Sec.  78.105   Antenna systems.

   (a) For fixed stations operating in the 12.7–13.2 GHz and 17.7–19.7 GHz
   bands, the following standards apply:

   (1)  Fixed  CARS stations shall use directional antennas that meet the
   performance standards indicated in the following table.

   (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) 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.

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

   (A) With either the maximum beamwidth 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 beamwidith 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 °
   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 beamwidth 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 defined in
   paragraph (a) of this section.

   (4) Pickup stations are not subject to the performance standards herein
   stated.  The  provisions  of  this paragraph are effective for all new
   applications accepted for filing after October 1, 1981.

   (b) Any fixed station licensed pursuant to an application accepted for
   filing prior to October 1, 1981, may continue to use its existing antenna
   system, subject to periodic renewal until April 1, 1992, After April 1,
   1992, all licensees 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 CAR service or TV auxiliary
   broadcast, which shares the 12.7–13.20 GHz band with CARS, 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 require conversion 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  Sec. 78.18a was accomplished.

   [ 45 FR 78694 , Nov. 26, 1980, as amended at  49 FR 37779 , Sept. 26, 1984;  50 FR 7343 , Feb. 22, 1985;  51 FR 19841 , June 3, 1986;  56 FR 50664 , Oct. 8,
   1991;  62 FR 4923 , Feb. 3, 1997;  68 FR 12776 , Mar. 17, 2003]