In 2011, WiMAX subscribers worldwide may reach 14.9 million, but the winner of the 4G race will be LTE by a country mile, predicts iSuppli. LTE subs were virtually zero in 2009, iSuppli says, with the first LTE service available by Telenora in Sweden. MetroPCS was the first in the US with LTE service in Las Vegas and Dallas. Verizon was next to implement LTE in the U.S. It launched in December in 38 cities using the new 700-MHz spectrum. AT&T won’t launch LTE until sometime later in 2011. 
An estimated 10 LTE operators worldwide have launched to date, and more than 30 new operators will start LTE services this year. For WiMAX, the majority of operators are in Europe, followed by the Asia-Pacific region, the Middle East and Africa, and then the Americas.
Both LTE and WiMAX are based on orthogonal frequency-division multiple access (OFDMA) technology in wide 5-, 10-, and 20-MHz channels. They are strictly IP-based (Internet Protcol) or packet-based, unlike the current circuit switched technologies of the existing cellular network. 
Spectral efficiency is typically measured in bits/Hz. LTE and WiMAX have about twice the bits per hertz of earlier 3G systems. Posted by Sam Churchill on Monday, April 4th, 2011 at 3:07 pm.
