A system and method for the efficient use of satellite radio modems and
satellite bandwidth is disclosed. In the system and method, a satellite
radio modem is used for PRACH requests, each PRACH request occupying
31.25 kHz in a packet data transfer channel. The packet data transfer
channels can be either 125.0 kHz or 156.25 kHz. Therefore, four PRACH
requests can be transmitted in any one packet data transfer channel. The
packet data transfer channels are broken into eight time slots, and one
time slot in each channel (either the odd frame or even frame) is
dedicated to a PRACH request. A satellite radio modem for PDCH transfers
is dedicated for each channel. The satellite radio modem assigned to
receive the four PRACH requests is timeshared over 16 channels, thereby
reducing the amount of satellite radio modems that would otherwise have
been needed, had the PRACH request transmissions utilized a dedicated
modem for each PRACH request, for each channel.