We study a problem of scheduling real-time traffic with hard delay constraints in an unreliable wireless channel. Packets arrive at a constant rate to the network and have to be delivered within a fixed number of slots in a fading wireless channel. For an infrastructure mode of traffic with a centralized scheduler, we are interested in the long time average throughput achievable for the real time traffic. In [1], the authors have stud- ied the feasible throughput vectors by identifying the necessary and sufficient conditions using work load characterization. In our work, we provide a characterization of the feasible throughput vectors using the notion of the rate region. We then discuss an extension to the network model studied in [1] by allowing multiple access during contention and propose an enhancement to the rate region of the wireless network. We characterize the feasible throughput vectors with the multiple access technique and study throughput optimal and utility maximizing strategies for the network scenario. Using simulations, we evaluate the performance of the proposed strategy and discuss its advantages.
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