Slow-Link Adaptation Algorithm for Multi-source Multi-relay Wireless Networks Using Best-Response Dynamics

Abstract

In this paper, we propose a link adaptation algorithm for slow-fading half-duplex orthogonal multiple access multiple relay channel under a centralized node scheduling approach. During the first phase, the sources transmit in turn. During the second phase, a scheduled node (relay or source) transmits incremental redundancies on its correctly decoded source messages. The proposed algorithm aims at maximizing the average spectral efficiency under individual QoS targets for a given modulation and coding scheme family. The main principle of the algorithm is to reduce the complexity, and this is achieved using Best-Response Dynamics (BRD) tools. The rates are first initialized and then an iterative rate correction is applied. The resulting scheduling offers a tractable complexity under practical knowledge of channel states and yields performance close to the corresponding exhaustive search approaches as demonstrated by Monte-Carlo simulations.