FCC Proposes Rules for Distributed Transmission Systems

The FCC issued a Clarification Order and Notice of Proposed Rulemaking (Docket 05-312) clarifying the interim rules for distributed transmission systems (DTS) and initiating a rule making regarding future use of DTS by broadcasters.

The Clarification Order cautioned stations designing DTS facilities that DTS service beyond the area it certified it would serve on FCC Form 381 "may be considered secondary and unprotected in the planning for post-transition DTV service, and therefore may not be allowed to continue past the end of the transition unless specifically reauthorized." The criteria are the same as for single transmitter stations--new interference to other stations exceeding 0.1 percent is not allowed. For stations using DTS, the interference is based on the strongest of the multiple DTS signals and not the combined effect of multiple DTS transmitters.

Stations proposing to use DTS were also notified the FCC would "examine whether every location in a station's replication service area is within the PNLC [Predicted Noise-Limited Contour] of at least one proposed DTS transmitter" to verify that the DTS was providing service over all of a station's replication service area.

In my December RF Technology column, I discuss some of the FCC rules proposed for future DTS use. For more information on these rules and also proposed rules for low power TV and Class A TV use of DTS, see the FCC news release FCC Initiates Rulemaking on Distributed Transmission Technology for Digital TV Stations and the complete Clarification Order and Notice of Proposed Rulemaking (Docket 05-312).