| Wireless mesh networks(WMN), which is a newly wireless multihop networks, consist of mesh routers and mesh clients, where mesh routers have minimal mobility and form the wireless backbone network to provide network access for mesh and traditional clients. Compared with traditional network, WMN has many merits, such as flexible construction, low upfront investment, high coverage, etc. WMN usually provides internet access for the areas with no optical fibre as a wireless backhaul network, provides extensiveness internet access as a WMAN, and can also apply to emergency response administration, military or police communication systems. Recently the WMN has been supported by many open standards such as IEEE 802.11, IEEE 802.15, IEEE 802.16, IEEE 802.20, etc. WMN becomes the research focus for its broad prospect of application.In this dissertation,we consider the resource management of wireless mesh networks based on game theory, evolutionary computation technique and convex optimization theory,etc. The dissertation focuses on Media Access Control(MAC) scheduling technology and rate allocation in particular.The main contributions are listed as follows:1) A dynamic approach for transmission holdoff time in IEEE 802.16 mesh mode with Coordinated Distributed Scheduling scheme is proposed. This scheme allows different nodes to use different holdoff time values according to current node need of the control-plane bandwidth. Nodes that need to establish data scheduling use small Xmt-Holdoff-Exponent, while others use large Xmt-Holdoff-Exponent. Simulation results show that the proposed dynamic approach can reduce unnecessary transmission delays and improve network throughput.2) Rate allocation for elastic flows is investigated. Supporting quality of service for different traffics in IEEE 802.16 wireless mesh network is a hot topic in WMN. The problem of resource allocation problem in IEEE 802.16 wireless mesh networks is studied in this dissertation, a resource allocation algorithm based on the cooperative game theory of Nash bargaining solution (NBS) for multi-radio multi-channel networks is proposed. In the proposed algorithm, the NBS mechanism is combined with the adaptive modulation, channel allocation and multi-radio multi-channel interference model for the end-to-end traffic flow in IEEE 802.16 wireless mesh networks. Bargaining power is used to ensure the quality of service required by the traffic flows. Each user can obtain its rate allocation scheme in distributed and decentralized manner, and compete resources cooperatively. The proposed algorithm ensures the quality of service of traffic flows with high class and throughput of the whole network. Simulations show that the proposed algorithm can effectively improve the performance of the whole network to Pareto optimality and the quality of service of different traffic flows.3) Rate allocation for inelastic flows is investigated. Combined with the adaptive modulation and- coding technology, the rate allocation for inelastic flows is modelled as the nonconvex optimization problem of network utility maximization (NUM). Since the nonconvex optimization problem is generally NP-hard, and is not easy to solve. Nowadays there is rare research on nonconvex optimization problem, while particle swarm optimization (PSO) can solve discontinuous, nonconvex and nonlinear problems efficiently, an rate allocation algorithm for inelastic flows using particle swarm optimization implemented in an central way is proposed. It is proved that the proposed algorithm converges to the optimal solutions in this dissertation.4) Based on achievement 3) and considered the high complexity of the centralized optimal algorithm, a heuristic rate allocation algorithm for inelastic flows in distribute way is proposed. Simulations show that the proposed algorithm can assure the minimum rates requested by inelastic flows when the network capacity is not enough, and converge to the optimal solutions when the network capacity is enough.What is noteworthy is that the ideas and conclusions described above are based on IEEE 802.16 WMN, but the ideas may also be applied to other wireless mesh networks.
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