Theoretical analysis of soil freeze/thaw process on DDM waveform and multipath in order for GNSS-R/IR applications

• Main Authors: WU Xuerui, XIA Junming, BAI Weihua, ZHANG Xinggang
• Format: Article
• Language: zho
• Published: Surveying and Mapping Press 2019-08-01
• Series: Acta Geodaetica et Cartographica Sinica
• Subjects: gnss-r/ir; soil freeze/thaw process; delay doppler map; multipath; bistatic scattering full polarization
• Online Access: http://html.rhhz.net/CHXB/html/2019-8-1059.htm

In order to extend the applications GNSS-R/IR(GNSS-reflectometry/interferometric reflectometry) remote sensing technique to soil freeze/thaw process detection, soil(frozen/thawn) mixing permittivity models are employed to calculate the soil permittivity. Bistatic full-polarization coherent scattering model and random roughness surface scattering model are used to calculate the coherent and non-coherent scattering, which result in the variations of GPS multipath observables and DDM(delay Doppler map) waveforms, respectively. When the soil freeze/thaw process occurs, theoretical simulations indicate that soil freeze/thaw process induce the abrupt permittivity changes and affect the obvious variations of GNSS-R/IR signals. In this way, theoretical fundamentals for soil freeze/thaw process detections are presented.