Research And Application Of Wireless Access Technology Based On WiMAX

With the continuous development of science and technology, it has been the diverse needs of the expansion, especially for the requirements of communication technology, people want to be able to get a higher transfer rate, better mobile performance and service quality.The current data are still cable access business-oriented, the traditional fixed-line operators, because a large number of wireline access resources and access data services accounted for the lion's share of the market. Other operators has little local network resource and capacity, although the capacity of backbone network transmission and business, so local network becomes the bottleneck of data access business development.Local network required a longer construction period and substantial investment, in terms of opportunities for market point of view or from the perspective of return on investment than the large-scale construction of local networks are not realistic. WiMAX solve the "last mile" problem of access.1999, IEEE established the 802.16 working group to study broadband wireless access technology standards,who's aim is to establish a unified global broadband wireless access standard. Two IEEE802.16 standards are mainly refered currently: 802.16d fixed broadband wireless access standards and characteristics of 802.16e mobile broadband wireless access standard. In October 2007, WiMAX standards formally the International Telecommunication Union (ITU) approved 3G standards for the fourth, its access to global harmonization of spectrum cleared the obstacles. Since then, the WiMAX operators on a more positive attitude, and is no longer limited to fixed operators, mobile operators are also interested in the technology to start and add to the test ranks.1.This article describes two aspects of WiMAX technology, WiMAX Protocol Architecture and key technologies.In the WiMAX Protocol Architecture, it takes the physical layer and the MAC layer as key points, and introduced three sublayer of the MAC layer(service specific Convergence Sublayer, common segment sublayer, security sublayer) and the topology, QoS machine-made and safety mechanism of the supports of the MAC layer,.It explained fully how WiMAX is called the wireless broadband access technology to face the telecommunication operation, to have truly QoS the guarantee, to have the global standardizetion.OFDM, OFDMA, MIMO, HARQ, AMC are analysed basing on the understanding of WIMAX protocol architecture.The application of these technologies fully demonstrated the technology at the WiMAX transmission distance and high transmission speed, high capacity, flexible channel width, QoS performance, rich multimedia communication services, reliable security advantages. 2.This article emphatically has carried WiMAX and the Wi-Fi, WCDMA, CDMA2000, TD-SCDMA broadband wireless access technology the comparison. But besides the WiMAX technology, the existing broadband wireless access technology also has Wi-Fi, WCDMA, CDMA2000, TD-SCDMA and so on. Through these comparative analyses of the WiMAX technology and other similar relations, the key is WiMAX and the original 3G technology relations. WiMAX, Wi-Fi and 3G these three kind of technologies have many overlap functions, but they have their own market position, more so is a complementary relationship, there is also part of local integration.3.Combined with the development of WiMAX technology, WiMAX of a new stage of business applications were proposed.At present, more mature WiMAX equipment based on 802.16d, mainly at this stage to carry out the proposed NGN access, broadband data access, data line access, Wi-Fi backhaul business.4.Combinating engineering practice, the article thoroughly researches the WiMAX wireless access solution. Mainly aims at the following several aspects:(1) business forecastThe internet access and IP access service of party and government organs, education and scientific research institutions, industrial and commercial enterprises, social groups and information community are predicted, taking into account other business data appropriate bandwidth is reserved. This paper presents the results of prediction and prediction.(2) business organizationWiMAX is based on Ethernet technology, WiMAX can not directly address the way TDM-based service access. In practical applications, WiMAX as a major cable network, it is difficult for the cable network to provide coverage of the data access or relay.(3) NetworkIEEE 802.16d based on the 3.5GHz point-to-multipoint broadband wireless access system is adopted. The system is point-to-multipoint topology, mainly by the base stations, terminals and network management systems constitute the majority of three. Terminal through a wireless link to receive the signal the base station, base station stops to the city through the transmission network and IP core network.(4) frequency planningCross-sector coverage brought forwarded in order to avoid frequency planning brought about by the increase in complexity, to avoid polarization phenomenon with the same frequency to avoid interference with a solution.(5) the base station accessTransmission capacity allocation in accordance with the base station and base station location and data networks, the solutions are proposed in this paper.(6) Network Management System According to the characteristics of equipment, the network management system is constructed. It is Recommended of the establishment of a network management hardware platform for network management through the band for base station and subscriber station configuration management, performance management, security management and fault management. In addition, the proposed configuration of mobile terminals for control system maintenance.(7) the user accessThe solution is brought forwarded for Group Customers, individual users, IP telephone booth, mobile communication base stations.On the basis of fully analyzing the WiMAX technology, this article explained that WiMAX had huge superiority of the aspect of wireless broadband access in the present stage, and proposed the effective WiMAX wireless access solution, it will be provided advantageous support and possibility for the WiMAX technology from the theory to the practical application .