§  25.264   Requirements to facilitate reverse-band operation in the 17.3-17.8
GHz band of 17/24 GHz BSS and DBS Service space stations.

   (a) Each 17/24 GHz BSS space station applicant or licensee must submit
   a series of tables or graphs containing predicted off-axis gain data
   for each antenna that will transmit in the 17.3-17.8 GHz frequency
   band, in accordance with the following specifications. Using a
   Cartesian coordinate system wherein the X axis is tangent to the
   geostationary orbital arc with the positive direction pointing east,
   i.e., in the direction of travel of the satellite; the Y axis is
   parallel to a line passing through the geographic north and south poles
   of the Earth, with the positive direction pointing south; and the Z
   axis passes through the satellite and the center of the Earth, with the
   positive direction pointing toward the Earth, the applicant or licensee
   must provide the predicted transmitting antenna off-axis antenna gain
   information:

   (1) In the X-Z plane, i.e., the plane of the geostationary orbit, over
   a range of ±30 degrees from the positive and negative X axes in
   increments of 5 degrees or less.

   (2) In planes rotated from the X-Z plane about the Z axis, over a range
   of ±60 degrees relative to the equatorial plane, in increments of 10
   degrees or less.

   (3) In both polarizations.

   (4) At a minimum of three measurement frequencies determined with
   respect to the entire portion of the 17.3-17.8 GHz frequency band over
   which the space station is designed to transmit: 5 MHz above the lower
   edge of the band; at the band center frequency; and 5 MHz below the
   upper edge of the band.

   (5) Over a greater angular measurement range, if necessary, to account
   for any planned spacecraft orientation bias or change in operating
   orientation relative to the reference coordinate system. The applicant
   or licensee must state the reasons for including such additional
   information.

   (6) The predictive gain information must be submitted to the Commission
   when a license application is filed for a 17/24 GHz BSS space station
   or within 60 days after completion of critical design review for the
   space station, whichever occurs later.

   (b) A 17/24 GHz BSS space station applicant or licensee must submit
   power flux density (pfd) calculations based on the predicted gain data
   submitted in accordance with paragraph (a) of this section, as follows:

   (1) The pfd calculations must be provided at the location of all
   prior-filed U.S. DBS space stations where the applicant's pfd level
   exceeds the coordination trigger of -117 dBW/m2/100 kHz in the
   17.3-17.8 GHz band. In this rule, the term prior-filed U.S. DBS space
   station refers to any co-frequency Direct Broadcast Satellite service
   space station for which an application was filed with the Commission,
   or an authorization was granted by the Commission, prior to the filing
   of the information and certifications required by paragraphs (a) and
   (b) of this section. The term prior-filed U.S. DBS space station does
   not include any applications (or authorizations) that have been denied,
   dismissed, or are otherwise no longer valid. Prior-filed U.S. DBS space
   stations may include foreign-licensed DBS space stations seeking
   authority to serve the United States market, but do not include
   foreign-licensed DBS space stations that have not filed applications
   with the Commission for market access in the United States.

   (2) The pfd calculations must take into account the maximum permitted
   longitudinal station-keeping tolerance, orbital inclination and orbital
   eccentricity of both the 17/24 GHz BSS and DBS space stations, and
   must:

   (i) Identify each prior-filed U.S. DBS space station at whose location
   the coordination threshold pfd level of -117 dBW/m2/100 kHz is
   exceeded; and

   (ii) Indicate the extent to which the calculated pfd of the 17/24 GHz
   space station's transmissions in the 17.3-17.8 GHz band exceed the
   threshold pfd level of -117 dBW/m2/100 kHz at those prior-filed U.S.
   DBS space station locations.

   (3) If the calculated pfd exceeds the threshold level of -117
   dBW/m2/100 kHz at the location of any prior-filed U.S. DBS space
   station, the applicant or licensee must also provide with the pfd
   calculations a certification that all affected DBS operators
   acknowledge and do not object to such higher off-axis pfd levels. No
   such certification is required in cases where the DBS and 17/24 GHz BSS
   assigned operating frequencies do not overlap.

   (4) The information and any certification required by paragraph (b) of
   this section must be submitted to the Commission when a license
   application is filed for a 17/24 GHz BSS space station or within 60
   days after completion of critical design review for the space station,
   whichever occurs later. Otherwise, such information and certifications
   must be submitted to the Commission within 24 months after the grant of
   an operating license for a 17/24 GHz BSS space station or when the
   applicant or licensee certifies completion of critical design review,
   whichever occurs first.

   (c) No later than 2 months prior to launch, each 17/24 GHz BSS space
   station licensee must update the predicted transmitting antenna
   off-axis gain information provided in accordance with paragraph (a) of
   this section by submitting measured transmitting antenna off-axis gain
   information over the angular ranges, measurement frequencies and
   polarizations specified in paragraphs (a)(1) through (5) of this
   section. The transmitting antenna off-axis gain information should be
   measured under conditions as close to flight configuration as possible.

   (d) No later than 2 months prior to launch, or when applying for
   authority to change the location of a 17/24 GHz BSS space station that
   is already in orbit, each 17/24 GHz BSS space station licensee must
   provide pfd calculations based on the measured off-axis gain data
   submitted in accordance with paragraph (c) of this section, as follows:

   (1) The pfd calculations must be provided:

   (i) At the location of all prior-filed U.S. DBS space stations as
   defined in paragraph (b)(1) of this section, where the applicant's pfd
   level in the 17.3-17.8 GHz band exceeds the coordination trigger of
   -117 dBW/m2/100 kHz; and

   (ii) At the location of any subsequently filed U.S. DBS space station
   where the pfd level in the 17.3-17.8 GHz band calculated on the basis
   of measured gain data exceeds -117 dBW/m2/100 kHz. In this rule, the
   term subsequently filed U.S. DBS space station refers to any
   co-frequency Direct Broadcast Satellite service space station proposed
   in a license application filed with the Commission after the 17/24 GHz
   BSS operator submitted the predicted data required by paragraphs (a)
   through (b) of this section but before submission of the measured data
   required by this paragraph. Subsequently-filed U.S. DBS space stations
   may include foreign-licensed DBS space stations seeking authority to
   serve the United States market. The term does not include any
   applications (or authorizations) that have been denied, dismissed, or
   are otherwise no longer valid, nor does it include foreign-licensed DBS
   space stations that have not filed applications with the Commission for
   market access in the United States.

   (2) The pfd calculations must take into account the maximum permitted
   longitudinal station-keeping tolerance, orbital inclination and orbital
   eccentricity of both the 17/24 GHz BSS and DBS space stations, and
   must:

   (i) Identify each prior-filed U.S. DBS space station at whose location
   the coordination threshold pfd level of -117 dBW/m2/100 kHz is
   exceeded; and

   (ii) Demonstrate the extent to which the applicant's or licensee's
   transmissions in the 17.3-17.8 GHz band exceed the threshold pfd level
   of -117 dBW/m2/100 kHz at those prior-filed U.S. DBS space station
   locations.

   (e) If the pfd level calculated from the measured data submitted in
   accordance with paragraph (d) of this section is in excess of the
   threshold pfd level of -117 dBW/m2/100 kHz:

   (1) At the location of any prior-filed U.S. DBS space station as
   defined in paragraph (b)(1) of this section, then the 17/24 GHz
   broadcasting-satellite operator must either:

   (i) Coordinate its operations that are in excess of the threshold pfd
   level of -117 dBW/m2/100 kHz with the affected prior-filed U.S. DBS
   space station operator, or

   (ii) Adjust its operating parameters so that at the location of the
   prior-filed U.S. DBS space station, the pfd level of -117 dBW/m2/100
   kHz is not exceeded.

   (2) At the location of any subsequently-filed U.S. DBS space station as
   defined in paragraph (d)(1) of this section, where the pfd level
   submitted in accordance with paragraph (d) of this section, is also in
   excess of the pfd level calculated on the basis of the predicted data
   submitted in accordance with paragraph (a) of this section that were on
   file with the Commission at the time the DBS space station application
   was filed, then the 17/24 GHz broadcasting-satellite operator must
   either:

   (i) Coordinate with the affected subsequently-filed U.S. DBS space
   station operator all of its operations that are either in excess of the
   pfd level calculated on the basis of the predicted antenna off-axis
   gain data, or are in excess of the threshold pfd level of -117
   dBW/m2/100 kHz, whichever is greater, or

   (ii) Adjust its operating parameters so that at the location of the
   subsequently-filed U.S. DBS space station, either the pfd level
   calculated on the basis of the predicted off-axis transmitting antenna
   gain data, or the threshold pfd level of -117 dBW/m2/100 kHz, whichever
   is greater, is not exceeded.

   (3) No coordination or adjustment of operating parameters is required
   in cases where the DBS and 17/24 GHz BSS operating frequencies do not
   overlap.

   (f) The 17/24 GHz BSS applicant or licensee must modify its license, or
   amend its application, as appropriate, based upon new information:

   (1) If the pfd levels submitted in accordance with paragraph (d) of
   this section, are in excess of those submitted in accordance with
   paragraph (b) of this section at the location of any prior-filed or
   subsequently-filed U.S. DBS space station as defined in paragraphs
   (b)(1) and (d)(1)of this section, or

   (2) If the 17/24 GHz BSS operator adjusts its operating parameters in
   accordance with paragraphs (e)(1)(ii) or (e)(2)(ii) or this section.

   (g) Absent an explicit agreement between operators to permit more
   closely spaced operations, U.S. authorized 17/24 GHz BSS space stations
   and U.S. authorized DBS space stations with co-frequency assignments
   may not be licensed to operate at locations separated by less than 0.2
   degrees in orbital longitude.

   (h) All operational 17/24 GHz BSS space stations must be maintained in
   geostationary orbits that:

   (1) Do not exceed 0.075° of inclination.

   (2) Operate with an apogee less than or equal to 35,806 km above the
   surface of the Earth, and with a perigee greater than or equal to
   35,766 km above the surface of the Earth (i.e., an eccentricity of less
   than 4.7 × 10-4).

   (i) U.S. authorized DBS networks may claim protection from space path
   interference arising from the reverse-band operations of U.S.
   authorized 17/24 GHz BSS networks to the extent that the DBS space
   station operates within the bounds of inclination and eccentricity
   listed below. When the geostationary orbit of the DBS space station
   exceeds these bounds on inclination and eccentricity, it may not claim
   protection from any additional space path interference arising as a
   result of its inclined or eccentric operations and may only claim
   protection as if it were operating within the bounds listed below:

   (1) The DBS space station's orbit does not exceed 0.075° of
   inclination, and

   (2) The DBS space station's orbit maintains an apogee less than or
   equal to 35,806 km above the surface of the Earth, and a perigee
   greater than or equal to 35,766 km above the surface of the Earth
   (i.e., an eccentricity of less than 4.7 × 10-4).

   [ 76 FR 50431 , Aug. 15, 2011, as amended at  81 FR 55348 , Aug. 18, 2016]