Sawanobori contended that spectrum owned by Verizon will have better propagation characteristics and will need fewer cell towers than Clearwire's. He claimed Verizon is also demonstrating LTE speeds of 5 to 12 Mbit/sec, compared to the 3-6 Mbit/sec performce of the Clearwire network.

Rinne said that AT&T will be able to use spectrum in the 700 MHz band, and then extend it to the 850 MHz and 1900 MHz bands in the future. "We will have the opportunity [to grow spectrum for] LTE in future years, both the quality and range of it," she said.

Both Verizon and AT&T said their LTE networks will support devices that have dual LTE-3G radios at first.

Verizon recently announced plans to launch an in 2011 while to announce the Supersonic device for its WiMax network next Tuesdat at the CTIA wireless show.

During the presentation, GSMA Alliance said that an Infonetics forecast predicts that LTE will be used on 41% of wireless devices in the U.S. in 2014. By comparison, HSPA will be used on 29% of wireless devices, EVDO on 27% and Wimax on 3%.