WiMAX Forum as an organization to push the global application of 802.16 standard device, is actively organizing the interoperability tests of devices in all large system companies. Currently, WiMAX forum memebers include Intel, Siemens, British Telecom and ZTE, Huawei in China, more than 100 companies. Based on the plan made by Intel, one of the main members of WiMAX Forum, it publishes chips in the end of 2004 and realizes outdoor installation in the beginning of 2005 and indoor installation at the end of the same year. In 2006 WiMAX chip is embedded in notebook to realize its portability. With the maturation of the standard and the support of many big companies, it is helpful the realize the large scale and low cost of WiMAX technology. WiMAX will become a very powerful element to push forward the wireless broadband market. Therefore, making corresponding WiMAX application strategy is urgent for the development of operators and China Telecom industry.
WiMAX technology application strategy must be based on the existing and planned wireless networks. Because with the advantages of large transmission distance, high data rate, data and voice high quality services, and less restrictions on conditions, especially in the areas that telephone line and cable can not cover, WiMAX is very promising. The more important thing is that WiMAX not only has the advantage of traditional wideband access based on fiber and the flexibility and mobility of wireless access, but also provides the QoS support of fulfilling voice and video service applications, which makes WiMAX technique with the tent to take the place of 3G and WiFi.
The following table 1 gives the comparison between WCDMA and WiMAX. It is obvious that WiMAX and 3G have a lot of overlapping functionality and big competition, but they focus on two quite different fields of MAN and WAN seperately. They have different markets as complement for each other in netowrk arthitecture. From the perspective of WiMAX development situation, there is no direct competition between WiMAX and 3G, because although 802.16e support mobility, it is only for the roaming between wireless access system and base station. And it is not realistic to introduce 802.16e in the near future. So after the establishment of 3G network, 802.16e technique can be used as supplement. But the concrete effect of the condition of 802.16e, especially when 3G has had substantive progress and operators and device vendors have investigated a lot in 3G. We cannot expect these operators to give 3G up, and currently HSDPA technique has already been mature, which will futher limit the development of WiMAX.
Similarly compared with WiFi, the advantages of WiMAX is more obviously. as shown in table 2. But WiFi an WiMAX solve the problems of "the last 100 meters" and "the last 1 km" separately, which make them used in different fields. WiFi can use outdoor antenna making use of WiMAX to connect directly with backbone network, but not use access point to connect with wired network and then with backbone network. This largely reduces the cost of deployment of wired network. In this way, WiFi and WiMAX can develop simutaniously as complement for each other.
Furthermore, China has large area which involves various kinds of propagation environments and service needs. Based on WiMAX features of high data rate and large coverage, mix WiMAX technique and existing WiFi and 3G, there are overall considerations, such as
WiFi and WiMAX networks can be constructed simutaniously to reduce the investment of wired network; In areas without WiFi, users can access directly into WiMAX for data services.
In areas where telephone line and fiber can hardly cover, make use of WiMAX to construct wireless networks. Based on different operators' networks, in areas with weak backbone network, make use of WiMAX broadband access services as supplement of wired broadband access.
After the completion of 802.16e, WiMAX can ensure high data rate access in low speed mobility. Then it becomes the powerful complement of 3G network.
For temperary communication and large area wireless access, such as exhibition, WiMAX can be a guarantee of access.
After all, we want to establish a mixture network of 3G/WiFi/WiMAX broadband access, multi-layers, seamless coverage, co-operating network, fulfilling the as many requirements of users, and ensuring the fast development of China communication industry.
Currently the WiMAX technology is still not very mature, there is still some uncertainty in the future of WiMAX. For example, it is not an easy case to distribute spectrum in every country. But it is for sure that WiMAX will bring big opportunity and challenge to China telecom industry. The in-depth reseach of this field will be the strong base of wide future develpment for high speed network users and providers.
No comments:
Post a Comment