§ 25.202   Frequencies, frequency tolerance, and emission limits.

   (a)(1) In addition to the frequency-use restrictions set forth in
   § 2.106 of this chapter, the following restrictions apply:

   (i) In the 27.5-28.35 GHz band, the FSS (Earth-to-space) is secondary
   to the Upper Microwave Flexible Use Service authorized pursuant to part
   30 of this chapter, except for FSS operations associated with earth
   stations authorized pursuant to § 25.136.

   (ii) Use of the 37.5-40 GHz band by the FSS (space-to-Earth) is limited
   to individually licensed earth stations. Earth stations in this band
   must not be ubiquitously deployed and must not be used to serve
   individual consumers.

   (iii) The U.S. non-Federal Table of Frequency Allocations, in § 2.106 of
   this chapter, is applicable between Commission space station licensees
   relying on a U.S. ITU filing and transmitting to or receiving from
   anywhere on Earth, including airborne earth stations, in the 17.7-20.2
   GHz or 27.5-30 GHz bands.

   (2) [Reserved]

   (3) The following frequencies are available for use by the non-voice,
   non-geostationary mobile-satellite service:

   137-138 MHz: Space-to-Earth

   148-150.05 MHz: Earth-to-space

   399.9-400.05 MHz: Earth-to-space

   400.15-401 MHz: Space-to-Earth

   (4)(i) The following frequencies are available for use by the 1.6/2.4
   GHz Mobile-Satellite Service:

   1610-1626.5 MHz: User-to-Satellite Link

   1613.8-1626.5 MHz: Satellite-to-User Link (secondary)

   2483.5-2500 MHz: Satellite-to-User Link

   (ii) The following frequencies are available for use by the 2 GHz
   Mobile-Satellite Service: 2000-2020 MHz: User-to-Satellite Link;
   2180-2200 MHz: Satellite-to-User Link.

   (iii)(A) The following frequencies are available for use by the 1.5/1.6
   GHz Mobile-Satellite Service:

   1525-1559 MHz: space-to-Earth

   1626.5-1660.5 MHz: Earth-to-space

   (B) The use of the frequencies 1544-1545 MHz and 1645.5-1646.5 MHz is
   limited to distress and safety communications.

   (5) The following frequencies are available for use by the
   inter-satellite service:

   22.55-23.00 GHz

   23.00-23.55 GHz

   24.45-24.65 GHz

   24.65-24.75 GHz

   54.25-56.90 GHz

   57.00-58.20 GHz

   65.00-71.00 GHz

   (6) The following frequencies are available for use by the Satellite
   Digital Audio Radio Service (SDARS), and for any associated terrestrial
   repeaters: 2320-2345 MHz (space-to-Earth)

   (7) The following frequencies are available for use by the Direct
   Broadcast Satellite service:

   12.2-12.7 GHz: Space-to-Earth.

   12.2-12.7 GHz: Space-to-Earth.

   (8) The following frequencies are available for use by ESVs:

   3700-4200 MHz (space-to-Earth)

   5925-6425 MHz (Earth-to-space)

   10.95-11.2 GHz (space-to-Earth)

   11.45-11.7 GHz (space-to-Earth)

   11.7-12.2 GHz (space-to-Earth)

   14.0-14.5 GHz (Earth-to-space)

   ESVs shall be authorized and coordinated as set forth in § § 25.221 and
   25.222. ESV operators, collectively, may coordinate up to 180 megahertz
   of spectrum in the 5925-6425 MHz (Earth-to-space) band for all ESV
   operations at any given location subject to coordination.

   (9) The following frequencies are available for use by the
   Broadcasting-Satellite Service after 1 April 2007:

   17.3-17.7 GHz (space-to-Earth)

   17.7-17.8 GHz (space-to-Earth)

   Note 1 to paragraph (a)(9): Use of the 17.3-17.7 GHz band by the
   broadcasting-satellite service is limited to geostationary satellite
   orbit systems.

   Note 2 to paragraph (a)(9): Use of the 17.7-17.8 GHz band
   (space-to-Earth) by the broadcasting-satellite service is limited to
   transmissions from geostationary satellite orbit systems to receiving
   earth stations located outside of the United States and its
   Possessions. In the United States and its Possessions, the 17.7-17.8
   GHz band is allocated on a primary basis to the Fixed Service.

   (10)(i) The following frequencies are available for use by
   Vehicle-Mounted Earth Stations (VMESs):

   10.95-11.2GHz (space-to-Earth)

   11.45-11.7GHz (space-to-Earth)

   11.7-12.2GHz (space-to-Earth)

   14.0-14.5GHz (Earth-to-space)

   (ii) VMESs shall be authorized as set forth in § 25.226.

   (11)(i) The following frequencies are available for use by Earth
   Stations Aboard Aircraft (ESAA):

   10.95-11.2 GHz (space-to-Earth)

   11.45-11.7 GHz (space-to-Earth)

   11.7-12.2 GHz (space-to-Earth)

   14.0-14.5 GHz (Earth-to-space)

   (ii) ESAAs shall be authorized as set forth in § 25.227.

   (12) The following frequencies are available for use by the
   mobile-satellite service (Earth-to-space) for the reception of
   Automatic Identification Systems (AIS) broadcast messages from ships:

   156.7625-156.7875 MHz

   156.8125-156.8375 MHz

   161.9625-161.9875 MHz

   162.0125-162.0375 MHz

   (b) Other frequencies and associated bandwidths of emission may be
   assigned on a case-by-case basis to space systems under this part in
   conformance with § 2.106 of this chapter and the Commission's rules and
   policies.

   (c) [Reserved]

   (d) Frequency tolerance, Earth stations. The carrier frequency of each
   earth station transmitter authorized in these services shall be
   maintained within 0.001 percent of the reference frequency.

   (e) Frequency tolerance, space stations. The carrier frequency of each
   space station transmitter authorized in these services shall be
   maintained within 0.002 percent of the reference frequency.

   (f) Emission limitations. Except for SDARS terrestrial repeaters and as
   provided for in paragraph (i), the mean power of emissions shall be
   attenuated below the mean output power of the transmitter in accordance
   with the schedule set forth in paragraphs (f)(1) through (f)(4) of this
   section. The out-of-band emissions of SDARS terrestrial repeaters shall
   be attenuated in accordance with the schedule set forth in paragraph
   (h) of this section.

   (1) In any 4 kHz band, the center frequency of which is removed from
   the assigned frequency by more than 50 percent up to and including 100
   percent of the authorized bandwidth: 25 dB;

   (2) In any 4 kHz band, the center frequency of which is removed from
   the assigned frequency by more than 100 percent up to and including 250
   percent of the authorized bandwidth: 35 dB;

   (3) In any 4 kHz band, the center frequency of which is removed from
   the assigned frequency by more than 250 percent of the authorized
   bandwidth: An amount equal to 43 dB plus 10 times the logarithm (to the
   base 10) of the transmitter power in watts;

   (4) In any event, when an emission outside of the authorized bandwidth
   causes harmful interference, the Commission may, at its discretion,
   require greater attenuation than specified in paragraphs (f) (1), (2)
   and (3) of this section.

   (g)(1) Telemetry, tracking, and command signals may be transmitted in
   frequencies within the assigned bands that are not at a band edge only
   if the transmissions cause no greater interference and require no
   greater protection from harmful interference than the communications
   traffic on the satellite network or have been coordinated with
   operators of authorized co-frequency space stations at orbital
   locations within six degrees of the assigned orbital location.

   (2) Frequencies, polarization, and coding of telemetry, tracking, and
   command transmissions must be selected to minimize interference into
   other satellite networks.

   (h) Out-of-band emission limitations for SDARS terrestrial repeaters.
   (1) Any SDARS terrestrial repeater operating at a power level greater
   than 2-watt average EIRP is required to attenuate its out-of-band
   emissions below the transmitter power P by a factor of not less than 90
   + 10 log (P) dB in a 1-megahertz bandwidth outside the 2320-2345 MHz
   band, where P is average transmitter output power in watts.

   (2) Any SDARS terrestrial repeater operating at a power level equal to
   or less than 2-watt average EIRP is required to attenuate its
   out-of-band emissions below the transmitter power P by a factor of not
   less than 75 + 10 log (P) dB in a 1-megahertz bandwidth outside the
   2320-2345 MHz band, where P is average transmitter output power in
   watts.

   (3) SDARS repeaters are permitted to attenuate out-of-band emissions
   less than the levels specified in paragraphs (h)(1) and (h)(2), of this
   section unless a potentially affected WCS licensee provides written
   notice that it intends to commence commercial service within the
   following 365 days. Starting 180 days after receipt of such written
   notice, SDARS repeaters within the area notified by the potentially
   affected WCS licensee must attenuate out-of-band emissions to the
   levels specified in paragraphs (h)(1) and (h)(2) of this section.

   (4) For the purpose of this section, a WCS licensee is potentially
   affected if it is authorized to operate a base station in the 2305-2315
   MHz or 2350-2360 MHz bands within 25 kilometers of a repeater seeking
   to operate with an out of band emission attenuation factor less than
   those prescribed in paragraphs (h)(1) or (2) of this section.

   (i) The WCS licensee is authorized to operate a base station in the
   2305-2315 MHz or 2350-2360 MHz bands in the same Major Economic Area
   (MEA) as that in which a SDARS terrestrial repeater is located.

   (ii) The WCS licensee is authorized to operate a base station in the
   2315-2320 MHz or 2345-2350 MHz bands in the same Regional Economic Area
   Grouping (REAG) as that in which a SDARS terrestrial repeater is
   located.

   (iii) A SDARS terrestrial repeater is located within 5 kilometers of
   the boundary of an MEA or REAG in which the WCS licensee is authorized
   to operate a WCS base station.

   (i) The following unwanted emissions power limits for non-geostationary
   satellites operating in the inter-satellite service that transmit in
   the 22.55-23.55 GHz band shall apply in any 200 MHz of the 23.6-24 GHz
   passive band, based on the date that complete advance publication
   information is received by the ITU's Radiocommunication Bureau:

   (1) For information received before January 1, 2020: −36 dBW.

   (2) For information received on or after January 1, 2020: −46 dBW.

   (j) For earth stations in the Fixed-Satellite Service (Earth-to-space)
   that transmit in the 49.7-50.2 GHz and 50.4-50.9 GHz bands, the
   unwanted emission power in the 50.2-50.4 GHz band shall not exceed −20
   dBW/200 MHz (measured at the input of the antenna), except that the
   maximum unwanted emission power may be increased to −10 dBW/200 MHz for
   earth stations having an antenna gain greater than or equal to 57 dBi.
   These limits apply under clear-sky conditions. During fading
   conditions, the limits may be exceeded by earth stations when using
   uplink power control.

   [ 30 FR 7176 , May 28, 1965]

   Editorial Note: For Federal Register citations affecting § 25.202, see
   the List of CFR Sections Affected, which appears in the Finding Aids
   section of the printed volume and at www.govinfo.gov.

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