Comparison Between Low Earth Orbit Satellite and Geostationary Earth Orbit Satellite in Direct-to-Phone Satellite Communication Technology

Direct-to-phone satellite communication technology is primarily applied in remote areas, emergency rescue and other scenarios where communication network coverage is significantly insufficient or a coverage dead zone. This paper mainly compares the differences between GEO and LEO satellites achieving direct-to-phone connectivity through literature analysis and comparative analysis methods. The differences include hardware technology comparisons and non-terrestrial network technology comparisons. The aim is to elucidate the differences and key technologies between GEO and LEO satellites at different orbital altitudes in achieving satellite direct-to-phone Communication, and to point out the possibilities for future integration and development of these technologies. Through the research and comparison in this paper, it is found that the GEO scheme needs a special terminal with particular chips, suitable for emergency communication but limited capacity; LEO scheme is compatible with existing mobile phones and is implemented by spaceborne base stations and large-scale antennas, which have low latency but requires dense networking. The NTN technologies effectively solve the problems of time delay and frequency shift and so on in satellite-ground fusion. In the future, the coordinated development of terminal-satellite-NTN network should be combined to realize a more efficient satellite-ground integrated communication system.