47 CFR 73.626 - DTV distributed transmission systems.
(a) A DTV station may be authorized to operate multiple synchronized transmitters on its assigned channel to provide service consistent with the requirements of this section. Such operation is called a distributed transmission system (DTS). Except as expressly provided in this section, DTV stations operating a DTS facility must comply with all rules applicable to DTV single-transmitter stations.
(b) For purposes of compliance with this section, a station's “authorized service area” is defined as the area within its predicted noise-limited service contour determined using the facilities authorized for the station in a license or construction permit for non-DTS, single-transmitter-location operation.
(c)Table of Distances. The following Table of Distances describes (by channel and zone) a station's maximum service area that can be obtained in applying for a DTS authorization.
(1) DTV station zones are defined in § 73.609.
(2)DTS reference point. A station's DTS reference point is established in the FCC Order that created or made final modifications to the Post-Transition DTV Table of Allotments, § 73.622(i), and the corresponding facilities for the station's channel assignment as set forth in that FCC Order.
(d)Determining DTS coverage. The coverage for each DTS transmitter is determined based on the F(50,90) field strength given in the Table of Distances (in paragraph (c) of this section), calculated in accordance with § 73.625(b). The combined coverage of a DTS station is the logical union of the coverage of all DTS transmitters.
(e)DTS protection from interference. A DTS station must be protected from interference in accordance with the criteria specified in § 73.616. To determine compliance with the interference protection requirements of § 73.616, the population served by a DTS station shall be the population within the station's combined coverage contour, excluding the population in areas that are outside both the DTV station's authorized service area and the Table of Distances area (in paragraph (c) of this section). Only population that is predicted to receive service by the method described in § 73.622(e)(2) from at least one individual DTS transmitter will be considered.
(f)Applications for DTS. An application proposing use of a DTS will not be accepted for filing unless it meets all of the following conditions:
(1) The combined coverage from all of the DTS transmitters covers all of the applicant's authorized service area;
(2) Each DTS transmitter's coverage is contained within either the DTV station's Table of Distances area (pursuant to paragraph (c) of this section) or its authorized service area, except where such extension of coverage beyond the station's authorized service area is of a minimal amount and necessary to meet the requirements of paragraph (f)(1) of this section;
(4) The coverage from one or more DTS transmitter(s) is shown to provide principal community coverage as required in § 73.625(a);
(5) The “combined field strength” of all the DTS transmitters in a network does not cause interference to another station in excess of the criteria specified in § 73.616, where the combined field strength level is determined by a “root-sum-square” calculation, in which the combined field strength level at a given location is equal to the square root of the sum of the squared field strengths from each transmitter in the DTS network at that location.
(6) Each DTS transmitter must be located within either the DTV station's Table of Distances area or its authorized service area.