北斗导航系统精密单点定位在地壳运动监测中的应用分析

摘要

Based on more than two years BDS/GPS data observed by seven stations,we used precise point positioning (PPP) model of the PANDA software developed by Wuhan University,analyzed the positioning accuracy of single system and discussed the ability of BDS in crustal motion monitoring.The results showed that the BDS positioning accuracy in the horizontal direction was about 17 mm and the vertical direction was about 40 mm.The GPS positioning accuracy in the horizontal direction was better than 10 mm and the vertical direction was about 14 mm.The results of baseline statistics showed that BDS had lower ability to detect weak signals than GPS system,but it was still able to accurately reflect the characteristics of baseline length and rate between two sites.Comparing the velocity fields obtained from BDS and GPS,the results showed that the difference of the two sets of velocity field in horizontal directions was 1～2 mm/a,and there was no systematic difference.Although BDS PPP accuracy was lower than GPS,but it could still be used to monitor the crustal motion of the large deformation area.%主要基于7个台站观测到的BDS/GPS双模连续观测数据,时间跨度在2a以上,利用武汉大学自主研发的PANDA软件的精密单点定位模式,对比分析了BDS/GPS双模观测数据的单系统定位精度,并探讨了BDS在地壳运动监测中的能力.通过对这些观测数据的解算及分析,结果表明,BDS在水平向的定位精度约为17 mm,垂向定位精度约为40 mm;GPS在水平向的定位精度要优于10 mm,垂向定位精度约为14 mm.基线统计结果显示,BDS检测弱信号的能力要低于GPS,但仍能够准确反映站点间基线长度和变化率特征.对比分析BDS和GPS得到的速度场,结果显示,两套速度场在水平向之间差值约为1～2 mm/a,且不存在系统性的差异.总体来看,虽然目前BDS精密单点定位精度要低于GPS,但是BDS目前仍可以用于监测形变量较大的地区地壳运动.