多卫星组合的GPS-MR土壤湿度反演

单天中卫星低高度角状态持续时间较短，导致基于单颗GPS卫星多路径信噪比SNR的土壤湿度反演时间分辨率较低。为保证土壤湿度反演结果的可靠性和准确性，同时改善土壤湿度反演的时间分辨率，顾及信噪比有效高度角区间，提出一种基于多GPS卫星组合的GPS-MR高时间分辨率土壤湿度反演方法。实验结果表明，多卫星延迟相位组合能较好地表征土壤湿度变化趋势，二者相关系数优于0.92；土壤湿度反演时间分辨率由1 d提升为2 h。

Retrieval of Soil Moisture by Using GPS-MR Based on Combined Multi-Satellite

The duration of satellite low elevation angle is shorter within one day, using the same satellite’s multipath SNR to detect soil moisture results in lower temporal resolutions. In order to ensure the reliability and accuracy of soil moisture inversion results and improve their temporal resolution, in this paper, considering the approximate range of effective altitude angles, we propose a high time resolution soil moisture inversion method based on multiple GPS satellite combinations for GPS-MR. The results show that the delayed phase combination can better characterize the change trend of soil moisture. Furthermore, the correlation coefficient between delayed phase combination and soil moisture is better than 0.92. In addition, the time resolution of multi-satellite combination improves greatly, from 1 day to 2 hours.