An improvement of reservation code multiple access for integrated voice/data spread-spectrum system

For local wireless communication, the reservation code multiple access (RCMA) protocol has been proposed as a promising MAC protocol. However, heavy collisions make more packet dropping in the heavy load condition in RCMA because RCMA uses the data packet itself to make a channel reservation, which is inefficient in that each unsuccessful reservation wastes one code. A new method, improved reservation code multiple access (IRCMA) based on the dynamic reservation spread code for an integrated voice and data spread-spectrum system is proposed in this paper. IRCMA splits the slot into several minislots if any code is an available one. This scatters users to contend available codes at different times. It reduces user access collisions and improves system performance according to computer simulation results.