基于GNSS双天线测姿的水位监测方法

Water level monitoring method based on GNSS dual antenna attitude measurement

水位监测是雨水情监测预报“第三道防线”中的重要内容,精确、实时的水位监测在洪涝灾害防御中至关重要。水位计是最常见的水位测量工具,其能有效测量特定区域的相对水位信息,但往往存在成本较高、空间分辨率较低等问题。由于全球导航卫星系统反射测量(Global Navigation Satellite System-Reflectometry,GNSS-R)技术具有低成本、高时空分辨率的优势,因此提出了一种基于全球导航卫星系统(Global Navigation Satellite System,GNSS)双天线测姿的实时水位监测新方法。该方法通过双差观测组合,消除了卫星钟差、接收机钟差、电离层延迟、对流层延迟等误差。为了验证该方法的稳定性和可靠性,在北京市东沙河站开展现场试验。2023年6月5日至7月10日的实验结果表明该方法可以实现1 Hz的水位监测,与现场水尺数据相比,均方根误差为2.88 cm。

Water level monitoring is an important part of the"third line of defense"in rain-water monitoring and forecasting,and accurate and real-time water level monitoring is very important in flood disasters.The most prevalent method for measuring water level is the use of water level gauges,which can be costly and have limited spatial resolution.In recent years,Global Navigation Satellite System-Reflectometry(GNSS-R)technology has emerged as a promising approach for water level monitoring due to its low cost and high spatiotemporal resolution.This paper introduces a novel real-time water level monitoring method based on GNSS dual-antenna attitude measurement and develop a model to invert water level based on baseline vector.This method uses double-difference observations to eliminate errors caused by various factors,such as satellite and receiver clock bias,ionospheric and tropospheric delay.In order to verify the stability and reliability of this method,field tests were carried out at Dongshahe Station in Beijing.Experimental results from June 5 to July 10,2023 show that the method can achieve 1 Hz water level monitoring with a root mean square error(RMSE)of 2.88 cm compared to on-site water gauge data.