Performance evaluation of a generalized hybrid TDMA/CDMA protocol for wireless multimedia with QoS adaptations
As multimedia and high transmission of continuous media, such as live audio and video, with high quality services become more popular on wireless networks, the various traffic requiring different qualities of service (QoS) will co-exist. To this end, a request time division multiple access (TDMA)/code division multiple access (CDMA) protocol for supporting multimedia traffic in wireless networks, where CDMA is laid over TDMA has been proposed recently. In this paper, we wish to extend this scheme by introducing several QoS to the end-user, and present a generalized performance analysis of a request TDMA/CDMA QoS-based protocol. Quality of service factors includes customer retrial rates due to both user impatience and system timeouts. Our proposed analytical model allows us to understand how the end-to-end QoS guarantee can be obtained by analyzing the QoS requirements at every stage of the message delivery, from arrival to contention and transmission. In our studies, we have investigated several priority queuing disciplines: First In First Out, priority, and weighted fair queueing schemes, and we have investigated how customer impatience and system timeouts can affect the QoS provided by these priority scheduling schemes. Finally, we have applied the stretch-optimal algorithm in our protocol to improve further the high quality of QoS the mobile users may obtain. (c) 2004 Published by Elsevier B.V.
tdma/cdma qualities of service medium access control