Research progress and prospects of GNSS-IR interpretation of surface environmental parameters
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摘要: 全球卫星导航系统(GNSS)具有全天候、近实时、高精度的特点,可持续发射L波段信号,广泛应用于定位、导航和授时(PNT). 随着GNSS研究与应用的不断深入,全球定位系统干涉反射(GNSS-IR)技术为地表参数探测提供了一种全新的手段. GNSS无线电导航信号经不同地表介质(如土壤、积雪、水面等)反射后,被反射的GNSS多路径信号承载反射面的特性信息,通过对GNSS反射信号中振幅、相位和频率等参数的分析,可有效获取地表反射面的物理参数. GNSS-IR作为当前GNSS和遥感领域的研究热点,取得了一些研究进展和成果. 本文详细介绍了GNSS-IR原理和方法及该技术在土壤湿度、植被、积雪和水位等方面的应用进展,并在此基础上,提出GNSS-IR研究中存在的问题及发展方向.
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关键词:
- 全球卫星导航系统(GNSS) /
- 多路径效应 /
- 信噪比(SNR) /
- 地表环境参数
Abstract: The Global Navigation Satellite System (GNSS) has the characteristics of all-weather, near real-time, and high accuracy, and can continuously transmit L-band signals, which are widely used for positioning, navigation, and timing (PNT). As the research and application of GNSS continue to grow, the Global Positioning System Interferometric Reflectometry (GNSS-IR) technology provides a new means of surface parameter detection. After the GNSS radio navigation signal is reflected by different surface media (such as soil, snow, water surface, etc.), the reflected GNSS multipath signals carry the characteristic information of the reflecting surface, and the physical parameters of the surface reflecting surface can be effectively obtained through the analysis of parameters such as amplitude, phase, and frequency in GNSS reflecting signals. GNSS-IR, as a current research hotspot in the field of GNSS and remote sensing, has made some research progresses and achievements. This paper introduces in detail the principle and method of GNSS-IR and the progress of the application of this technology in soil moisture, vegetation, snow and water level. Based on this, problems and development directions in GNSS-IR research are presented. -
图 5 GNSS解译土壤湿度与位移监测序列[30]
图 6 形变速率与解译土壤湿度关系[30]
图 7 相位与原位土壤湿度比较[45]
图 8 负振幅和MODIS NDVI对比结果[45]
图 9 软件主界面[62]
图 10 SC02和GTGU站点估算的海面高度变化[73]
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