AT&T doesn't own the licenses to the spectrum yet, but it has indicated that it has struck deals to acquire the rights from the current license holders.
"AT&T took real risks to develop this under-utilized band and is committed to devoting the resources necessary to unlock its full potential," Joan Marsh, an AT&T vice president, said in a statement. "We expect to commence deployment of LTE infrastructure in the band in as early as three years, allowing us to enhance our wireless broadband services."
The FCC said the order is part of its effort to free up more spectrum for mobile broadband. Mobile carriers have struggled in recent years to keep pace with the skyrocketing demands placed on their networks by data-hungry smartphones and tablet computers.