Dynamic Distributed Resource Allocation in Relay Assisted OFDMA Networks

Relay assisted OFDMA networks are promising solutions for provision of high-data-rate services in wide coverage areas. However, the deployment of relays makes the resource allocation a more challenging and complex task. In this paper we study dynamic allocation of power and subchannels in an OFDMA downlink system with regenerative relays which have the capability of buffering the users’ data to transmit in a suitable time. We model the network as a multicell scenario with small serving areas and provide a novel framework for resource allocation, in which each of the relays and BS allocate resources based on the queue and channel state information of their own users. We propose Dynamic Distributed Resource Allocation (DDRA) algorithm for this purpose, where BS and relays decide about the allocation of the power and subchannels by passing messages among themselves and based on the local queue and channel state information. Simulation results show significant improvement in terms of system throughput and users queue stability. Keywords-OFDMA; regenerative buffering relays; dual decomposition; distributed resource allocation.