The Study Of Difficulties In Gsm Wireless Network Optimization

The coverage of the GSM network is enlarged everyday, the category of its service is increased, and the terminal cost is decreased, while the number of the GSM network user is springing. At present, the third generation of the China Mobile network is used in commercial affairs in several cities. Whereas, in a relatively long term, the user of GSM network will still increase and the GSM network still shoulder most of the voice and data services. Since it is affected by investment, projection, and the unproportionate distribution of the user, there emerge the problems about regional traffic absorption and the voice quality in GSM network. Among those problems, the taffic absorption and guarantee of quality in high density area, high building coverage and voice quality, and the guarantee of voice and data services in university campus are urgent which need to be solved as soon as possible.This thesis provides solutions to the above mentioned three problems by analyzing the basic theories of GSM Network Planning and Optimization.About the first problem, which is about taffic absorption in high density area, the thesis analyzes regular solutions, for instance, cell division, outdoor femtocell station, indoor femtocell, and compares the advantages and disadvantages of different solutions. Then, according to the reality of Pingdingshan city, a three-dimensional network construction method which involves "macrocell+street station+indoor femtocell" is settled. Through the construction of three-dimensional network, the bearing capability of the network is risen and the demand of traffic in high density area is fulfilled. The street station and indoor femtocell undertake part of the traffic of the macrocell. As a result, the TRX configures and coverage of the macrocell decrease. The intersecting coverage between different macrocells and the inner inferference decrease, too. Then, the quality of the network is apparently improved.The second is about the voice quality in high buildings. The current indoor coverage is optimized through "multi-layer coverage". At the same time, for the community in upper floors of high buildings, the method of setting one-way and adjacent communities, combined with the optimization of the parameter, successfully solve the low quality voice problem caused by frequent handover between indoor cell and outdoor cell.The third is about the university campus where the data services are concentrated, seriously congested, and the speed of download is slow. This thesis originally proposes a "traffic division" method, which means to construct indoor distribution system inside the dormitory buildings. A separated macrocell is used as source of Indoor Distribution. As a result, the services of the whole campus are divided into several indoor distribution cells. The optimization of the parameters, together with the above mentioned means, are applied to balance the traffic of the macrocell and the source cell of Indoor Distribution. At last, the congestion problem in university campus is solved, which effectively rises the speed of data download and the user's feelings.