Abstract：Global Navigation Satellite System Reflectometry (GNSS-R) is an effective Earth observation method that uses the analysis of navigation satellite reflection signals to invert surface parameters. Historical research has shown that traditional GNSS-R systems mainly adopt a single polarization configuration (righthanded circularly polarized (RHCP) transmission and left-handed circularly polarized (LHCP) reception, hereinafter referred to as LR polarization), and the study of scattering characteristics of other polarization combinations is relatively weak. With the advancement of technology, the scheme of using RHCP antenna to receive surface reflection signals has gradually gained attention. Meanwhile, the traditional Delay Doppler Map (DDM) processing mode of GNSS-R has low efficiency in utilizing scattering features under different observation geometries. In this context, the development of GNSS based Synthetic Aperture Radar (GNSS-SAR) technology that can effectively receive surface scattering signals across geometric configurations has become a promising research direction. This study focuses on the remote sensing exploration of the fusion technology of reduced polarization GNSS-R and synthetic aperture radar (GNSS ReSAR: GNSS Reflectometry and Synthetic Aperture Radar). Based on the dual polarization (LR and RR (RHCP launch and RHCP reception) data obtained from the Spanish airborne GLORI experiment, soil moisture inversion research was carried out, and the dual polarization GNSS-R data from the Chinese Tianmu (TM) commercial satellite was synchronously used for comparative verification. Both experiments consistently showed that the reflectance of RR polarization was about 10 dB lower than that of LR polarization, but the accuracy of soil moisture inversion based on the two polarizations was comparable. Due to the limited ability to obtain simplified polarization data, this study uses the LAGRS (Land Surface GNSS Reflection Simulator) model constructed based on radiative transfer theory to analyze other scattering characteristics of simplified polarization. By systematically analyzing the scattering mechanism and development trend of GNSS ReSAR mode, it provides theoretical reference for the evolution of the new generation GNSS-R technology to a certain extent.