Joint channel and queue aware scheduling for wireless links with multiple fading states

In this work, we address the delay optimal scheduling problem for wireless transmission with fixed modulation over multi-state fading channels. We propose a stochastic scheduling policy which schedules the source to transmit with probability jointly based on the buffer and channel states, with an average power constraint at the transmitter. Our objective is to derive the optimal transmission probabilities such that the average queueing delay is minimized subject to the power constraint. Using Markov chain modeling, we formulate a power-constrained delay minimization problem, and then transform it into a Linear Programming one. By analyzing its property, we can derive the optimal threshold-based scheduling policy together with the corresponding transmission probabilities. Our theoretical analysis is corroborated by simulation results.