Delay Optimal Power Aware Opportunistic Scheduling with Mutual Information Accumulation

TL;DR

This paper develops an online power and delay optimization algorithm for wireless links using rateless codes, accounting for time-varying channels and mutual information accumulation, to minimize delay under power constraints.

Contribution

It introduces a novel frame-based stochastic optimization framework with an online algorithm for delay-power tradeoff in wireless communication with mutual information accumulation.

Findings

The proposed algorithm effectively minimizes average delay under power constraints.

The subproblem reduces to a simple integer program solvable by dynamic programming.

Lyapunov drift analysis proves the optimality of the online scheduling algorithm.

Abstract

This paper considers optimization of power and delay in a time-varying wireless link using rateless codes. The link serves a sequence of variable-length packets. Each packet is coded and transmitted over multiple slots. Channel conditions can change from slot to slot and are unknown to the transmitter. The amount of mutual information accumulated on each slot depends on the random channel realization and the power used. The goal is to minimize average service delay subject to an average power constraint. We formulate this problem as a frame-based stochastic optimization problem and solve it via an online algorithm. We show that the subproblem within each frame is a simple integer program which can be effectively solved using a dynamic program. The optimality of this online algorithm is proved using the frame-based Lyapunov drift analysis.