§ 15.712   Interference protection requirements.

   (a) Digital television stations, and digital and analog Class A TV, low
   power TV, TV translator and TV booster stations:

   (1) Protected contour. TVBDs must protect digital and analog TV
   services within the contours shown in the following table. These
   contours are calculated using the methodology in § 73.684 of this
   chapter and the R-6602 curves contained in § 73.699 of this chapter.
   Type of station Protected contour
   Channel Contour
   (dBu) Propagation
   curve
   Analog: Class A TV, LPTV, translator and booster Low VHF (2-6) 47
   F(50,50)
       High VHF (7-13) 56 F(50,50)
       UHF (14-69) 64 F(50,50)
   Digital: Full service TV, Class A TV, LPTV, translator and booster Low
   VHF (2-6) 28 F(50,90)
       High VHF (7-13) 36 F(50,90)
       UHF (14-51) 41 F(50,90)

   (2) Required separation distance. TVBDs must be located outside the
   contours indicated in paragraph (a)(1) of this section of co-channel
   and adjacent channel stations by at least the minimum distances
   specified in the following table. Personal/portable TVBDs operating in
   Mode II must comply with the separation distances specified for an
   unlicensed device with an antenna height of less than 3 meters.
   Alternatively, Mode II personal/portable TVBDs may operate at closer
   separation distances from the contour of adjacent channel stations than
   this table permits, including inside the contour of adjacent channel
   stations, provided the power level is reduced to 40 mW or less as
   specified in § 15.709(a)(2).
   Antenna height above average terrain of unlicensed device Required
   separation (km) from digital or analog TV (full service or low power)
   protected contour
   Co-channel
   (km) Adjacent
   channel
   (km)
   Less than 3 meters 4.0 0.4
   3-Less than 10 meters 7.3 0.7
   10-Less than 30 meters 11.1 1.2
   30-Less than 50 meters 14.3 1.8
   50-Less than 75 meters 18.0 2.0
   75-Less than 100 meters 21.1 2.1
   100-Less than 150 meters 25.3 2.2
   150-Less than 200 meters 28.5 2.3
   200-250 meters 31.2 2.4

   (3) The antenna height above ground for a fixed TVBD may not exceed 30
   meters.

   (b) TV translator, Low Power TV (including Class A) and Multi-channel
   Video Programming Distributor (MVPD) receive sites. MVPD, TV translator
   station and low power TV (including Class A) station receive sites
   located outside the protected contour of the TV station(s) being
   received may be registered in the TV bands database if they are no
   farther than 80 km outside the nearest edge of the relevant contour(s).
   Only channels received over the air and used by the MVPD, TV translator
   station or low power/Class A TV station may be registered. TVBDs may
   not operate within an arc of +-/ -30 degrees from a line between a
   registered receive site and the contour of the TV station being
   received in the direction of the station's transmitter at a distance of
   up to 80 km from the edge of the protected contour of the received TV
   station for co-channel operation and up to 20 km from the registered
   receive site for adjacent channel operation, except that the protection
   distance shall not exceed the distance from the receive site to the
   protected contour. Outside of this +-/ -30 degree arc, TVBDs may not
   operate within 8 km from the receive site for co-channel operation and
   2 km from the receive site for adjacent channel operation. For purposes
   of this section, a TV station being received may include a full power
   TV station, TV translator station or low power TV/Class A TV station.

   (c) Fixed Broadcast Auxiliary Service (BAS) Links. For permanent BAS
   receive sites appearing in the Commission's Universal Licensing System
   or temporary BAS receive sites registered in the TV bands database,
   TVBDs may not operate within an arc of +-30 degrees from a line between
   the BAS receive site and its associated permanent transmitter within a
   distance of 80 km from the receive site for co-channel operation and 20
   km for adjacent channel operation. Outside this +-30 degree arc, TVBDs
   may not operate within 8 km from the receive site for co-channel
   operation and 2 km from the receive site for adjacent channel
   operation.

   (d) PLMRS/CMRS operations: TVBDs may not operate at distances less than
   134 km for co-channel operations and 131 km for adjacent channel
   operations from the coordinates of the metropolitan areas and on the
   channels listed in § 90.303(a) of this chapter. For PLMRS/CMRS
   operations authorized by waiver outside of the metropolitan areas
   listed in § 90.303(a) of this chapter, co-channel and adjacent channel
   TVBDs may not operate closer than 54 km and 51 km, respectively from a
   base station.

   (e) Offshore Radiotelephone Service. TVBDs may not operate on channels
   used by the Offshore Radio Service within the geographic areas
   specified in § 74.709(e) of this chapter.

   (f) Low power auxiliary services, including wireless microphones: (1)
   Fixed TVBDs are not permitted to operate within 1 km, and
   personal/portable TVBDs will not be permitted to operate within 400
   meters, of the coordinates of registered low power auxiliary station
   sites on the registered channels during the designated times they are
   used by low power auxiliary stations.

   (2) TVBDs are not permitted to operate on the first channel on each
   side of TV channel 37 (608-614 MHz) that is not occupied by a licensed
   service.

   (g) Border areas near Canada and Mexico: Fixed and personal/portable
   TVBDs shall comply with the required separation distances in
   § 15.712(a)(2) from the protected contours of TV stations in Canada and
   Mexico. TVBDs are not required to comply with these separation
   distances from portions of the protected contours of Canadian or
   Mexican TV stations that fall within the United States.

   (h) Radio astronomy services: Operation of fixed and personal/portable
   TVBDs is prohibited on all channels within 2.4 kilometers at the
   following locations.

   (1) The Naval Radio Research Observatory in Sugar Grove, West Virginia
   at 38 30 58 N and 79 16 48 W.

   (2) The Table Mountain Radio Receiving Zone (TMRZ) at 40 08 02 N and
   105 14 40 W.

   (3) The following facilities:
   Observatory Latitude
   (deg/min/sec) Longitude
   (deg/min/sec)
   Allen Telescope Array 40 49 04 N 121 28 24 W
   Arecibo Observatory 18 20 37 N 066 45 11 W
   Green Bank Telescope (GBT) 38 25 59 N 079 50 23 W
   Very Large Array (VLA) Rectangle between latitudes 33 58 22 N and 34 14
   56 N, and longitudes 107 24 40 W and 107 48 22 W
   Very Long Baseline Array (VLBA) Stations:
   Pie Town, NM 34 18 04 N 108 07 09 W
   Kitt Peak, AZ 31 57 23 N 111 36 45 W
   Los Alamos, NM 35 46 30 N 106 14 44 W
   Ft. Davis, TX 30 38 06 N 103 56 41 W
   N. Liberty, IA 41 46 17 N 091 34 27 W
   Brewster, WA 48 07 52 N 119 41 00 W
   Owens Valley, CA 37 13 54 N 118 16 37 W
   St. Croix, VI 17 45 24 N 064 35 01 W
   Hancock, NH 42 56 01 N 071 59 12 W
   Mauna Kea, HI 19 48 05 N 155 27 20 W

   [ 74 FR 7326 , Feb. 17, 2009, as amended at  75 FR 75839 , Dec. 6, 2010;  77 FR 29246 , May 17, 2012]

   return arrow Back to Top