A Study on Wireless Agent Communication Systems

本研究致力于无线代理通信系统的实现，该系统使用了微波光子学技术的虚拟无线自由空间网络，能够提供以使用为中心的无线网络资源控制。(1)微波光子学虚拟无线自由空间网络我们提出了混沌扩频编码方法和混沌路由方法，用于直接光交换的ROF网络中多个无线空间的复用和传输，并从实验和理论上研究了它们对无线电信号传输质量的改善效果。无线代理为了实现无线代理根据用户的需求和第七层的情况对无线资源进行最优的以用户为中心的控制，提出了一种根据服务内容、用户驻留时间和无线信道质量自适应操作的无线资源管理方法，并开发了一个用于以用户为中心的无线媒体选择的SIP协议栈。我们成功地在Wireless over IP系统上演示了不同空中接口(PHS和WLAN)的终端之间的语音通信。(3)多维用户效用函数根据主观MOS实验的结果，我们推导出了一种新型的二维用户效用函数，它代表了用户对电影下载服务等待时间和图像质量的满意度。最后，我们开始搭建试验台，对所提出的无线代理通信系统进行实际测试。

This study has been addressed in the realization of Wireless Agent Communication systems, which uses virtual radio free space networks with microwave photonics technologies, and is able to provide the use-centric control of radio network resources. Followings are obtained as results :(1)Microwave Photonics Virtual Radio Free Space NetworksWe have proposed Chaotic spreading coding method and also Chaotic routing method to multiplex and transfer several radio spaces in RoF network with direct optical switching CDM, and experimentally and theoretically investigated their improvement effect in the transmission qualities of radio signals. Furthermore, optical FM method for nonlinear compensation for RoF networks, and millimeter -wave Radio-on-Radio networks for the transparent transfer of heterogeneous radio services have been proposed and examined.(2)Wireless AgentsIn order to realize wireless agents performing the optimum user centric control of radio resources according to users' demand and situations at Layer 7, we have proposed a radio resource management method operating adaptively with service contents, users' dwell time, and wireless channel quality, and also developed a SIP stack for user centric wireless media selection. We have successfully demonstrated voice communication among terminals with different air interfaces (PHS and WLAN) on the Wireless over IP system.(3)Multi dimensional User Utility FunctionsFrom results of subjective MOS experiments, we have derived a new type of two -dimension user utility function, which represent the user satisfaction for the waiting time and the picture quality for movie download services.Finally, we have started to construct a test bed to examine practically the proposed wireless agent communication system.