§  25.201   Definitions.

   Definitions for terms in subpart C of this part appear in this section,
   and in §  2.1 of this chapter.

   1.5/1.6 GHz Mobile-Satellite Service. Mobile-Satellite Service provided
   in any portions of the 1525-1559 MHz downlink band and the
   1626.5-1660.5 MHz uplink band, which are referred to in this rule part
   as the "1.5/1.6 GHz MSS bands."

   1.6/2.4 GHz Mobile-Satellite Service. A mobile-satellite service that
   operates in the 1610-1626.5 MHz and 2483.5-2500 MHz frequency bands, or
   in any portion thereof.

   2 GHz Mobile-Satellite Service. A Mobile-Satellite Service that is
   operated in the 2000-2020 MHz and 2180-2200 MHz bands, or in any
   portion thereof.

   17/24 GHz Broadcasting-Satellite Service. A radiocommunications service
   using geostationary satellites between one or more feeder link earth
   stations and other earth stations, in the 17.3--17.7 GHz
   (space-to-Earth) (domestic allocation), 17.3--17.8 GHz (international
   allocation) and 24.75--25.25 GHz frequency bands. This service is also
   known as "17/24 GHz BSS." For purposes of the application processing
   provisions of this part, 17/24 GHz BSS is a GSO-like service. For
   purposes of the technical requirements of this part, we will treat
   17/24 GHz BSS as if it were FSS. Unless specifically stated otherwise,
   the 17/24 GHz BSS systems are subject to the rules in this part
   applicable to FSS.

   Ambulatory. Not stationary. Baselines from which maritime boundaries
   are measured change with accretion- and erosion-caused ambulation of
   the boundaries themselves.

   Ancillary terrestrial component. The term "ancillary terrestrial
   component" means a terrestrial communications network used in
   conjunction with a qualifying satellite network system authorized
   pursuant to these rules and the conditions established in the Orders
   issued in IB Docket No. 01-185, Flexibility for Delivery of
   Communications by Mobile Satellite Service Providers in the 2 GHz Band,
   the L-Band, and the 1.6/2.4 GHz Band.

   Ancillary terrestrial component base station. The term "ancillary
   terrestrial component base station" means a terrestrial fixed facility
   used to transmit communications to or receive communications from one
   or more ancillary terrestrial component mobile terminals.

   Ancillary terrestrial component mobile terminal. The term "ancillary
   terrestrial component mobile terminal" means a terrestrial mobile
   facility used to transmit communications to or receive communications
   from an ancillary terrestrial component base station or a space
   station.

   Baseline. The line from which maritime zones are measured, also known
   as the coast line. The baseline is a combination of the low-water line
   ("low-tide elevation") and closing lines across the mouths of inland
   water bodies. The baseline is defined by a series of baseline points.
   The baseline points are not just the low-water marks of the shore of
   mainland but also includes islands and "low-water elevations" ( i.e. ,
   natural rocks). Baseline points are ambulatory, and thus, require
   adjustment from time-to-time by the U.S. Department of State's Baseline
   Committee.

   C-band. For purposes of this part, the terms "C-band" and "conventional
   C-band" refer specifically to the 3700-4200 MHz downlink and 5925-6425
   MHz uplink frequency bands. These paired bands are allocated to the
   Fixed-Satellite Service and are also referred to as the 4/6 GHz
   band(s).

   Coordination distance. For the purposes of this part, the expression
   "coordination distance" means the distance from an earth station,
   within which there is a possibility of the use of a given transmitting
   frequency at this earth station causing harmful interference to
   stations in the fixed or mobile service, sharing the same band, or of
   the use of a given frequency for reception at this earth station
   receiving harmful interference from such stations in the fixed or
   mobile service.

   Direct Broadcast Satellite Service. A radiocommunication service in
   which signals transmitted or retransmitted by space stations, using
   frequencies specified in §  25.202(a)(7), are intended for direct
   reception by the general public. For the purposes of this definition,
   the term direct reception shall encompass both individual reception and
   community reception.

   Earth station. A station located either on the Earth's surface or
   within the major portion of the Earth's atmosphere intended for
   communication:

   (a) With one or more space stations; or

   (b) With one or more stations of the same kind by means of one or more
   reflecting satellites or other objects in space.

   Earth Station on Vessel ("ESV"). An ESV is an earth station onboard a
   craft designed for traveling on water receiving from and transmitting
   to Fixed-Satellite Service space stations.

   Earth Stations Aboard Aircraft (ESAA). ESAA is an earth station or
   earth stations, operating from an aircraft, that receives from and
   transmits to geostationary satellite orbit Fixed-Satellite Service
   space stations and operates within the United States pursuant to the
   requirements set out §  25.227.

   Electronic filing. The submission of applications, exhibits, pleadings,
   or other filings to the Commission in an electronic form using Internet
   or World Wide Web on-line filing forms.

   Equivalent diameter. When circular aperture reflector antennas are
   employed, the size of the antenna is generally expressed as the
   diameter of the antenna's main reflector. When non-reflector or
   non-circular aperture antennas are employed, an equivalent diameter can
   be computed for the antenna. The equivalent diameter is the diameter of
   a hypothetical circular aperture antenna with the same aperture area as
   the actual antenna. For example, an elliptical aperture antenna with
   major axis, a , and minor axis, b , will have an equivalent diameter of
   [ a * b ]1/2 . A rectangular aperture antenna with length, l , and
   width, w , will have an equivalent diameter of [4( l * w )/p]1/2 .

   Equivalent power flux density. Equivalent power flux density (EPFD) is
   the sum of the power flux-densities produced at a geostationary
   satellite orbit (GSO) receive earth or space station on the Earth's
   surface or in the geostationary satellite orbit, as appropriate, by all
   the transmit stations within a non-geostationary satellite orbit
   Fixed-Satellite Service (NGSO FSS) system, taking into account the
   off-axis discrimination of a reference receiving antenna assumed to be
   pointing in its nominal direction. The equivalent power flux density,
   in dB(W/m2 ) in the reference bandwidth, is calculated using the
   following formula:
   eCFR graphic er06fe13.043.gif

   View or download PDF

   Where:

   N a is the number of transmit stations in the non-geostationary
   satellite orbit system that are visible from the GSO receive station
   considered on the Earth's surface or in the geostationary satellite
   orbit, as appropriate;

   i is the index of the transmit station considered in the
   non-geostationary satellite orbit system;

   P i is the RF power at the input of the antenna of the transmit
   station, considered in the non-geostationary satellite orbit system in
   dBW in the reference bandwidth;

   thi is the off-axis angle between the boresight of the transmit station
   considered in the non-geostationary satellite orbit system and the
   direction of the GSO receive station;

   G t (thi ) is the transmit antenna gain (as a ratio) of the station
   considered in the non-geostationary satellite orbit system in the
   direction of the GSO receive station;

   d i is the distance in meters between the transmit station considered
   in the non-geostationary satellite orbit system and the GSO receive
   station;

   Fi is the off-axis angle between the boresight of the antenna of the
   GSO receive station and the direction of the i th transmit station
   considered in the non-geostationary satellite orbit system;

   G r (Fi ) is the receive antenna gain (as a ratio) of the GSO receive
   station in the direction of the i th transmit station considered in the
   non-geostationary satellite orbit system;

   G r ,max is the maximum gain (as a ratio) of the antenna of the GSO
   receive station.

   Feeder link. A radio link from an earth station at a given location to
   a space station, or vice versa, conveying information for a space
   radiocommunication service other than the Fixed-Satellite Service. The
   given location may be at a specified fixed point or at any fixed point
   within specified areas. (RR)

   Fixed earth station. An earth station intended to be used at a fixed
   position. The position may be a specified fixed point or any fixed
   point within a specified area.

   Fixed-Satellite Service. A radiocommunication service between earth
   stations at given positions, when one or more satellites are used; the
   given position may be a specified fixed point or any fixed point within
   specified areas; in some cases this service includes
   satellite-to-satellite links, which may also be operated in the
   inter-satellite service; the Fixed-Satellite Service may also include
   feeder links of other space radiocommunication services. (RR)

   Fixed earth station. An earth station intended to be used at a fixed
   position. The position may be a specified fixed point or any fixed
   point within a specified area.

   Fixed-Satellite Service. A radiocommunication service between earth
   stations at given positions, when one or more satellites are used; the
   given position may be a specified fixed point or any fixed point within
   specified areas; in some cases this service includes
   satellite-to-satellite links, which may also be operated in the
   inter-satellite service; the Fixed-Satellite Service may also include
   feeder links of other space radiocommunication services. (RR)

   Geostationary satellite. A geosynchronous satellite whose circular and
   direct orbit lies in the plane of the Earth's equator and which thus
   remains fixed relative to the Earth; by extension, a satellite which
   remains approximately fixed relative to the Earth.

   Inter-Satellite Service. A radiocommunication service providing links
   between artificial earth satellites.

   Land earth station. An earth station in the Fixed-Satellite Service or,
   in some cases, in the Mobile-Satellite Service, located at a specified
   fixed point or within a specified area on land to provide a feeder link
   for the Mobile-Satellite Service. (RR)

   Land Mobile Earth Station. A mobile earth station in the land
   mobile-satellite service capable of surface movement within the
   geographical limits of a country or continent. (RR)

   Ku-band. In this rule part, the terms "Ku-band" and "conventional
   Ku-band" refer specifically to the 11700-12200 MHz downlink and
   14000-14500 MHz uplink frequency bands. These paired bands are
   allocated to the Fixed-Satellite Service and are also referred to as
   the 12/14 GHz band(s).

   Low-Tide Elevation. A naturally formed area of land that is surrounded
   by and above water at low tide but below water at high tide. Low-tide
   elevations serve as part of the coast line when they are within the
   breath of the territorial sea of the mainland (either uplands or inland
   waters) or an island. 1958 Convention on the Territorial Sea, Article
   11.

   Mobile earth station. An earth station intended to be used while in
   motion or during halts at unspecified points.

   Mobile-Satellite Service. A radiocommunication service:

   (1) Between mobile earth stations and one or more space stations, or
   between space stations used by this service; or

   (2) Between mobile earth stations, by means of one or more space
   stations.

   This service may also include feeder links necessary for its operation.
   (RR)

   NGSO FSS gateway earth station. A gateway earth station is an earth
   station complex consisting of multiple interconnecting earth station
   antennas supporting the communication routing and switching functions
   of a non-geostationary satellite orbit fixed-satellite service (NGSO
   FSS) system as a whole. A gateway earth station in the NGSO FS§ 

   (1) Does not originate or terminate radiocommunication traffic, but
   interconnects multiple non-collocated user earth stations operating in
   frequency bands other than designated gateway bands, through a
   satellite with other primary terrestrial networks, such as the public
   switched telephone network (PSTN) and/or Internet networks.

   (2) Shall not be for the exclusive use of any customer.

   (3) May also be used for telemetry, tracking, and command transmissions
   for the same NGSO FSS system.

   (4) May include multiple antennas, each required to meet the antenna
   performance standard in §  25.209(h), located within an area of one
   second latitude by one second longitude.

   (5) Is considered as a separate gateway earth station complex if it is
   out side of the area of one second latitude by one second longitude of
   paragraph (4) of this definition, for the purposes of coordination with
   terrestrial services.

   Non-Voice, Non-Geostationary Mobile-Satellite Service. A
   Mobile-Satellite Service reserved for use by non-geostationary
   satellites in the provision of non-voice communications which may
   include satellite links between land earth stations at fixed locations.

   Permitted Space Station List. A list of satellites operating in the
   C-band and/or Ku-band including all U.S.-licensed satellites and those
   non-U.S.-licensed satellites for which the Commission has authorized
   routine U.S.-licensed earth stations to communicate with that
   satellite, and the satellite operator has requested the Commission to
   place its satellite on the Permitted Space Station List.

   Power flux density. The amount of power flow through a unit area within
   a unit bandwidth. The units of power flux density are those of power
   spectral density per unit area, namely watts per hertz per square
   meter. These units are generally expressed in decibel form as
   dB(W/Hz/m2 ), dB(W/m2 ) in a 4 kHz band, or dB(W/m2 ) in a 1 MHz band.

   Power spectral density. The amount of an emission's transmitted carrier
   power applied at the antenna input falling within the stated bandwidth.
   The units of power spectral density are watts per hertz and are
   generally expressed in decibel form as dB(W/Hz) when measured in a 1 Hz
   bandwidth, dB(W/4kHz) when measured in a 4 kHz bandwidth, or dB(W/1MHz)
   when measured in a 1 MHz bandwidth.

   Protection areas. The geographic regions on the surface of the Earth
   where U.S. Department of Defense meteorological satellite systems or
   National Oceanic and Atmospheric Administration meteorological
   satellite systems, or both such systems, are receiving signals from low
   earth orbiting satellites. Also, geographic protection areas around
   Ka-band feeder-link earth stations in the 1.6/2.4 GHz Mobile-Satellite
   Service are determined in the manner specified in §  25.203(j).

   Radiodetermination-Satellite Service. A radiocommunication service for
   the purpose of radiodetermination involving the use of one of more
   space stations. This service may also include feeder links necessary
   for its own operation. (RR)

   Routine processing or licensing. A licensing process whereby
   applications are processed in an expedited manner. To be eligible for
   routine processing, an application must be complete in all regards,
   must be consistent with all Commission Rules, and must not raise any
   policy issues. With respect to fixed earth station licensing (including
   temporary fixed stations), an application is "routine" only if it is
   for an individual earth station that conforms to all applicable
   provisions of the Commission's rules pertaining to antenna performance,
   power, frequency coordination, radiation hazard, and FAA notification,
   and accesses only "Permitted Space Station List" satellites in the
   conventional C-band or Ku-band frequency bands.

   Satellite Digital Audio Radio Service ("DARS"). A radiocommunication
   service in which audio programming is digitally transmitted by one or
   more space stations directly to fixed, mobile, and/or portable
   stations, and which may involve complementary repeating terrestrial
   transmitters, telemetry, tracking and control facilities.

   Satellite system. A space system using one or more artificial earth
   satellites.

   Selected assignment. The term "selected assignment" means a spectrum
   assignment voluntarily identified by a 2 GHz MSS licensee at the time
   that the licensee's first 2 GHz mobile-satellite service satellite
   reaches its intended orbit, or other mobile-satellite service spectrum
   in which the Commission permits a 2 GHz mobile-satellite service
   licensee to conduct mobile-satellite service operations with authority
   superior to that of other in-band, mobile-satellite service licensees.

   Spacecraft. A man-made vehicle which is intended to go beyond the major
   portion of the Earth's atmosphere.

   Space operation service. A radiocommunication service concerned
   exclusively with the operation of spacecraft, in particular space
   tracking, space telemetry and space telecommand. These functions will
   normally be provided within the service in which the space station is
   operating.

   Space radiocommunication. Any radiocommunication involving the use of
   one or more space stations or the use of one or more reflecting
   satellites or other objects in space.

   Space station. A station located on an object which is beyond, is
   intended to go beyond, or has been beyond, the major portion of the
   Earth's atmosphere.

   Space system. Any group of cooperating earth stations and/or space
   stations employing space radiocommunication for specific purposes.

   Terrestrial radiocommunication. Any radiocommunication other than space
   radiocommunication or radio astronomy.

   Terrestrial station. A station effecting terrestrial
   radiocommunication.

   Vehicle-mounted earth station (VMES). A VMES is an earth station,
   operating from a motorized vehicle that travels primarily on land, that
   receives from and transmits to geostationary satellite orbit
   Fixed-Satellite Service space stations and operates within the United
   States pursuant to the requirements set out in §  25.226.

   [ 30 FR 7176 , May 28, 1965]

   Editorial Note: For Federal Register citations affecting §  25.201, see
   the List of CFR Sections Affected, which appears in the Finding Aids
   section of the printed volume and at www.fdsys.gov .

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