Wireless Network Optimization For PHS

PHS (Personal Handyphone System) is a personal wireless communication system belonging to the second generation mobile communication. It was developed by the RCR (Research and Development Center for Radio Systems) of Japan in the early 1990s and its criterion standard is RCR-STD28.The construction of the PHS network in Shanghai began in 2002. It has a rapid development and the subscribers have been over 1,000,000. At present, the system has some problems such as short of signal overcast, breaking off of the communication and frequent handover, etc. All these problems have affected the service quality. So it's necessitous to do some optimization for the wireless network.For the good of optimization of the network, first we need to analyze its principle and know something about the structure, mechanism and flow of the space access.The prediction of the propagation of electromagnetic wave is most important in urban areas where subscriber density is high, and the buildings have a profound influence on the propagation. In this dissertation, we found a propagation model to analyze the path loss and an arithmetic based on ray tracing octree technique for the propagation prediction. This gives the theoretical foundation for the optimization of the PHS network. The most transmitting power of the base station is only 500 mW, and the frequency band used in PHS is 1900 MHz, so there is a great loss of energy along the transmission path.The optimization of the PHS wireless network is a long and tough work. Firstly we gather the operating data from the software of the network management or using the measurement tools; secondly we analyze the data and find the problems in the wireless network; thirdly we find the methods to solve these problems. Some methods for the typical problems is given, this will accelerate the optimization.There is a short history of the optimization in Shanghai, and we must learn and accumulate experience during the practice. At the end of this dissertation, we give several typical cases of the wireless network optimization with the models and methods given in this dissertation.