Demand assignment switching for terrestrial and satellite networks

This paper presents a demand assignment switching system, to be used in terrestrial or satellite networks. Radio channel and time slot assignments are made on user demand, while the switch operations are controlled by a scheduling algorithm designed to maximize utilization of system resources and optimize performance. User requests and assignments are carried over a low-capacity control channel, while user information is transmitted over the traffic channels. The proposed system resolves both the multiple access and the switching problems and allows a direct connection between the end users. The system also provides integration of voice and data traffic in both the access link and the switching equipment. The "movable boundary" approach is used to achieve dynamic sharing of the channel capacity between the voice calls and the data packets. Performance results presented for the case of optimum scheduling, indicate that data packets may be routed via the exchange node with limited delays, even with heavy load of voice calls. Also we have proposed scheduling algorithms that may be used in implementing this system.