Scheduling and channel assignment algorithm for IEEE 802.16 mesh networks using clique partitioning technique

The IEEE 802.16 standard for wireless metropolitan area networks, also known as WiMAX, is defined to meet the need of widespread broadband wireless access and provide a cost efficient alternative to cabled access networks. This paper proposes a channel assignment and a centralized scheduling algorithm for multi-channel IEEE 802.16 mesh networks. In channel assignment, clique partitioning technique is used to find out the set of links that should be assigned the same channel, so that the number of channels required to eliminate secondary interference is minimized. In scheduling, a priority scheme has been proposed, which avoids accumulation of packets in any node of the network. Clique partitioning technique is used to select the optimal set of links having maximum priority for transmission in each time slot. Simulation results show that our channel assignment algorithm minimizes the number of channels required to eliminate secondary interference, and our scheduling algorithm minimizes the length of the scheduling cycle as well as the size of the relay buffer required for the nodes. In addition, in case sufficient number of channels is available, our scheduling algorithm requires relay buffer of unit size for all nodes in the network, independent of the network traffic.