Lunar surface radiation brightness temperature simulation for FY-4 lunar calibration

The Feng Yun-4 satellite (FY-4) is a new generation of meteorological satellite developed independently by China, which will greatly improve the capability of meteorological monitoring and forecasting. Millimeter and Submillimeter Sounding/Imager (MMSI) is an important payload it carries. To carry out the lunar calibration of FY-4, the inversion of the main metallic substance content of the lunar surface based on the data from the U.S. Clementine satellite is used to obtain the dielectric constant distribution. Then the lunar surface brightness temperature (TB) radiation model is established by combining the basic lunar regolith parameters. The accuracy and reliability of the method are verified using Chang'e-2(CE-2) MRM data. Finally, the radiation TB distribution of FY-4 MMSI terahertz band in the lunar equatorial region is simulated, which can provide experience for future geostationary satellite satellite-based sounder lunar calibration work.