§ 74.641   Antenna systems.

   (a) For fixed stations operating above 2025 MHz, the following standards
   apply:

   (1) Fixed TV broadcast auxiliary stations shall use directional antennas
   that meet the performance standards indicated in the following table. Upon
   adequate showing of need to serve a larger sector, or more than a single
   sector, greater beamwidth or multiple antennas may be authorized. Applicants
   shall request, and authorization for stations in this service will specify,
   the polarization of each transmitted signal. Booster station antennas having
   narrower  beamwidths and reduced sidelobe radiation may be required in
   congested areas, or to resolve interference problems.

   (i) Stations must employ an antenna that meets the performance standards for
   Category  B.  In areas subject to frequency congestion, where proposed
   facilities would be precluded by continued use of a Category B antenna, a
   Category A antenna must be employed. The Commission may require the use of a
   high performance antenna where interference problems can be resolved by the
   use of such antennas.

   (ii) Licensees shall comply with the antenna standards table shown in this
   paragraph in the following manner:

   (A) With either the maximum beamwith to 3 dB points requirement or with the
   minimum antenna gain requirement; and

   (B) With the minimum radiation suppression to angle requirement.

   Antenna Standards
   Frequency (MHz) Category Maximum beamwidth to 3 dB points^1 (included angle
   in degrees) Minimum antenna gain (dbi) Minimum radiation suppression to
   angle in degrees from centerline of main beam in decibels
   5° to 10° 10° to 15° 15° to 20° 20° to 30° 30° to 100° 100° to 140° 140° to
   180°
   1,990 to 2,110 A
   B 5.0
   8.0 n/a
   n/a 12
   5 18
   18 22
   20 25
   20 29
   25 33
   28 39
   36
   6,875 to 7,125 A
   B 1.5
   2.0 n/a
   n/a 26
   21 29
   25 32
   29 34
   32 38
   35 41
   39 49
   45
   12,700 to 13,250 A
   B 1.0
   2.0 n/a
   n/a 23
   20 28
   25 35
   28 39
   30 41
   32 42
   37 50
   47
   17,700 to 19,700 A
   B 2.2
   2.2 38
   38 25
   20 29
   24 33
   28 36
   32 42
   35 55
   36 55
   36

   ^1If a licensee chooses to show compliance using maximum beamwith to 3 dB
   points,  the  beamwidth  limit shall apply in both the azimuth and the
   elevation planes.

   (2) New periscope antenna systems will be authorized upon a certification
   that the radiation, in a horizontal plane, from an illuminating antenna and
   reflector  combination  meets or exceeds the antenna standards of this
   section. This provision similarly applies to passive repeaters employed to
   redirect or repeat the signal from a station's directional antenna system.

   (3)  The choice of receiving antennas is left to the discretion of the
   licensee. However, licensees will not be protected from interference which
   results from the use of antennas with poorer performance than identified in
   the table of this section.

   (4) [Reserved]

   (5) Pickup stations are not subject to the performance standards herein
   stated.

   (b) All fixed stations are to use antenna systems in conformance with the
   standards of this section. TV auxiliary broadcast stations are considered to
   be located in an area subject to frequency congestion and must employ a
   Category A antenna when:

   (1) A showing by an applicant of a new TV auxiliary broadcast station or
   Cable Television Relay Service (CARS) station, which shares the 12.7-13.20
   GHz band with TV auxiliary broadcast, indicates that use of a category B
   antenna limits a proposed project because of interference, and

   (2) That use of a category A antenna will remedy the interference thus
   allowing the project to be realized.

   (c) As an exception to the provisions of this section, the FCC may approve
   requests for use of periscope antenna systems where a persuasive showing is
   made that no frequency conflicts exist in the area of proposed use. Such
   approvals  shall  be  conditioned to a standard antenna as required in
   paragraph  (a) of this section when an applicant of a new TV auxiliary
   broadcast or Cable Television Relay station indicates that the use of the
   existing antenna system will cause interference and the use of a category A
   or B antenna will remedy the interference.

   (d)  As  a further exception to the provision of paragraph (a) of this
   section, the Commission may approve antenna systems not conforming to the
   technical standards where a persuasive showing is made that:

   (1)  Indicates  in  detail  why  an  antenna system complying with the
   requirements of paragraph (a) of this section cannot be installed, and

   (2) Includes a statement indicating that frequency coordination as required
   in § 74.604 (a) was accomplished.

   [ 45 FR 78693 , Nov. 26, 1980, as amended at  49 FR 7131 , Feb. 27, 1984;  49 FR 37778 , Sept. 26, 1984;  50 FR 7342 , Feb. 22, 1985;  51 FR 19840 , June 3, 1986;
    52 FR 7143 , Mar. 9, 1987;  55 FR 11587 , Mar. 29, 1990;  56 FR 50663 , Oct. 8,
   1991;  62 FR 4922 , Feb. 3, 1997;  68 FR 12771 , Mar. 17, 2003]

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