GPS-IR技术用于河水面测高实验分析

Analysis of GPS-IR Water Level Altimetry Experiment on River

河流、水库、湖泊的水位监测直接为水利、水运、防洪、防涝提供具有单独使用价值的资料,对人们的生产生活具有重要的意义。GPS-IR测高技术的出现为水位监测提供了新的手段。首先介绍了基于SNR观测值的GPS-IR水面测高技术的基本原理。在西安灞河悬挑平台上使用3组不同的仪器进行GPS-IR测高实验,以水位计结果为基准分析了测高精度,并探究了频段、高度角区间、扼流圈天线对GPS-IR水面测高精度的影响。得到了最佳RMS结果为1.04cm的精度,指出目前L1频段的信噪比更适合测高反演,而GPS现代化后L2频段进行测高则是更好的选择。给出了高度角区间选取的准则,证实扼流圈天线对GPS-IR技术影响不大。实验结果表明,可利用已有的GPS变形监测站,基于GPS-IR技术选取最优的参数配置监测河流、水库、湖泊的水位变化。

The water level monitoring of rivers, reservoirs and lakes directly provides valuable materials for water conservancy, water transport and flood control, which is of great significance to people’s production and life. The GPS-IR altimetry technology provides a new means for water level monitoring. This paper introduces the basic principle of GPS-IR altimetry technology based on SNR observations. GPS-IR altimetry experiments are carried out on the Xi’an Bahe cantilever platform using three different instruments. The precision analysis of GPS-IR altimetry is carried out based on the water level gauge. This paper studies the impact of frequency, elevation angle and choke coil antenna on GPS-IR altimetry precision. The best RMS result is 1.04 cm. It is pointed out that at present, the signal-to-noise ratio of the L1 band is more suitable for altimetry. It is a better choice to measure the height of the L2 band after GPS modernization. The criterion for selecting the elevation angle is given. It is confirmed that the choke antenna does not affect the GPS-IR technology. The experimental results show that the existing GPS deformation monitoring station can be used to select the optimal parameter configuration based on GPS-IR technology to monitor the water level changes of rivers, reservoirs and lakes.