Research On High-Speed Railway WCDMA Network Planning And Optimization Technology

With the rapid development of the mobile communication technology and the enrichment ofbusiness types, the world has stepped into the research of the third generation mobilecommunication system and the commercial operation.As one of the three mainstream standards of3G, WCDMA is the largest commercial standards and it will have the most users in the future.Thedata on the communication industry operation issued by the ministry in July,2011shows that thenumber of3G sustribers is up to87,199million and the user permeability is near9.5percent,closeto the10percent which is the turning point of the large-scale application. At the same time, thenumber of China Unicom’s3G business and subscribers grows rapidly. With the introducement ofseries policies such as the new business pian, one thousand yuan smartphones, the development of3G will be better and the depth coverage of3G network will be futher strengthend. BecauseHigh-speed railway satisfies the user’s mobility needs and connect the different areas of thenetwork coverages and has a positive impact on the promotion of the brand, it becomes animportant area when the operators compete with each other. The wireless communication ofHigh-speed railway has a lot of challenges for its high speed such as Doppler frequency shift, thepenetration of the dody loss and region swich. Then, high-speed railway has a lot of difficulties forits varies of scenes.The paper illustrates the theory of WCDMA and combines with the high-speed railwayWCDMA network construction experience, analyzes the challenges of the high-speed railwaywireless communication,including the Doppler shifts, the penetration loss, fast cell switching andvarious communication scenes.Besides,the thesis summarizes the general practices in WCDMAwireless network construction under the high speed circumstances including propagation model,link budget, the way of coverage, switching strategies, site planning and switching setting. On thisbasis,the paper in combination with the construction of Beijing-shanghai high-speed railway inWCDMA network,and discusses several methods of the solution to the high-speed railway wirelessnetwork communication problems.In the thesis,it illustrate the different strategies in differentscenarios,such as under the elevated bridge, tunnel and other special scene.According to thedifferent scenes of the link budget,the paper gives the coverage of a cell,through the analysis oftrain speed and the handoff latency in different scene,the paper illustrates the switching overlap areasize and according to the " line capacity " of different scene,the paper gives the capacity planning of WCDMA.According to the beijing-shanghai high speed rail planning and design scheme of WCDMAnetwork in detail, based on the site survey, the article use the Atoll simulation software of Forskcompany to simulate the science,and the simulation verified the feasibility of the planningscheme.After the operation of high-speed railway, the author has test the actual network, andthrough the analysis of the test data, proving that Beijing-shanghai high-speed railway WCDMAwireless network construction project has achieved excellent coverage and reached the designrequirement of the project.