In U.S. broadcast law, a special temporary authorization or special temporary authority (STA) is a type of broadcast license which temporarily allows a broadcast station to operate outside of its normal technical or legal parameters. In the Federal Communications Commission (FCC) station database (CDBS), broadcast STA applications have a prefix of BSTA (general), BLSTA (legal), BESTA (engineering), or BLESTA (both). STAs can also be issued for other telecommunication services under FCC regulation.
Often an STA is necessary due to an unforeseen event. While one is no longer needed to replace a particular transmitter, it is necessary to replace a radio antenna with another one that has different characteristics. STAs are often issued for a particular mode of operation while a full application for a construction permit is pending. Station licensees must exhibit why the STA is necessary and serves the public good. For example, WANN-CD has a permit to use an omnidirectional antenna for digital TV, but received an STA to diplex into the same antenna used by analog WANN-LP, which has a slightly directional antenna. This obviously served the public good by getting the station on the air earlier (before the original full-power analog cutoff in June 2009), than waiting for the new antenna, even though coverage is somewhat less in some directions.
In some cases, an STA can allow a station to operate at low power, often to avoid losing its broadcast license after a year off-the-air. (The one-year limit was written into law by the U.S. Congress, without regard to extenuating circumstances any station might have, after it was determined that a large number of nominally licensed broadcast stations had remained off-the-air for years, preventing other applicants from using the frequency allocations.) For example, after WACS-TV was destroyed by a major tornado in March 2007, it had to get back on-air by March 2008, and was given an STA to take a broadcast translator off-air for more than 30 days, and another to use its transmitter on the main station's new tower and radio antenna until the new one was delivered. In another case, WYGA-CA 45 is operating on an STA at just one watt, until adjacent channel 46 ends its analog TV signal on 46.
Due to the inherently temporary nature of the DTV transition, numerous STAs have been issued for DTV stations. (These have prefixes BDSTA and BEDSTA.) WPSX-TV was issued several of these for the purpose of testing distributed transmission systems, when it was still in the experimental stage.
The FCC has also allowed AM stations to put broadcast translators on FM through STAs, although LPFM advocates often feel this is an abuse of process, and that there should instead be a rulemaking proceeding where formal objections can be raised.
An STA can also be used for special events as a Restricted Service Licence is in the U.K., however this is rare. During a state of disaster or other emergency, it is only necessary to file for an STA after the fact (but as soon as possible), if the change is due to the disaster (such as a destroyed antenna or radio tower), or to help the public cope with it by providing local emergency management information not available from other off-air or distant stations.