基于相关功率修正的地基GNSS-R土壤湿度反演

In soil moisture observation using Global Navigation Satellite System Reflectometry (GNSS-R) technique, actual antennas' directionalities will bring about the biases in the correlation power measurements of the direct and reflected GNSS signals. For eliminating the cosine-like oscillatory bias of the correlation power caused by antenna directionality in ground-based scenario, this paper proposes a correlation power correction method based on the polynomial fitting. In order to verify the validity of this method, the ground-based GNSS-R soil moisture observation experiment is carried out. The experimental results show that the correlation power correction using polynomial fitting can remove the cosine-like oscillation of the correlation power waveform, and then improve the efficiency of measurement data and the accuracy of retrieval results.