A Multicast Mechanism in WiMax Mesh Network

The IEEE standard 802.16x based broadband wireless access is a promising technology to provide wireless broadband connectivity. Besides the Point to Multi-Point mode, a mechanism to create multi-hop network through Mesh mode is defined for the frequency spectrum band 2-11 GHz. However, the standard only defines unicast transmission in the mesh mode, the mechanism for multicast is not specified. This paper proposes a novel multicast strategy in WiMax mesh network by building a high efficient multicast tree with utilization of scheduling messages defined in the standard. An easy to implement tree construction algorithm is presented based on the adjustment of the centralized routing tree. Simulation results show the multicast mechanism improves transmission efficiency and reduces group latency over the traditional way to fulfill multicast by unicasting.