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

摘要

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