A novel multiple access control (MAC) protocol——User-dependent Perfect-scheduling Multiple Access (UPMA) protocol

which supports joint transmission of voice and data packets

is proposed.By this MAC protocol

the bandwidth can be allocated dynamically to the uplink and downlink traffic according to their respective service requirements.UPMA protocol endows different priority levels to different types of traffic

and can perfectly schedule the transmission of mobile terminals (MTs) by means of polling.Meanwhile

a unique frame structure is designed to guarantee that the voice traffic is always transmitted prior to the data traffic.Furthermore

an effective collision resolution algorithm is proposed to guarantee rapid channel access for activated MTs.Finally

performance of UPMA protocol is evaluated by simulation and compared with that of MPRMA protocol.Simulation results show that UPMA protocol has better performance.