动态PPP定位中周跳自动探测与处理策略

Cycle-slip automatic detection and processing strategy for dynamic PPP

周跳的自动探测与有效处理是动态PPP定位中关键和棘手的问题．本文提出利用L1、L2、L4、L5历元间差分，并联合doppler积分综合探测与定位周跳．对准确判定发生周跳的卫星，不进行周跳的固定和修复，而是将其作为新升起的卫星重新估计模糊度．这一处理策略避免了周跳修复不准对整个定位精度的影响，当保证不少于4颗卫星连续跟踪时，PPP动态定位的精度是稳定的，实验结果表明：在相对比较恶劣的动态环境下，动态PPP定位精度可以达到0．1～0．2m水平．

Cycle-slip Automatic detection and accurate estimation is a key but difficult problem in dynamic PPP. A new method for detecting and locating the cycle-slip is presented by utilizing the L1, L2, L4, L5 and Doppler observations. If the cycle slip is detected accurately, the corresponding satellite is treated as a new rising satellite, so its ambiguities must be re-initialized. The advantage of the processing strategy is that dynamic PPP precision is stable if the number of the satellites is no less than four, because integer slip cycles needn＇t be calculated and repaired which is very difficult in dynamic PPP. The shipborne experimental results show that dynamic PPP precision reaches 0. 1-0.2 meters by taking the double difference baseline length as a reference on the heavy dynamic environment condition.