天津市GNSS地面沉降监测数据解算改进策略

Improved strategies of GNSS data processing for monitoring land subsidence in Tianjin

为了进一步提高全球卫星导航系统(GNSS)在地面沉降监测中的精度,提出一种GNSS地面沉降监测数据解算改进策略:选择GNSS连续站作为沉降监测基准;采用最优的计算模型;改进平差方法。以天津市2007—2008年数据为例验证,结果表明,GNSS高程时间序列残差的均方根可以减小27%~44%;地面沉降年度速率误差平均减小35%左右;高程时间序列中的年度内地面沉降变化趋势更加明显,GNSS连续站表现出线性沉降或周期性波动式沉降。提出的改进策略可以有效解决地面沉降监测中的基准问题,并提高地面沉降的监测精度。

In order to further improve the accuracy of land subsidence monitoring with global navigation satellite system(GNSS),the paper proposed the improved strategies of GNSS data processing for monitoring land subsidence:GNSS continuously operating stations were selected as the monitoring datum of land subsidence;the optimal calculation models were adopted;the adjustment method was developed.Taking GNSS data from 2007 to 2008 in Tianjin city as an example,results showed that the strategies could reduce the root mean square of residual of GNSS height time series by 27%~44%,and decrease the the annual rate error of land subsidence by about 35%on average;moreover,it could make the yearly variation trend of land subsidence in height time series be more obvious,with a linear subsidence or periodic fluctuating subsidence indicated by GNSS continuously operating stations.The proposed method would help solve the datum problem of land subsidence monitoring effectively and improve the monitoring precision of land subsidence.