The scarcity of spectrum is in some ways a question of timing, according to Stankey and others in the industry. Though carriers may have enough spectrum to build out their networks over the next few years, there is a need for urgent action to make more frequencies available because it can take 10 years or more to translate spectrum into services, said Charla Rath, vice president of policy development at Verizon Wireless, who spoke on a panel before the CTIA trade show on Monday.

For spectrum-rich Clearwire, the T-Mobile-AT&T deal is bad news in the short term because it momentarily satisfies the need for spectrum at two carriers who were in need of it, Marshall said. But the market for spectrum in the medium and long term is still strong, he said.

AT&T sees a need for more frequencies in the future to meet explosive growth in demand for mobile data over the coming years. The carrier's mobile data volume has grown 8,000 percent in the past four years, and the 2010 demand is expected to grow by eight to 10 times by 2015, according to AT&T Chairman and CEO Randall Stephenson.

"There's just going to be a constant need for additional spectrum," Stephenson said.

The IDG News Service