Distributive Subband Allocation, Power and Rate Control for Relay-Assisted OFDMA Cellular System with Imperfect System State Knowledge

TL;DR

This paper proposes a distributed resource allocation method for relay-assisted OFDMA systems that optimizes fairness and throughput using local imperfect information, reducing signaling overhead and computational complexity.

Contribution

It introduces a fast-converging distributed solution with reduced feedback for relay-assisted OFDMA systems, achieving near-optimal performance with minimal overhead.

Findings

Achieves asymptotically optimal throughput with small feedback per user.

Provides a distributed algorithm that converges quickly using local imperfect CSIT.

Derives asymptotic average system throughput for system design insights.

Abstract

In this paper, we consider distributive subband, power and rate allocation for a two-hop transmission in an orthogonal frequency-division multiple-access (OFDMA) cellular system with fixed relays which operate in decode-and-forward strategy. We take into account of system fairness by considering weighted sum goodput as our optimization objective. Based on the cluster-based architecture, we obtain a fast-converging distributive solution with only local imperfect CSIT by using decomposition of the optimization problem. To further reduce the signaling overhead and computational complexity, we propose a reduced feedback distributive solution, which can achieve asymptotically optimal performance for large number of users with arbitrarily small feedback overhead per user. We also derive asymptotic average system throughput for the relay-assisted OFDMA system so as to obtain useful design insights.