Research on Regional ERIP Characteristics of GPS Satellites Received by the CYGNSS

Effective isotropic radiated power (EIRP) calibration is the main bottleneck limiting the accuracy of Global Navigation Satellite System Reflection (GNSS-R). It requires for comprehensive analysis on EIRP characteristics. Due to the limitations of experimental equipment and scenarios, we could not obtain enough data to conduct such a study until the global EIRP received by the Cyclone Global Navigation Satellite System (CYGNSS) has been made public. In this paper, the EIRP of GPS satellites received by CYGNSS 1 in 2019 is counted and regional EIRP characteristics are comprehensively analyzed. Firstly GPS satellites are divided into three types based on the similarity in EIRP characteristics at off-boresight and azimuth. Then the distribution features of regional mean EIRP at different latitudes and longitudes are summarized. To explore the related factors to the distribution, the special zones are focused and it is analyzed that how two possible factors which are the difference between the regional EIRP characteristic curve and the global curve and the distribution at off-boresight of EIRP affect the distribution. The consistency in twelve months and the entire year is also proved. Comprehensive analysis is conducted on the distribution of regional mean EIRP and its related factors. This work will provide more solid scientific guidance for EIRP calibration in different regions.