§ 25.218   Off-axis EIRP density envelopes for FSS earth stations transmitting
in certain frequency bands.

   (a) This section applies to all applications for Fixed-Satellite Service
   earth stations transmitting to geostationary space stations in the C band,
   Ku band, or extended Ku band, except for:

   (1) ESV, VMES, and ESAA applications, and

   (2) Analog video earth station applications.

   (b) Earth station applications subject to this section are eligible for
   routine  processing  if they meet the applicable off-axis EIRP density
   envelope set forth in this section below. The terms “conventional Ku band”
   and “extended Ku band are defined in § 25.103.

   (c)  C-band  analog  earth station operations. (1) In the plane of the
   geostationary satellite orbit as it appears at the particular earth station
   location:
   29.5-25log10θ dBW/4 kHz For 1.5�° ≤θ ≤7�°
   8.5           dBW/4 kHz For 7�° <θ ≤9.2�°
   32.5-25log10θ dBW/4 kHz For 9.2�° <θ ≤48�°
   −9.5          dBW/4 kHz For 48�° <θ ≤180�°

   where θ is the angle in degrees from the line connecting the focal point of
   the antenna to the target satellite, and the geostationary orbit plane is
   determined by the focal point of the antenna and the line tangent to the arc
   of  the  geostationary  satellite  orbit at the position of the target
   satellite. For the purposes of this section, the peak EIRP density of an
   individual sidelobe may not exceed the envelope defined above for θ between
   1.5�° and 7.0�°. For θ greater than 7.0�°, the envelope may be exceeded by no
   more than 10% of the sidelobes, provided no individual sidelobe exceeds the
   envelope given above by more than 3 dB.

   (2) In all other directions, or in the plane of the horizon including any
   out-of-plane potential terrestrial interference paths:
   32.5-25log10θ dBW/4 kHz For 3�° ≤θ ≤48�°
   −9.5          dBW/4 kHz For 48�° <θ ≤180�°

   where θ is the angle in degrees from the line connecting the focal point of
   the antenna to the target satellite, within any plane that includes that
   line, with the exception of the plane determined by the focal point of the
   antenna and the line tangent to the arc of the geostationary satellite orbit
   at the position of the target satellite. 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 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.

   (d)  C-band  digital earth station operations. (1) In the plane of the
   geostationary satellite orbit as it appears at the particular earth station
   location:
   26.3-10log10(N)-25log10θ  dBW/4 kHz For 1.5�° ≤θ ≤7�°
   5.3-10log10(N)            dBW/4 kHz For 7�° <θ ≤9.2�°
   29.3 −10log10(N)−25log10θ dBW/4 kHz For 9.2�° <θ ≤48�°
   −12.7-10log10(N)          dBW/4 kHz For 48�° <θ ≤180�°

   where θ and the plane of the geostationary satellite orbit are defined in
   paragraph (c)(1) of this section, and N is defined below. For the purposes
   of this section, the peak EIRP density of an individual sidelobe may not
   exceed the envelope defined above for θ between 1.5�° and 7.0�°. For θ greater
   than  7.0�°,  the  envelope  may be exceeded by no more than 10% of the
   sidelobes, provided no individual sidelobe exceeds the envelope given above
   by more than 3 dB. For digital SCPC using frequency division multiple access
   (FDMA) or time division multiple access (TDMA) technique, N is equal to one.
   For digital SCPC using code division multiple access (CDMA) technique, N is
   the  maximum  number of co-frequency simultaneously transmitting earth
   stations in the same satellite receiving beam.

   (2) In all other directions, or in the plane of the horizon including any
   out-of-plane potential terrestrial interference paths:
   29.3-10log10(N)-25log10θ dBW/4 kHz For 3�° ≤θ ≤48�°
   −12.7-10log10(N)         dBW/4 kHz For 48�° <θ ≤180�°

   where θ is defined in paragraph (c)(2) of this section, and N is defined in
   paragraph (d)(1) of this section. 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 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.

   (e) Conventional Ku-band analog earth station operations. (1) In the plane
   of the geostationary satellite orbit as it appears at the particular earth
   station location:
   21-25log10θ dBW/4 kHz For 1.5�° ≤θ ≤7�°
   0           dBW/4 kHz For 7�° <θ ≤9.2�°
   24-25log10θ dBW/4 kHz For 9.2�° <θ ≤48�°
   −18         dBW/4 kHz For 48�° <θ ≤85�°
   −8          dBW/4 kHz For 85�° <θ ≤180�°

   where  θ  and  the plane of the geostationary satellite are defined in
   paragraph (c)(1) of this section. For the purposes of this section, the peak
   EIRP density of an individual sidelobe may not exceed the envelope defined
   above for θ between 1.5�° and 7.0�°. For θ greater than 7.0�°, the envelope may
   be exceeded by no more than 10% of the sidelobes, provided no individual
   sidelobe exceeds the envelope given above by more than 3 dB.

   (2) In all other directions, or in the plane of the horizon including any
   out-of-plane potential terrestrial interference paths:
   24-25log10θ dBW/4 kHz For 3�° ≤θ ≤48�°
   −18         dBW/4 kHz For 48�° <θ ≤85�°
   −8          dBW/4 kHz For 85�° <θ ≤180�°

   where θ is defined in paragraph (c)(2) of this section. 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 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.

   (f) Conventional Ku-band digital earth station operations. (1) In the plane
   of the geostationary satellite orbit as it appears at the particular earth
   station location:
   15-10log10(N)-25log10θ dBW/4 kHz For 1.5�° ≤θ ≤7�°
   −6-10log10(N)          dBW/4 kHz For 7�° <θ ≤9.2�°
   18-10log10(N)-25log10θ dBW/4 kHz For 9.2�° <θ ≤48�°
   −24-10log10(N)         dBW/4 kHz For 48�° <θ ≤85�°
   −14-10log10(N)         dBW/4 kHz For 85�° <θ ≤180�°

   where θ and the plane of the geostationary satellite orbit are defined in
   paragraph (c)(1) of this section, and N is defined below. For the purposes
   of this section, the peak EIRP density of an individual sidelobe may not
   exceed the envelope defined above for θ between 1.5�° and 7.0�°. For θ greater
   than  7.0�°,  the  envelope  may be exceeded by no more than 10% of the
   sidelobes, provided no individual sidelobe exceeds the envelope given above
   by more than 3 dB. For digital SCPC using frequency division multiple access
   (FDMA) or time division multiple access (TDMA) technique, N is equal to one.
   For digital SCPC using code division multiple access (CDMA) technique, N is
   the  maximum  number of co-frequency simultaneously transmitting earth
   stations in the same satellite receiving beam.

   (2) In all other directions, or in the plane of the horizon including any
   out-of-plane potential terrestrial interference paths:
   18-10log10(N)-25log10θ dBW/4 kHz For 3�° ≤θ ≤48�°
   −24-10log10(N)         dBW/4 kHz For 48�° <θ ≤85�°
   −14-10log10(N)         dBW/4 kHz For 85�° <θ ≤180�°

   where θ is defined in paragraph (c)(2) of this section, and N is defined in
   paragraph (f)(1) of this section. 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 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.

   (g) Extended Ku-band analog earth station operations. (1) In the plane of
   the geostationary satellite orbit as it appears at the particular earth
   station location:
   21-25log10θ dBW/4 kHz For 1.5�° ≤θ ≤7�°
   0           dBW/4 kHz For 7�° <θ ≤9.2�°
   24-25log10θ dBW/4 kHz For 9.2�° <θ ≤48�°
   −18         dBW/4 kHz For 48�° <θ ≤180�°

   where θ and the plane of the geostationary satellite orbit are defined in
   paragraph (c)(1) of this section. For the purposes of this section, the peak
   EIRP density of an individual sidelobe may not exceed the envelope defined
   above for θ between 1.5�° and 7.0�°. For θ greater than 7.0�°, the envelope may
   be exceeded by no more than 10% of the sidelobes, provided no individual
   sidelobe exceeds the envelope given above by more than 3 dB.

   (2) In all other directions, or in the plane of the horizon including any
   out-of-plane potential terrestrial interference paths:
   24-25log10θ dBW/4 kHz For 3�° ≤θ ≤48�°
   −18         dBW/4 kHz For 48�° <θ ≤180�°

   where θ is defined in paragraph (c)(2) of this section. 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 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.

   (h) Extended Ku-band digital earth station operations. (1) In the plane of
   the geostationary satellite orbit as it appears at the particular earth
   station location:
   15-10log10(N)-25log10θ dBW/4 kHz For 1.5�° ≤θ ≤7�°
   −6-10log10(N)          dBW/4 kHz For 7�° <θ ≤9.2�°
   18-10log10(N)-25log10θ dBW/4 kHz For 9.2�° <θ ≤48�°
   −24-10log10(N)         dBW/4 kHz For 48�° <θ ≤180�°

   where θ and the plane of the geostationary satellite orbit are defined in
   paragraph (c)(1) of this section, and N is defined below. For the purposes
   of this section, the peak EIRP density of an individual sidelobe may not
   exceed the envelope defined above for θ between 1.5�° and 7.0�°. For θ greater
   than  7.0�°,  the  envelope  may be exceeded by no more than 10% of the
   sidelobes, provided no individual sidelobe exceeds the envelope given above
   by more than 3 dB. For digital SCPC using frequency division multiple access
   (FDMA) or time division multiple access (TDMA) technique, N is equal to one.
   For digital SCPC using code division multiple access (CDMA) technique, N is
   the  maximum  number of co-frequency simultaneously transmitting earth
   stations in the same satellite receiving beam.

   (2) In all other directions, or in the plane of the horizon including any
   out-of-plane potential terrestrial interference paths:
   18-10log10(N)-25log10θ dBW/4 kHz For 3�° ≤θ ≤48�°
   −24-10log10(N)         dBW/4 kHz For 48�° <θ ≤85�°

   where θ is defined in paragraph (c)(2) of this section and N is defined in
   paragraph (h)(1) of this section. 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 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.

   [ 73 FR 70902 , Nov. 24, 2008, as amended at  74 FR 57099 , Nov. 4, 2009;  78 FR 8429 , Feb. 6, 2013;  78 FR 14927 , Mar. 8, 2013;  79 FR 8324 , Feb. 12, 2014]

   Effective Date Note: At  74 FR 9962 , Mar. 9, 2009, § 25.218, which contains
   information collection and recordkeeping requirements, became effective with
   approval by the Office of Management and Budget for a period of 3 years.

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