§  25.209   Antenna performance standards.

   (a) The gain of any antenna to be employed in transmission from an
   earth station in the fixed-satellite service shall lie below the
   envelope defined below:

   (1) In the plane of the geostationary satellite orbit as it appears at
   the particular earth station location, for earth stations not operating
   in the Ka-band or conventional Ku-band:
   29-25log[10]TH dBi For 1.5DEG <= TH <= 7DEG
   8              dBi For 7DEG < TH <= 9.2DEG
   32-25log[10]TH dBi For 9.2DEG < TH <= 48DEG
   -10            dBi For 48DEG < TH <= 180DEG

   where TH is the angle in degrees from the axis of the main lobe, and
   dBi refers to dB relative to an isotropic radiator. For the purposes of
   this section, the peak gain of an individual sidelobe may not exceed
   the envelope defined above for TH between 1.5 and 7.0 degrees. For TH
   greater than 7.0 degrees, the envelope may be exceeded by no more than
   10% of the sidelobes, provided no individual sidelobe exceeds the gain
   envelope given above by more than 3 dB.

   (2) In the plane of the geostationary satellite orbit as it appears at
   the particular earth station location, for earth stations operating in
   the Ka-band or conventional Ku-band:
   29-25log[10]TH dBi For 1.5DEG <= TH <= 7DEG
   8              dBi For 7DEG < TH <= 9.2DEG
   32-25log[10]TH dBi For 9.2DEG < TH <= 48DEG
   -10            dBi For 48DEG < TH <= 85DEG
   0              dBi For 85DEG < TH <= 180DEG

   (3) In all other directions, or in the plane of the horizon including
   any out-of-plane potential terrestrial interference paths, for all
   earth stations not operating in the Ka-band or conventional Ku-band:

   Outside the main beam, the gain of the antenna shall lie below the
   envelope defined by:
   32-25log[10]TH dBi For 3DEG < TH <= 48DEG
   -10            dBi For 48DEG < TH <= 180DEG

   where TH and dBi are defined above. For the purposes of this section,
   the envelope may be exceeded by no more than 10% of the sidelobes
   provided no individual sidelobe exceeds the gain envelope given above
   by more than 6 dB. The region of the main reflector spillover energy is
   to be interpreted as a single lobe and shall not exceed the envelope by
   more than 6 dB.

   (4) In all other directions, or in the plane of the horizon including
   any out-of-plane potential terrestrial interference paths, for all
   earth stations operating in the Ka-band or conventional Ku-band:

   Outside the main beam, the gain of the antenna shall lie below the
   envelope defined by:
   32-25log[10]TH dBi For 3DEG < TH <= 48DEG
   -10            dBi For 48DEG < TH <= 85DEG
   0              dBi For 85DEG < TH <= 180DEG

   where TH and dBi are defined above. For the purposes of this section,
   the envelope may be exceeded by no more than 10% of the sidelobes
   provided no individual sidelobe exceeds the gain envelope given above
   by more than 6 dB. The region of the main reflector spillover energy is
   to be interpreted as a single lobe and shall not exceed the envelope by
   more than 6 dB.

   (5) Elliptical earth station antennas may be operated only when the
   major axis of the antenna is aligned with the plane of the
   geostationary satellite orbit as it appears at the particular earth
   station location.

   (b) The off-axis cross-polarization gain of any antenna to be employed
   in transmission from an earth station to a space station in the
   domestic fixed-satellite service shall be defined as follows:

   (1) In the plane of the geostationary satellite orbit as it appears at
   the particular earth station location:
   19-25log[10]TH dBi For 1.8DEG < TH <= 7DEG
   -2             dBi For 7DEG < TH <= 9.2DEG

   where TH is the angle in degrees from the axis of the main lobe, and
   dBi refers to dB relative to an isotropic radiator.

   (2) In all other directions, or in the plane of the horizon including
   any out-of-plane potential terrestrial interference paths:
   19-25log[10]TH dBi For 3DEG < TH <= 7DEG
   -2             dBi For 7DEG < TH <= 9.2DEG

   where TH and dBi are defined above.

   (c)(1) Earth station antennas licensed for reception of radio
   transmissions from a space station in the fixed-satellite service are
   protected from radio interference caused by other space stations only
   to the degree to which harmful interference would not be expected to be
   caused to an earth station employing an antenna conforming to the
   referenced patterns defined in paragraphs (a) and

   (b) of this section, and protected from radio interference caused by
   terrestrial radio transmitters identified by the frequency coordination
   process only to the degree to which harmful interference would not be
   expected to be caused to an earth station conforming to the reference
   pattern defined in paragraphs (a)(3) and (a)(4) of this section.

   (2) 17/24 GHz BSS telemetry earth stations are protected from harmful
   interference caused by other space stations to the extent set forth in
   paragraph (c)(1) of this section. Receive-only earth stations in the
   17/24 GHz BSS are protected from harmful interference caused by other
   space stations to the extent set forth in § 25.224 of this part.

   (d) The patterns specified in paragraphs (a) and (b) of this section
   shall apply to all new earth station antennas initially authorized
   after February 15, 1985 and shall apply to all earth station antennas
   after March 11, 1994.

   (e) The operations of any earth station with an antenna not conforming
   to the standards of paragraphs (a) and (b) of this section shall impose
   no limitations upon the operation, location or design of any
   terrestrial station, any other earth station, or any space station
   beyond those limitations that would be expected to be imposed by an
   earth station employing an antenna conforming to the reference patterns
   defined in paragraphs (a) and (b) of this section.

   (f) An earth station with an antenna not conforming to the standards of
   paragraphs (a) and (b) of this section will be authorized only if the
   applicant meets its burden of demonstrating that its antenna will not
   cause unacceptable interference. For ESVs in the C-band, this
   demonstration must comply with the procedures set forth in § 25.221.
   For ESVs in the Ku-band, this demonstration must comply with the
   procedures set forth in § 25.222. For VMES, this demonstration shall
   comply with the procedures set forth in § 25.226. For feeder-link earth
   stations in the 17/24 GHz BSS, this demonstration must comply with the
   procedures set forth in § 25.223. For other FSS earth stations, this
   demonstration must comply with the procedures set forth in § § 25.218
   or 25.220. In any case, the Commission will impose appropriate terms
   and conditions in its authorization of such facilities and operations.

   (g) The antenna performance standards of small antennas operating in
   the 12/14 GHz band with diameters as small as 1.2 meters starts at
   1.25DEG instead of 1DEG as stipulated in paragraph (a) of this section.

   (h)(1) The gain of any antennas to be employed in transmission from a
   gateway earth station antenna operating in the frequency bands
   10.7-11.7 GHz, 12.75-13.15 GHz, 13.2125-13.25 GHz, 13.8-14.0 GHz, and
   14.4-14.5 GHz and communicating with NGSO FSS satellites shall lie
   below the envelope defined as follows:

   29 - 25log[10](TH) dBi - 10 dBi

   1^B <= TH <= 36^B

   36^B <= TH <= 180^B

   Where: TH is the angle in degrees from the axis of the main lobe, and
   dBi refers to dB relative to an isotropic radiator.

   (2) For the purposes of this section, the peak gain of an individual
   sidelobe may not exceed the envelope defined in paragraph (h)(1) of
   this section.

   [ 48 FR 40255 , Sept. 6, 1983, as amended at  50 FR 2675 , Jan. 18, 1985;
    50 FR 39004 , Sept. 26, 1985;  58 FR 13420 , Mar. 11, 1993;  66 FR 10630 ,
   Feb. 16, 2001;  70 FR 32255 , June 2, 2005;  72 FR 50029 , Aug. 29, 2007;
    73 FR 70901 , Nov. 24, 2008;  74 FR 57099 , Nov. 4, 2009]