A Radio Resource Management Framework for IEEE 802.16-Based OFDM/TDD Wireless Mesh Networks

We present a radio resource management framework for the IEEE 802.16-based OFDM/TDD wireless mesh networks. The major components of the framework, namely, subchannel allocation, admission control, and route selection schemes are developed so that the quality of service (QoS) can be guaranteed on a per-connection basis. We formulate a tandem queueing model to obtain the in-connection performance measures such as average delay and packet data unit (PDU) dropping probability for relay connections in an end-to-end basis. The same formulation can be used to obtain the performance measures such as the average transmission delay for a PDU and the PDU dropping probability at a mesh-node (i.e., IEEE 802.16 base station) for local connections. Two subchannel allocation algorithms, namely, the optimal and the iterative subchannel algorithms, are proposed. The admission control and route selection schemes for relay connections are based on the performance measures obtained from the tandem queueing model. In particular, a new connection is accepted if the packet delay requirements corresponding to that connection can be satisfied and the route that provides the smallest delay is selected for routing packets through the network to the Internet gateway. The performances of the proposed radio resource management schemes are evaluated by simulations.