Broadcast auxiliary service

These are essentially internal-use backhaul channels not intended for actual reception by the public, but part of the airchain required to get those signals back to the broadcast studio from the field.

In North America, DVB-T, precisely the same modulation technique as European Broadcast, is used, using a constellation of QPSK, 16QAM, or 64QAM, enabling sufficient digital bandwidths at 6 MHz deviation for transmission of an MPEG transport stream at 10 or more megabits per second, producing three "lower", "center", and "upper" overlapping 6 MHz channels within each 12 MHz channel.

In the United States between 2005 and 2010, the Federal Communications Commission (FCC) moved TV channels in the 2 GHz TV BAS band at the request of Sprint Nextel, so that it could use a portion which was adjacent to PCS frequencies it already uses.

After multiple extensions granted by the FCC, it was finally done in July 2010, with the completion of the Anchorage, Alaska TV market.

The cleared band is now used for PCS, AWS, and MSS services, including mobile broadband.