Abstract: Doppler-shift correction information broadcast in a satellite mobile telephone system is produced on the assumption that mobile stations (4a, 4b) are stationary or moving slowly. Consequently, a mobile station (4a, 4b) moving at high-speed cannot correct properly for Doppler shift. In order to solve this problem, provision is made for the mobile station (4a, 4b) to know its own position and velocity, as well as that of a satellite (3a, 3b), so that it can tune its transmitter to mimic, from the perspective of the satellite (3a, 3b), a stationary or slowly moving mobile station (4a, 4b).