The Study Of Channel Allocation Strategies In Gprs Networks

With the constant development of Mobile Communications Technology, Data Service is raising the proportion more and more in Mobile Communications. Nowadays, various wireless data serviee have already been operational, but operators and terminal users still pay more attention to general packet radio service(GPRS)based on GSM network because of its many advantages. GPRS is one of GSM Phase 2+ section, it can supply different transmission speed and effectively make use of wireless resources, which is the first step of the evolution of GSM network towards the third generation mobile communications. GPRS system, based on GSM network, use current GSM wireless network and share the same base stations and spectrum resources with GSM. Before 3G service is extensively used, it's still the most important problem how to ensure the qualities of voice service and data service and reasonably distribute GPRS information channels.The traditional way of distributing voice service and data service is known as fixed boundary dynamic channel allocation(FB DCA)strategy, According to this strategy, voice service can only use the information channel of voice service, and data service can only use the information channel of data service. To preferably make use of system resources, we introduced the strategy called mobile boundary dynamic channel allocation (MB DCA) strategy, and utilized Markov. Process model to analyze theoretically them respectively, then got the results of voice call blocking rate, the packet queue length, average packets waiting time, losing rate and the utilization efficiency of the total system. Besides, we built up simulation model and testified the theoretical analysis results of two projects. Theoretical analysis and simulation results both make clear that compare with FB project. MB project improved the utilization ratio of information channels and enhanced the performance of data service on condition that the effective reach of voice service is low and the performance of voice service isn't changed. After that, based on it, the MB DCA strategy is introduced, which increases the performance of the whole network through providing reserved channel for switching call.