BDS/INS紧组合三频动对动模糊度解算方法

针对伪距观测噪声较大导致动对动条件下三频整周模糊度解法(Three Carrier Ambiguity Resolution, TCAR)模糊度解算不可靠的问题,提出了一种BDS/INS紧组合三频动对动整周模糊度解算方法。通过紧组合系统输出的高精度位置坐标,估算出双差几何距离值,并用其分别代替无几何和几何模式下的双差伪距观测值,显著降低了伪距双差观测噪声水平,有效提高了三频整周模糊度解算成功率。仿真实验结果表明,BDS/INS紧组合输出的高精度位置坐标使得伪距观测精度提高了60%以上,在短基线条件下,当伪距观测噪声达到2 m时,无几何模式下的TCAR算法模糊度解算成功率为0.73%,几何模式下的TCAR算法模糊度解算成功率为31.25%,而BDS/INS紧组合的TCAR算法在两种模式下的模糊度解算成功率达到99%以上,并且获得了厘米级的相对定位精度。

Triple-frequency kinematic-to-kinematic ambiguity resolution with BDS/INS tightly-coupled integration

Aiming at the problem that when pseudorange observation noise was high, and the ambiguity calculation of TCAR(three carrier ambiguity resolution) method was unreliable in the condition of kinematic-to-kinematic, a triple-frequency kinematic-to-kinematic ambiguity resolution with BDS/INS tightly-coupled integration was proposed. Replacing the double-difference pseudorange observations in GF(geometry-free) and GB(geometry-based) patterns with the double-difference geometry distances estimated by the tightly-coupled integration system, the method obviously decreased the noise level of the pseudorange double-difference observations and improved the success rate of triple-frequency ambiguity calculation. Simulation results show that, the high-precision position output of BDS/INS tightly-coupled integration improved the accuracy of pseudorange observations by more than 60%. In short-baseline condition, when the pseudorange observation noise is 2 m, the success rate of triple-frequency integer ambiguity calculation by GF-TCAR is 0.73% while 31.25% by GB-TCAR. However, the integer ambiguity calculation success rate by the new TCAR method is beyond 99%. And this new solution can achieve centimeter-level kinematic-to-kinematic relative positioning.