Sec.  25.210   Technical requirements for space stations in the Fixed-Satellite
Service.

   (a) All space stations in the Fixed-Satellite Service used for domestic
   service in the 3700–4200 MHz and 5925–6425 MHz frequency bands shall:

   (1) Use orthogonal linear polarization with one of the planes defined by the
   equatorial plane;

   (2) Be designed so that the polarization sense of uplink transmissions is
   opposite to that of downlink transmissions on the same transponder; and

   (3) Shall be capable of switching polarization sense upon ground command.

   (b) All space stations in the Fixed-Satellite Service in the 20/30 GHz band
   shall use either orthogonal linear or orthogonal circular polarization.
   Those space stations utilizing orthogonal linear polarization shall also
   comply with paragraph (a) of this section.

   (c) All space stations in the Fixed-Satellite Service shall have a minimum
   capability to change transponder saturation flux densities by ground command
   in 4 dB steps over a range of 12 dB.

   (d) All space stations in the Fixed Satellite Service in the 20/30 GHz band
   shall employ state-of-the-art full frequency reuse either through the use of
   orthogonal polarizations within the same beam and/or through the use of
   spatially independent beams.

   (e) [Reserved]

   (f) All space stations in the Fixed Satellite Service in the 3600–3700 MHz,
   3700–4200 MHz, 5091–5250 MHz, 5825–5925 MHz, 5925–6425 MHz, 6425–6525 MHz,
   6525–6700 MHz, 6700–7025 MHz, 10.7–10.95 GHz, 10.95–11.2 GHz, 11.2–11.45
   GHz, 11.45–11.7 GHz, 11.7–12.2 GHz, 12.2–12.7 GHz, 12.75–13.15 GHz,
   13.15–13.2125 GHz, 13.2125–13.25 GHz, 13.75–14.0 GHz, 14.0–14.5 GHz and
   15.43–15.63 GHz bands shall employ state-of-the-art full frequency reuse
   either through the use of orthogonal polarizations within the same beam
   and/or the use of spatially independent beams.

   (g)–(h) [Reserved]

   (i) Space station antennas in the Fixed-Satellite Service must be designed
   to provide a cross-polarization isolation such that the ratio of the on axis
   co-polar gain to the cross-polar gain of the antenna in the assigned
   frequency band shall be at least 30 dB within its primary coverage area.

   (j) Space stations operated in the geostationary satellite orbit must be
   maintained within 0.05 ° of their assigned orbital longitude in the east/west
   direction, unless specifically authorized by the Commission to operate with
   a different longitudinal tolerance, and except as provided in Section
   25.283(b) (End-of-life Disposal).

   (k) Antenna measurements of both co-polarized and cross-polarized
   performance must be made on all antennas employed by space stations both
   within the primary coverage area to facilitate coordination with other
   Commission space station licensees and outside the primary coverage area to
   facilitate international frequency coordination with other Administrations.
   The results of such measurements shall be submitted to the Commission within
   thirty days after preliminary in-orbit testing is completed.

   (l) All operators of space stations shall, on June 30 of each year, file a
   report with the International Bureau and the Commission's Columbia
   Operations Center in Columbia, Maryland, containing the following
   information current as of May 31 of that year:

   (1) Status of satellite construction and anticipated launch dates, including
   any major problems or delays encountered;

   (2) A listing of any non-scheduled transponder outages for more than thirty
   minutes and the cause(s) of such outages;

   (3) A detailed description of the utilization made of each transponder on
   each of the in-orbit satellites. This description should identify the total
   capacity or the percentage of time each transponder is actually used for
   transmission, and the amount of unused system capacity in the transponder.
   This information is not required for those transponders that are sold on a
   non-common carrier basis. In that case, operators should indicate the number
   of transponders sold on each in-satellite orbit.

   (4) Identification of any transponders not available for service or
   otherwise not performing to specifications, the cause of these difficulties,
   and the date any transponder was taken out of service or the malfunction
   identified.

   [ 58 FR 13420 , Mar. 11, 1993, as amended at  61 FR 9952 , Mar. 12, 1996;  62 FR 5931 , Feb. 10, 1997;  62 FR 61457 , Nov. 18, 1997;  68 FR 51508 , Aug. 27, 2003;
    69 FR 54587 , Sept. 9, 2004;  70 FR 32256 , June 2, 2005]