Abstract: With improvement of Beidou navigation satellite system, multi frequency and multi- mode GNSS, especially the BDS/GPS combined positioning, has become a hot research and application subject. The introduction of Beidou satellite greatly increases the availability and reliability of the satellite signal, and provides an effective way to solve the problem of number of GNSS deformation monitoring satellites and enhances the signal quality for hydropower dam in mountainous valley of southwest China. In this paper, the monitoring accuracy of BDS/GPS combined positioning for deformation monitoring in the complex environment of Guandi hydropower station is introduced. The results show that the internal and external accord accuracy meet the requirements of precise deformation monitoring for the dam in mountainous valley.

Key words: alpine gorge, dam deformation monitoring, BDS/GPS combined positioning, accuracy

摘要： 随着我国北斗导航卫星系统逐步建立完善，多频多模GNSS特别是北斗/GPS组合定位已成为行业研究和应用热点。北斗卫星的引入，大大增加了卫星信号的可用性和可靠性，为解决西南深山峡谷地区水电站大坝GNSS变形监测卫星数量和信号质量问题提供了有效办法。在官地水电站大坝坝顶进行了北斗/GPS组合定位变形监测精度测试。结果表明，在高山峡谷典型环境条件下，内、外符合精度均满足大坝精密形变监测要求。

关键词: 高山峡谷, 大坝变形监测, 北斗/GPS组合定位, 精度