ITU launched the
program of International Mobile Telecommunications in 2000 (IMT-2000) for third
generation (3G) wireless networks defined by a set of independent ITU
Recommendations. In 2006 IEEE proposed to ITU to include WiMax in IMT-2000 as
IP-OFDMA, based on IEEE 802.16-2004, IEEE 802.16e-2005 and Release 1.0 of the
WiMax Forum. ITU approved of that addition in 2007. Later on , the IEEE
802.16-2009 and WiMax Forum Release 1.5 were used for more up to date features
(for example, the frequency division duplexing). ITU published a new version,
the IMT Advanced in 2007, where the WiMax standard was again included and in
December 2010 WiMax was regarded as a fourth generation (4G) technology by the
ITU (along with Long Term Evolution-LTE and High Speed Packet Access
Plus-HSPA+) [19].
Even though at the
first glance the ITU standardization may not occur to have obvious advantages,
the truth is far from this. The standardization itself can be conducted by the
IEEE and the WiMax Forum, but the recognition from the ITU added international
credibility and global reputation, at the same level with HSPA and Code
Division Multiple Access (CDMA) . Furthermore, part of the spectrum (especially
around the 2.5 GHz) allocated for the IMT-2000 technologies can now be used by
WiMax, as it belongs to them [7].
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