Doppler Shift Characterization for Non-GEO Satellite Channels

An analysis model based on the earth centered fixed coordinate frame is introduced, for achieving a quantitative analysis of Doppler shift characteristics over non-GEO satellite channels. The model is irrelative to the geographical coordinate of receiving terminals on the ground after approximative processing. The maximum Doppler shift in some typical non-GEO satellite channels are figured out. It is concluded that Doppler shift is weaker in the high elevation angle state, and is maximal in the visible elevation angle state. As a result signals should be received at the high elevation angle. In order to weaken the impact of the time-selective fading, the Doppler-time regulation as a prior knowledge can be used for estimating and compensating the Doppler shift in channels.