AUDIO VIDEO NEWS

As the DTV transition looms in February 2009, some TV stations are worrying that their signal dispersion pattern may shrink or change shape. To deal with that potential problem, the Federal Communications Commission has green-lighted distributed transmission systems (DTS). This is essentially a fix that would allow the usual single broadcast tower to be supplemented with additional transmitters.

The problem--as the FCC discovered during a dress rehearsal of the DTV transition in Wilmington, Carolina--is that digital TV signals propagate differently than analog TV signals. As a result, some stations changed their contours and lost range, and this became apparent even to viewers who had retrofitted their antenna-dependent analog TVs with set-top converters.

DTS (no relation to the surround standard setting outfit) will allow stations to add transmitters to fill out their contours with digital signals and hold onto the viewers currently served by analog signals. To do this, they will have to apply for a waiver, and adding the extra transmitters will take some time. So this process may continue working itself out long after the transition deadline in February.

See FCC order (PDF).