Adaptive subcarrier allocation and relay selection schemes in relay-enhanced OFDMA systems with proportional constraint

In this paper, we study adaptive resource allocation algorithm in multi-relay-enhanced OFDMA systems and propose new relay selection and subcarrier allocation schemes. Previous works only focused the traditional optimization problem with total power constraints in the base station (BS) and each relay station (RS). While in our results, we introduce a new proportional constraint which denotes different quantity of service (QoS) of different service. We approach this problem using max-min method based on average power allocation (APA). Simulation results show that the proposed schemes perform well.