A demand-assignment access control for multi-code DS-CDMA wireless packet (ATM) networks

Abstract

In a wireless packet (e.g., ATM) network that supports an integrated mix of multimedia traffic, a large variety of mobiles with different service rates will need to be accommodated efficiently in a bandwidth-on-demand fair-sharing manner. We propose and study multi-code CDMA (MC-CDMA) with distributed-queueing request update multiple access (DQRUMA) for multi-rate wireless packet networks. The network incorporates MC-CDMA (a flexible multiplexing scheme for providing multi-rate packet transmissions) and DQRUMA (an efficient demand-assignment multiple access protocol for wireless access and scheduling) to form a unified bandwidth-on-demand fair-sharing platform for multi-rate wireless services. A slot-by-slot packet transmit scheduling policy provides the possibility of slot-by-slot allocation of pseudo-noise (PN) codes (primary codes) and optimal power levels to the mobiles involved in packet transmissions. Also, a maximum capacity power allocation (MCPA) criterion is derived to exploit the subcode concatenation property of the MC-CDMA transmission. Simulation results show that the system provides close to ideal-access performance for multi-rate mobiles, both with homogeneous traffic characteristics and with a mix of heterogeneous traffic characteristics.