Circuit and packet integrated switching in a satellite communication channel

The paper describes a switching scheme for satellite communication systems employing both lightly loaded (bursty) and heavily loaded terminals. In the proposed scheme, the frame is partitioned into two types of subframes for servicing the two types of terminals. The subframe for heavily loaded terminals consists of the reservation channel and the message channel. The subframe for lightly loaded terminals employs a slotted ALOHA scheme for the transmission of packets. The heavily loaded terminals make reservation through reservation-channel using reservation packet, and send messages by using time slots of the message-channel. Analysis is performed to derive the mean packet transmission delay for the lightly loaded terminals and the mean message transmission delay for the heavily loaded terminals. It is shown that if one type of delay is controlled then there exists an optimum frame length that minimizes the other type of delay. It is also shown that the transmission delay of the proposed scheme is shorter than those of the conventional TDMA and the slotted ALOHA schemes.