Resource and QoS optimization for multicasting in mobile WiMAX networks

WiMAX is based on the standard IEEE 802.16e-2009 for wireless access in Metropolitan Area Networks. It is one of the solutions for 4G IP based wireless technology. WiMAX utilizes Orthogonal Frequency Division Multiple Access which also supports Multicast and Broadcast Service with appropriate Modulation and Coding Scheme. Presently, Scheduling and Resource allocation algorithm in Opportunistic Layered Multicasting provides multicasting of layered video over mobile WiMAX to ensure better QoS. Scheduling in Video base layer and enhancement layer is done by pseudo randomly selecting subcarriers to form a sub-channel which may result in the selection of weak subcarriers. The proposed work deals with the selection of the subcarrier to the user, where instead of pseudorandom selection of subcarriers a knowledge based selection of subcarrier is carried on which in turn will offer better QoS and users are scheduled to provide the maximum utility. The optimal subcarriers are identified based on the subcarrier strengths. The simulation results show, with knowledge based selection for both video base layer and enhancement layer, the throughput is enhanced and error rate is substantially reduced.