Deployment of Wireless Multi-hop Networks in Practical Environments
ナムシーンプ ラースビラム, Namzilp Lertwiram · Institutional Repositories DataBase (IRDB) · 2013
Low latency and high reliability systems are required for future applications of Wireless Sensor Networks (WSNs) in autonomous systems.Since WSNs consist of numerous sensor nodes distributed in the target area, the deployment of relay nodes is necessary to help sensor nodes, which cannot directly connect to the sink, to transfer data.One of the efficient ways to deploy relay is to construct multi-hop relay networks as supporting backbone to the WSNs.To maximize the network performance, however, network designers still confront with challenges in deploying multi-hop networks in WSNs, especially the determination of optimum relay placement and the exploitation method of Multi-Input Multi-Output (MIMO).These two issues have been investigated in several researches based on theoretical models, which are almost impractical since they do not consider the effect of shadowing caused by obstacles typically existing in realistic environments.Therefore, the main contribution of this dissertation is to provide the deployment methodology of multi-hop relay networks in practical environments, mainly subject to optimize the relay node placement and network performance.To achieve this objective, we conduct the propagation measurement experiment and 3D ray-tracing simulation to obtain the information of MIMO propagation channels in realistic environments for using in our studies.In this dissertation, we first study the performance of MIMO multi-hop relay networks in a real shadowing environment by adapting several relaying schemes, which have been theoretically investigated so far, to verify the best method of achieving high network capacity.Together with the performance optimization of multi-hop networks based on different relaying schemes, we also investigate the optimum relay locations.Finally, with the similar analogy, we design a deployment methodology of backbone network for WSNs, which the network designers can use to find the best relay locations and fully exploit MIMO technology to obtain the best network performance.