Flexible system capacity control technique for WiMAX multi-hop relay networks

System capacity is an important factor that affects the performance of WiMAX system where the amount of data that can be delivered to the end user is determined based on the system capacity and users QoS requirements. This scenario is even more complex when multi-hop relays are introduced into the network whereas the user access capacity decreases with the increase of hop number. In order to maintain the QoS in WiMAX multi-hop relay network, it is essential to control and determine the number of users connect to each zone in regards to different levels of QoS. In this paper a Flexible System Capacity Control (FSCC) technique is proposed for WiMAX Multi-hop Relay network to control the number of users that connect to the network and calculate the system capacity in terms of a three level relay topology. We present detailed mathematical analysis of the FSCC. The FSCC control the number of users at each wireless zone by the use of different control parameters ∝ and accept or reject users at each relay based on the predefined allocated number of users for each relay and the total system capacity. The analytical result shows that the FSCC has achieved the objective of this study. Controlling and determining the number of user is very crucial in order to maximize the throughput for each individual user requirement of QoS, maintain fairness between users in the networks and guarantee QoS for real time application users.