北斗/GPS融合静态相对定位用于高精度地面沉降监测的试验与结果分析

EXPERIMENT AND RESULTS OF HIGH PRECISION LAND SUBSIDENCE MONITORING USING FUSED BDS / GPS DATA AND STATIC RELATIVE POSITIONING

我国的北斗卫星导航系统(Bei Dou Navigation Satellite System,缩写为BDS)已于2012年12月27日正式对亚太大部分地区提供连续无源定位、导航和授时服务。为了探讨BDS/GPS融合观测数据用于高精度地面沉降监测的效果和精度情况,利用5台兼容BDS和GPS系统信号的GNSS接收机,对西安市地面沉降GPS监测网中的9个监测点进行了复测。通过对连续观测10h以上4个时段观测数据的处理和分析,结果表明,相对于单独采用GPS观测数据进行基线解算而言,融合了BDS和GPS观测数据基线结果的内符合精度大大提高,水平方向的平均中误差从±5mm改善至±3mm,垂直方向的平均中误差从±17mm改善至±12mm;同时,监测结果的外符合精度也大大增强,X、Y、Z方向的平均中误差分别从±6mm、±15mm、±10mm改善至±1.5mm、±8mm、±5mm。这说明融合了BDS观测数据的BDS/GPS静态相对定位可以明显提高高精度地面沉降监测结果的内外符合精度。

Beidou Navigation Satellite System (BDS)of China has formally provided the service of continuous passive positioning,navigation and timing for most area of Asia-Pacific since December 27,2012.In order to inquire the effect and precision of the high precision land subsidence monitoring using fused BDS /GPS observation data,five GNSS receivers which can synchronous receive the signal of BDS and GPS are used to monitor the land subsidence of Xi′an repeatedly at 9 points of the original GPS network.Then 4 session observation data which continue over 10 hours are processed and analyzed.The results indicate that the internal accordant accuracy of baseline which merges the BDS and GPS data is improved greatly relative to the accuracy of baseline solved using the single GPS observation data.The average error of horizontal direction is improved from ±5mm to ±3mm,and the average error of vertical direction is improved from ±17mm to ±12mm.In the mean time,the external accordant accuracy of monitor results is also enhanced greatly.The average error of X,Y,Z direction is improved from ±6mm, ±15mm and ±10mm to±1.5mm,±8mm and ±5mm respectively.Those phenomena indicate that the internal and external accordant accuracy of results for high precision land subsidence monitoring can be improved obviously using the fused BDS /GPS observation data.