Load Based Relay Selection Algorithm for Fairness in Relay Based OFDMA Cellular Systems

A load-based relay selection algorithm that improves the fairness of resource allocation is proposed for relay-based OFDMA systems. This algorithm takes into account the traffic load condition (bandwidth requirement) of relay link users and direct link users. The transmission mode (direct transmission mode or relay transmission mode) of each user will be adjusted based on the user average data rate; this will make the long-term average data rate of relay link users and direct link users equal so that user fairness is enhanced. The simulation results show that the proposed algorithm will improve the user fairness compared with a popular traditional relay selection algorithm, for both uniform distribution and hot-spot scenarios.