Research Of Spectrum Resource Optimization And Multi-channel Technology In Wireless Network

In the wireless network, the available spectrum is a bottleneck of network capacity. While, effective spectrum resources assignment strategy can reduce network interference, improve the utilization of spectrum resources. Wireless mesh network (WMN) is a new kind of broadband wireless access networks, spectrum resources assignment and multi-channel technology is essential for wireless mesh network.First of all, this paper introduces the concepts and overviews of spectrum resources assignment problem, including the classification of channel assignment and the algorithm models. Then, investigate the applications of channel assignment in wireless cellular network, including static channel assignment, dynamic channel assignment and hybrid channel assignment, and analyses channel assignment algorithm with several coloring models for cellular networks.Secondly, this paper focuses on the channel assignment researching in wireless mesh network, and discusses the constraints conditions of the algorithm, analyses the typical channel assignment schemes also. Under virtual hierarchical wireless mesh network structure, this paper proposed it's channel resources assignment by introduced RF-based defense degree as the indicator of channel assignment, and proposed a generalized set T-coloring model which could maintain network connectivity and control wireless channel interference for resources assignment.Finally, this paper proposed a slot channel assignment scheme based on graph decomposition in multi-radio multi-channel wireless mesh networks by extended channel assignment in the time domain. A new algorithm based on of the transmission paths between communication nodes in each time slot corresponds to a sub-graph, and every sub-graph using a certain coloring algorithm optimizes channel assignment in each time slot. Consequently, each time slot more link can be assigned channels and network throughput can be improved. The scheme takes the precedence to other channel assignment schemes. The simulation results show the effectiveness of the algorithm.