應用PPK在不同遮蔽情況下GPS/GLONASS/BDS成功率與精度之研究

本研究利用Novatel ProPak6 GPS/GLONASS/BDS整合式接收儀之衛星追蹤站進行原始資料蒐集，並使用NovAtel公司之GrafNav 8.60軟體進行態後處理技術（post processed kinematic, PPK)分析，比較GPS單一系統與GPS/GLONASS雙系統及GPS/GLONASS/BDS多系統組合差分定位在遮蔽區定位精度之研究。而遮蔽狀況皆選擇在路寬20米兩側皆為三樓投天厝之路旁設站，結果顯示，2公里短基線在遮蔽情況下， GPS/GOLNASS雙系統對於單系統解算成功率無明顯改善，但GPS+GLONASS+BDS三系統解算成功率可提升35.9%，內部精度平面約提升12.4%，但高程精度下降44.2%，外部精度平面約提升5%，高程約下降 40.1%。6公里基線在遮蔽情況下改善幅度與2公里基線差異不大。12公里基線在遮蔽情況下改善幅度與6公里基線差異不大。21公里基線遮蔽情況下， GPS/GLONASS雙系統對於單系統無明顯改善，但GPS+GLONASS+BDS三系統解算成功率約下降38.7%，內部精度平面約下降56.1%，高程精度約下降38.6%，外部精度平面約下降58.8%，高程約下降36.9%。

關鍵字

PPK ； RTK ； GPS ； BDS ； GLONASS

並列摘要

In this study, the original data were collected using the satellite tracking station with Novatel ProPak6 GPS / GLONASS / BDS integrated receiver, GrafNav 8.60 software produced by Novatel was used to carry out post processing kinematic (PPK) analysis and the comparison of differential positioning between GPS single – system, GPS / GLONASS dual system and GPS / GLONASS / BDS multi – system were performed for investigation of positioning accuracy in the shielding area. To determine the effect of shielding condition to the system, the test stations are set up on the roadside of 20 meters width road with three-story house on both sides. The results show that under shielding condition, the GPS / GOLNASS dual system has no significant improvement in the success solving rate compared to the single system in the case of 2 km short baseline; however, the success solving rate of GPS + GLONASS + BDS system improved 35.9%; the precision plane increased 12.4%, but the elevation precision decreased by 44.2%; the accuracy plane increased 5% and elevation accuracy decreased 40.1%. In shielding condition, the improvement is insignificant compared 6 km baseline case to 2 kilometers case. In shielding condition, the improvement is insignificant compared 12 km baseline case to 6 kilometers case. No significant improvement compared GPS / GLONASS dual system to single system in 21 km baseline shielding case, but the success solving rate in GPS + GLONASS + BDS tri-systems decreased 38.7%; precision plane decreased 56.1% and elevation precision decreased 38.6%; accuracy plane decreased 58.8% and elevation accuracy decreased 36.9%.