Other Wireless Networking Technologies
This chapter has delineated and briefly described some of the wireless net- working technologies that are expected to compete with or compliment WiMAX. Other technologies will most certainly emerge and as such may change the marketplace climate for WiMAX and related technologies signifi- cantly. Such technologies include
The Wireless Broadband (WiBro) standard, a Korean standard that is incorporated into the IEEE 802.16e standard. While the WiMAX Forum has indeed created certification profiles for IEEE 802.16, it is unclear as to what degree the WiMAX Forum will certify WiBro- enabled equipment. This could affect deployment of the WiBro technology.
The IEEE 802.22 wireless regional area network (WRAN) standard is currently emerging and aims to employ cognitive radio concepts to enable a next-generation adaptive wireless networking technology operating in the licensed broadcast television bands.
Competing Technologies
Some of the wireless technologies described here will undoubtedly compete with WiMAX and its associated technologies. This section of the chap- ter provides a discussion of such technologies and what advantages or disadvantages each has when compared to WiMAX.
1.7.1 IEEE 802.20
The IEEE 802.20 working group and IEEE 802.16 Task Group E have been widely considered as developers of competing technologies. However, there are some differences between the two standards:
IEEE 802.20 aims to develop a standard that supports 1 Mbps data rates for mobile users moving at speeds up to 250 km/h. IEEE 802.16e, however, only supports users at vehicular speeds, notionally up to 150 km/h.
IEEE 802.16e is intended for frequencies operating from 2–6 GHz. However, IEEE 802.20 is focused on frequencies at 3.5 GHz or below.
IEEE 802.16e is based on prior IEEE 802.16 standards work, while IEEE 802.20 aims to produce an original standard.
IEEE 802.16e is a ratified standard while IEEE 802.20 is still in the draft form. Furthermore, contention in the IEEE 802.20 working group may prevent any final version of the standard, similar to what has happened in the IEEE 802.15.3a working group.
It is expected that IEEE 802.20 will not support the high data rates that IEEE 802.16 provides, as the solution space for IEEE 802.20 focuses on high- speed mobility. However, as the IEEE 802.16e standard evolves and WiMAX profiles are defined for various mobility classes, advancements in technology and methods could improve mobility support up to and surpassing speeds defined in IEEE 802.20 for implementation-specific IEEE 802.16e equipment. Furthermore, a wide variety of industry participants have embraced IEEE
802.16 and WiMAX certification as the path to broadband wireless mobile access, although IEEE 802.20 aimed to produce a standard that achieved this vision.
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