Abstract:
One of the most important features of IEEE802.16e is the ability of sophisticated QoS
provisioning. The basic approach for providing the QoS guarantees in IEEE 802.16e is
that the uplink and downlink scheduling at the base station (BS). To maximize usage of
available resources and take advantage of the varying channel condition at the subscriber
stations (SSs), adaptive and dynamic scheduling techniques are typically used. After
making the scheduling decision, the BS informs all SSs about the scheduling decision at
the beginning of each frame using the MAP messages. In this paper, we propose a new
adaptive resource allocation and scheduling scheme for RT-downlink traffic in a single
cell MIMO-based IEEE802.16e broadband wireless system. Our scheme is based on
cross-layer approaches, which improves system performance in terms of increasing
system throughput and provide better quality of service for users in terms of reducing
Head Of Line (HOL) packet delays. We use a utility based framework to provide the link
between physical layer and data link layer. In this architecture a new utility function is
used. The subchannelization scheme we used is based on contiguous subcarriers in
WiMAX is called band adaptive modulation and coding (AMC). To improve throughput,
adaptive modulation and coding (AMC) at the physical layer is used. We provide
simulation results comparing our proposal with different schemes. The simulation results illustrate the superiority of our scheme for different channel conditions and different numbers of active users in the system.