Resource management issues for multi-carrier relay-enhanced systems

Relaying is one of the enabling techniques for next generation systems. Factors deciding on performance of relayenhanced systems are the resource allocation and coordination. The capacity of the wireless relay backhaul link is typically the bottleneck of transmissions conveyed through the relay node. It can be to some extent improved by allocating dedicated resources; however, typically this is done at the expense of the performance of users served directly from the base station. To achieve optimum overall performance, resource assignment to relays and users has to be done carefully. This article addresses the problem of resource allocation with relays operated in multicarrier scenarios. Guidelines for optimization of the resource allocation under the resource fair policy are given with different relay configurations, including time, frequency, and hybrid resource partitioning schemes. Finally, advanced resource coordination procedures are presented. Multi-carrier interference coordination is proposed for improving the quality of radio links, and carrier load balancing for improving the efficiency of resource utilization.