In this paper we have proposed a multimedia supported uplink scheduler for IEEE 802.16d OFDMA network, which includes a proportional fair (PF) scheduler in base station (BS) and earliest due date scheduler (EDD) in subscriber station (SS). The PF scheduler in the BS allocates the OFDMA resources to each SS according to their bandwidth request. The EDD scheduler in the SS utilizes the allocated resources according to the packet deadline thus provides QoS guarantee. The proposed system is simulated using C programs and extensive simulation results were presented. The simulation is carried out with varying OFDMA frame size (5msec, lOmsec) and coding rates (16QAM CTC 1/2, 16QAM CTC 2/3) and the throughput and delay performance is compared. Our results indicate that the proposed scheduler performs well for VBR applications with excellent delay guarantees and improved throughput.

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This paper proposes a mechanism that supports Always Best-Connected (ABC) Quality of service (QoS) to the application in a heterogeneous network. The heterogeneous network consists of IEEE 802.11e WLAN and IEEE802.16d WiMAX access networks. The User Equipment (UE) in the network is enabled with both WLAN and WiMAX access capabilities. The Generic Virtual Link Layer (GVLL) is placed above the WLAN and WMANMAC layer in the UE, decides the best serving access network in terms of QoS support. The best access network is chosen dynamically based on the QoS parameters such as throughput, packet loss, and delay. The main focus of this work is to provide QoSfor Variable Bit Rate (VBR) multimedia services in a heterogeneous network The simulation results show that the performance of the users in the network is improved significantly in terms of throughput, delay, call admission because ofthe support ofheterogeneous nature.