Downlink performance of a relay-enhanced mobile WiMAX networks

Mobile WiMAX is based on IEEE 802.16e standard to provide fixed and mobile broadband wireless access from anywhere within the metropolitan area network (MAN). Multi-hop relaying is a cost-effective approach to significantly extend the coverage and enhance the throughput and capacity of the WiMAX networks. In this paper, we evaluate the downlink (DL) performance of a relay-enhanced WiMAX networks. The effect of the number of implemented relay stations (RSs) on the performance of the mobile WiMAX networks is studied and evaluated. The performance evaluation is carried out using a system-level simulation developed in MATLAB software. The performance evaluation metrics are the average DL carrier-to-interference-and-noise ratio (CINR) and the average DL spectral efficiency. Evaluation results show that as the number of RSs is increased, the performance of the mobile WiMAX is significantly improved. However, in the scenario in which 4 RSs are deployed, the maximum achieved average DL CINR and the average DL spectral efficiency gains are 11.58 dB and 115.44%, respectively, compared to the scenario without RS.