Resource Allocation in OFDMA with Time-Varying Channel and Bursty Arrivals

This paper considers the issue of delay optimal subcarrier allocation in OFDMA wireless networks when the arrivals and channels are stochastic. Our objective is to minimize the long-term average packet delay over multiple time epochs. In previous studies, we have shown that the optimal policy is complicated and unknown. However, based on the insights learned from a simple on-off channel model, we provide heuristic policies that use different degrees of channel and queue state information. More importantly, these examples show how the significance of queue vs. channel state information varies with the traffic load. This is of extreme practical interest when one considers the overhead associated with channel estimation and feedback.