A novel route selection strategy in decode-and-forward relay enhanced LTE-A network

Decode-and-forward (DF) relay has been proposed as a promising technique in LTE (Long Term Evolution)-Advanced to expand cell coverage and improve system performance. Due to the large discrepancy between uplink and downlink capabilities of donor eNodeB (eNB) and Relay Node (RN), the conventional strategies which are based on downlink optimisation lead to some users connecting to the nodes which provide better downlink performance but poorer uplink performance. In this paper, a new route selection strategy is proposed, which considers uplink and downlink jointly. The proposed route selection strategy is compared with a conventional strategy based on downlink spectrum efficiency. Simulation results demonstrate the advantages of the proposed strategy in enhancing system uplink throughput and increasing user´s uplink spectral efficiency with no or little degradation of downlink performance.