Modeling and eliminating of multipath and distance-dependent errors on virtual reference stations
Jingxiang Gao · Journal of China University of Mining and Technology · 2011
Firstly,the network differential positioning technology based on virtual reference station(VRS) was discussed.Then multipath errors of widelane combination which restricted the real-time ambiguity resolution were modeled and eliminated and the correlation coefficient of the multipath errors of two consecutive day was calculated and analyzed.Meanwhile,the dispersive and non-dispersive errors were modeled and a moving average model was applied to obtain smooth non-dispersive correction.The stochastic model based on signal strength was employed to resolve the integer ambiguity of L1 carrier-phase measurements and baseline after the dispersive and non-dispersive errors was eliminated.A test was conducted using five stations of the national geodetic survey-continuously operating reference stations(NGS-CORS).The results confirm that the efficiency and the reliability of ambiguity resolution of widelane combination are remarkably improved when the dispersive and non-dispersive errors are eliminated.The positioning accuracy can be improved about 30%-45% and the position biases are reduced obviously.