Research On Routing Protocol Based On Power Control For Multi-Radio Multi-Channel Wireless Mesh Networks

The Multi-Radio Multi-Channel Wireless Mesh Network (MRMC-WMN) draws significant attention because of its excellent throughput performance, robustness and relative low cost. The closed interactions among power control (PC), channel assignment (CA) and routing can contribute to the performance of Multi-radio Multi-channel Wireless Mesh Networks (MRMC-WMNs). Most of existing researches on the joint optimization usually only consider one or two of these three technologies. However, the joint PC, CA and routing (JPCR) design, which is desired to achieve a global optimization, has seldom been addressed.This thesis begins with a survey of the wireless Mesh networks, including the basic definition, characteristics, network architectures and application scenarios. Then the existing routing protocols for MRMC-WMN are surveyed and analyst, based on which we think the joint optimization of power control, channel assignment and routing has a strong feasibility and is very necessary.Based on the conclusion above, we first present a routing algorithm joint with PC and CA called Joint Power Control, Channel Assignment and Routing Algorithm (JPCRA) to find the routing, power and channel scheme for each flow, which aims to improve the fairness performance. Firstly, considering available channels and power levels, the routing metric, called minimum flow rate, is designed based on the physical interference and Shannon channel models. Then the JPCRA is presented based on the Genetic Algorithm with Simulated Annealing (GASA) to maximize the minimum flow rate, which is an NP-Hard problem. Simulation results show the JPCRA obtains better fairness among different flows and higher network throughput.As a centralized algorithm, the JPCRA algorithm has some problems in terms of complexity and network overhead. So this thesis presents a distributed routing protocol joint with power control and channel assignment called Distributed Power Control, Channel Assignment and Routing (DPCR), which aims to improve throughput and end-to-end delay performances. Taking the interference, channel occupancy and delay into consideration, we define the interference penalty factor, channel occupancy factor and weighted average expected transmission time, based on which the metric for the single-hop and for the whole route is presented. Using local information, nodes calculate the optimum power and channel for each of their neighbor node. The source and destination nodes select optimum route according to the routing metric. Simulation results show DPCR can effectively control the network overhead, improve the throughput, and reduce end-to-end delay, as well as the power consumption.