Abstract:

 A scheme of broadband mobile communication system based on multibeam antenna geostationary satellite is proposed, which has greater user capacity and better quality of services (QoS) compared with the conventional similar ones. A multiple access mode of multiple frequency time division multiple access aided by slot code division multiple access, program controlled circuit switching combined with Internet protocol switching are employed, moreover, time division multiplexing (TDM) and quasi-orthogonal TDM are employed in the downlinks, so the user capacity can be increased remarkably, the onboard equipment appears to be compacter and the QoS for Internet applications can be improved effectively. The largest number of user channels is 173 880  while the highest bit rate of the user’s downlink reaches 155 Mbps. Simulation results show that the downlinks performance can be improved for 11.65 dB for 140 beams with 26 channels 16 amplitude phase shift keying signals of each beam, compared with frequency division multiplexing transmission, which makes the equivalent aperture of a broadband user’ antenna shrink to a quarter of before and the manufacture cost reduce greatly.