The countries of the world are using various communication services in all areas of society on based satellite networks. The International Telecommunication Union has allocated two kind of satellite positions in Geo-Synchronous Orbit (GSO) space to Mongolia that are 113.6E longitude for Fixed Satellite Service-(FSS) and 74E longitude for Broadband Satellite Service- (BSS). Therefore, Mongolia is planning to launch its national satellite in 2030. Thus, we are studying many kind of science research including estimate satellite geometry parameters, rain attenuation, cloud attenuation and satellite network architecture on based national satellite that will be deployed to space segment. The purpose of this research work is to predict the estimation of rain and cloud attenuation based on the national satellite link that will be launched at space segment 113.6 E from Mongolia. First, it is defined requirements of propagation effects of satellite communication and analyze some related research work and literature. Then, it is calculated geometry parameters of geostationary satellite, the look angles of ground station antenna by using mathematical model by each regions of Mongolia. It is important to calculation rain and cloud attenuation. After that, to estimated calculation of rain and cloud attenuation by using ITU-R mathematical model by each region for Mongolia. Finally, we analyzed comparative study of calculated result of rain and cloud attenuation to show some result.

Keywords : Geometry parameter, rain attenuation, cloud attenuation, ITU-R model, Satellite frequency