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The business of wimax - Pareek D.

Pareek D. The business of wimax - Wiley publishing , 2006. - 330 p.
ISBN-10 0-470-02691
Download (direct link): thebusinessof2006.pdf
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Despite its wide range of spectrum options, the WiMAX Forum is focusing its efforts on the frequency range from 2 to 11 GHz.
Benefits of 2-11 GHz
At these frequencies, radio waves can penetrate some way into buildings, and can bend and reflect around obstacles to some extent, so the base station and client antennas do not need a clear line-of-sight between them, which is much more practical in an urban environment. However, there is also another significant consequence due to the nature of spectrum regulation.
Different versions of WiMAX are defined at these lower frequencies, partly as a result of differing national regulations governing wireless spectrum. For example, a frequency at 3.5 GHz requires a wireless operating licence and will have the full 50 km range (although most uses will probably be around 6-10 km). However, those at 2.4 or 5 GHz do not require a licence in most regulatory jurisdictions, because these frequency bands allow unlicensed use. In these bands, WiMAX operates at a much lower wireless power and has a very limited range (roughly the same as for WLAN, which also uses these frequency bands).
Deregulation
A major driver impacting the broadband wireless explosion is the advent of global telecom deregulation, opening up the telecommunications/ Internet access industries to a host of new players. As more and more countries enable carriers and service providers to operate in a variety of frequencies, new and lucrative broadband access markets are springing up everywhere.
Wireless technology requires the use of frequencies contained within a given spectrum to transfer voice and data. Governments allocate a specific range of that spectrum to incumbent and competitive carriers, as well as cellular operators, ISPs and other service providers, enabling them to launch a variety of broadband initiatives based exclusively on wireless networking solutions. There are two main types of spectrum allocation: licensed and unlicensed.
68
WiMAX IN DEPTH
MMDS
-2500-2690
2700-2900
3.5GHz band 3400-3600
Low/Mid
UNII-band
(802.11a)
5150-5350
Upper
UNII-band
-5725-5850
3300-3400
ISM (11 big)
2400-2480
WRC (new) 5470-5725
US WCS 2305-2320 2345-2360
I I WiMAX profiles available Future WiMAX profiles Č WIFI
Figure 2.14 WiMAX spectrum
• Licensed frequencies are typically awarded through an auction or contest to those who present the soundest business plans to the regulatory authorities overseeing the process.
• Unlicensed frequencies allow multiple service providers to utilize the same section of the spectrum and compete with each other for customers.
Recent examples of the global spread of bandwidth allocations/ licences that are available to wireless operators as a result of deregulation include: Italy - 26 and 28 GHz bands; UK - 2.4, 3.5, 10.5 and 28 GHz bands; France - 2.4, 3.5 and 26 GHz bands; Sweden - 3.5 GHz band; EC - 5.4 GHz, to be made available for carriers throughout continental Europe; China - 2.4, 3.5, 5.8 and 26 GHz bands; and Brazil - 3.5 and 10.5 GHz bands (Figure 2.14).
Spectrum: Licensed and Unlicensed
Licensed spectrum requires an authorization/license from the regulators, which offers that individual user - or ‘licensee’ - the exclusive rights to operate on a specific frequency (or frequencies) at a particular location or within a defined geographic area. In contrast, unlicensed spectrum permits any user to access specific frequencies within a specified geographic area without prior regulatory authorization.
While users of this spectrum do not have to apply for individual licences or pay to use the spectrum, they are still subject to certain rules.
WiMAX ROLLOUT 69
Table 2.9 List of first-stage system profiles used for WiMAX certification
Configuration Profile name
3.5 GHz TDD 7 MHz 3.5T1
3.5 GHz TDD 3.5 MHz 3.5T2
3.5 GHz FDD 3.5 MHz 3.5F1
3.5 GHz FDD 7 MHz 3.5F2
5.8 GHz TDD 10 MHz 5.8T
First, unlicensed users must not cause interference to licensed users and must accept any interference they receive. Second, any equipment that will be utilized on unlicensed spectrum must be approved in advance by the regulators (Table 2.9).
2.9 WiMAX ROLL-OUT
WiMAX Forum anticipates roll-out of its technology in three phases. Phase I (Present-2005)
Fixed Location, Private Line Services, Hotspot Backhaul
Using the initial 802.16 standard as its cornerstone, phase I of WiMAX deployment has already begun with the provision of traditional dedicated-line services to carriers and enterprises. Phase I also includes such operations as aggregating public WiFi hotspots to a central, high-capacity Internet connection.
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