A Study Of WCDMA Wireless Network Incipient Programming In SiPing City

1. IntroductionWith the development of the mobile communication technology, the gradual maturity of the 3G standard and equipment, and the coming of the end of national 3G test net testing phase, the commercial period of the national 3G are near. It is predicted by the experts that China may grant license of 3G at the end of the 2005. At this premise, China mobile communication company, as the largest GSM mobile network carrier, must well prepare for the future competition by means of development of the network and careful study of the 3G layout ways.Siping communication sub-company is the branch of the China mobile communication Jiling Company. At such a background, the main content of this article talks about the beginning layout plan of the Siping urban WCDMA wireless network, by using WCDMA wireless network theories and methods, And the results of the study are for the reference of future Siping urban network construction, and for others company of China mobile network .2. Discussion of the relevant problems of wireless network planning of WCDMAWCDMA technological system is the key net gradual progress based on GSM/GPRS network, can be because of TDM while keeping the compatibility with GSM/GPRS network (Time Division Multiplex, is it spend to reply time), , to the whole IP network structure gradual progress ADM (Add/Drop Multiplex , is it is it is it use to reply to insert to divide into ) and IP technology. This technical standard has been already ripe, but has not entered overall construction yet in our country, accord with our country real networking scheme still during the course of testing the network ,, especially network planning is it draw lessons from to have no experience. And its overall construction must follow two prerequisites : First , realize originalGSM network carries out the transition to the smoothness of 3G network , namely is realizing not having in order to link up technically, economically avoid repeated construction; Second modern techniques characteristic given full play to the newly-built network. In order to guarantee these two prerequisites, need comparing with the basic network technology characteristic of the two, study the problem to be solved of WCDMA networking, analyse that it distinguishes and gets in touch to draw the two network planning, give security for networking and feasibility and science of planning.Such technical standards as systematic structure , interface of the network , key technology , business treatment environment of WCDMA ,etc. have already been released , WCDMA networking face on one hand come from CDMA many location way inherent large location not to interfered and interfere the problem directly more; Come from the environmental mobile communication faced in WCDMA system on the other hand. This forms and utilizes WCDMA technology to implement the main content solved in network planning too.Compare with the difference between GSM and wireless network planning of WCDMA and reflect in 8 following respects mainly:Distance effect issue, up chain and down chain, capacity and dependence that cover (whether district breathe the effect), covering the relation with power of base station, the circuit type business is different from data type business, WCDMA soft to switch over function, WCDMA need carry on complicated frequency plan , lead pollution problem frequently. Compare with and does not publish uglily , the wireless network planning of GSM system is that the capacity and covering in the district is tried to get a bit more bestly between the two, and should seek a bit more bestly among the three in capacity , covering , different service qualities in wireless network planning of WCDMA system. This is key goal of network planning of WCDMA and main content too.3.WCDMA wireless network the theory of planning plan in advance3.1Wireless network planning content analysis and procedure WCDMA are set upThe content of wireless network planning o f WCDMA is divided into and planned in advance generally and detailed planning and network on later stage optimize three parts. Combining WCDMA network characteristic, it should include chain budget , capacity and plan , stand and count andestimate several main contents to plan in advance.Through being systematized in network planning to WCDMA , subdivide the course of wireless network planning of WCDMA, set up wireless network planning procedure the following of WCDMA (such as Fig. 3-1).Capacity goal ^rChain budgeCover the gOJHQuality goabThe radius of the district is estimatedStand and count estim ating| RNC counting and I estimatingStand in the locationDetailed planning stage ! Fig.3-2 Plan the flow chart in advance3.2WCDMA network plans the settlement of the key problem in advance1) The network inputs ofs outputting, can know according to WCDMA characteristic analysis to require up load should be in 30%0% to cover with; Should combine WCDMA business carry on different conversion of unit in traffic model that capacity's demanding choose, not only consider communication probability also should be decided by and served the grade in the quality requirement.2) Planning the procedure and content in advance can be stated from the chart of making:Capacity goalCover the goQuality g O a ijChain u d g eThe radius of the district is estim atedStand and count estim atingRNC counting andestim atingStand in the location; Detailed planning stage Fig.3-2 Plan the flow chart in advance3) WCDMAchain from upgo chain begin budget. Upgo and interfere the limiting factor that is usually CDMA. The adoption formula of the up chain budget is:PL_UL - Pout_UE + Ga_BS + Ga_UE - Lf_BS -Mf-MI-Lp-Lb-S_BSThe formula is:PL_DL=Pout_BS - Lc_BS - Lf_BS + Ga_BS + Ga-UE - Mf - MI - Lp -Lb - S_UE4) Propagate models to analyse that selects Hata for use to revise the model (Okumura-Hata model ) while planning in advance. Model this according to village experience formula that curve graph make, Hata model regards spreading and lossing in the urban area as the standard, other areas revise on this basis. The standard formula lossed in route of urban area is:L (Urban area) = 65.99 + 26.161ogf - 13.821ogHb - a(Hm) -(44.9-6.551ogHb)logd4. Study of WCDMA Wireless Network Incipient Programming in Siping CityThis article talk about the results of the wireless network largely depends on the carrier's network construction strategy. And suggests the coverage area, coverage target, capability target and etc. on the basis of Siping city GSM network condition, the development of the 3G users in the layout period, the harmonious construction of the GSM and WCDMA, the analysis of the beginning part of the construction plans, the quality and economy of the layout and network construction and the convenience of the improvement of the network. It also estimates the average inter-station distance and makes the beginning construction pre-layout plan of the Siping urban WCDMA wireless network based on the analysis of the beginning layout network characteristics, link prediction methods and spreading model.The result is that to realize the continuous coverage of the CS 12.2k voice service and CS 64k video telephone service in the general urban area and the out of important groups at the beginning layout period (the end of 2006) needs 27 WCDMA wireless macro base stations in the Siping urban area. The type of all the stations is single frequency three sectors. The network is designed for high load. The surplus is 50%. The future expanding capability priority frequency adding modes, together with the original GSM base station, occupy the 96% of location.