Abstract: A satellite communications scheme for enhancing the communications system with existing satellites is disclosed. The existing satellites include a transponder having a phase locked loop phase demodulator at the front end thereof. The present invention discloses a technique wherein the phase demodulator is locked by transmitting a relatively high-power carrier from the ground to the satellite transponder. Once the demodulator has been locked, remote ground terminals operating at much lower power levels can access the satellite transponder by transmitting at carrier frequencies spaced apart from the primary high-power carrier. These are down-converted by the transponder phase demodulator and then typically amplitude and frequency limited before being remodulated and retransmitted.