of Beidou triple frequency, we use the real measured data to study the performance of differential positioning in middle long baseline and conduct the resolution of triple ambiguity with step wise method, and resolve the B3 narrow ambiguity with the aid of wide lane ambiguity and ionospheric free combination. Then using the observation epoch selecting strategy the paper presents that combining the construction of the kalman filter innovation vector using the B3 narrow lane ambiguity in adjoin epoch with the filter divergence condition, it is easy to analyze the impact of narrow lane ambiguity error on the filter performance using the RMS of inner product of kalman filter innovation vector. Finally, we get the centimeter level differential positioning accuracy in middle long baseline and shorten the time to first fixed solution effectively and improve the fix rate that has a practical significance on promoting BeiDou high precision positioning.