[Code of Federal Regulations]

[Title 47, Volume 1]

[Revised as of October 1, 2006]

From the U.S. Government Printing Office via GPO Access

[CITE: 47CFR2.1]



[Page 526-538]

 

                       TITLE 47--TELECOMMUNICATION

 

              CHAPTER I--FEDERAL COMMUNICATIONS COMMISSION

 

PART 2_FREQUENCY ALLOCATIONS AND RADIO TREATY MATTERS; GENERAL RULES AND 

REGULATIONS--Table of Contents

 

                          Subpart A_Terminology

 

Sec.  2.1  Terms and definitions.





    (a) Where a term or definition appears in this part of the 

Commission's Rules, it shall be the definitive term or definition and 

shall prevail throughout the Commission's Rules.

    (b) The source of each definition is indicated as follows:



CS--Annex to the Constitution of the International Telecommunication 

    Union (ITU)

CV--Annex to the Convention of the ITU

FCC--Federal Communications Commission

RR--ITU Radio Regulations



    (c) The following terms and definitions are issued:

    Accepted Interference. \1\ Interference at a higher level than 

defined as permissible interference and which has been agreed upon 

between two or more administrations without prejudice to other 

administrations. (RR)

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    \1\ The terms permissible interference and accepted interference are 

used in the coordination of frequency assignments between 

administrations.

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    Active Satellite. A satellite carrying a station intended to 

transmit or retransmit radiocommunication signals. (RR)

    Active Sensor. A measuring instrument in the earth exploration-

satellite service or in the space research service by means of which 

information is obtained by transmission and reception of radio waves. 

(RR)

    Adaptive System. A radiocommunication system which varies its radio 

characteristics according to channel quality. (RR)

    Administration. Any governmental department or service responsible 

for discharging the obligations undertaken in the Constitution of the 

International Telecommunication Union, in the Convention of the 

International Telecommunication Union and in the Administrative 

Regulations. (CS)

    Aeronautical Earth Station. An Earth station in the fixed-satellite 

service, or, in some cases, in the aeronautical mobile-satellite 

service, located at a specified fixed point on land to provide a feeder 

link for the aeronautical mobile-satellite service. (RR)

    Aeronautical Fixed Service. A radiocommunication service between 

specified fixed points provided primarily for the safety of air 

navigation and for the regular, efficient and economical operation of 

air transport. (RR)

    Aeronautical Fixed Station. A station in the aeronautical fixed 

service. (RR)

    Aeronautical Mobile Off-Route (OR) Service. An aeronautical mobile 

service intended for communications, including those relating to flight 

coordination, primarily outside national or international civil air 

routes. (RR)

    Aeronautical Mobile Route (R) Service. An aeronautical mobile 

service reserved for communications relating to



[[Page 527]]



safety and regularity of flight, primarily along national or 

international civil air routes. (RR)

    Aeronautical Mobile-Satellite Off-Route (OR) Service. An 

aeronautical mobile-satellite service intended for communications, 

including those relating to flight coordination, primarily outside 

national and international civil air routes. (RR)

    Aeronautical Mobile-Satellite Route (R) Service. An aeronautical 

mobile-satellite service reserved for communications relating to safety 

and regularity of flights, primarily along national or international 

civil air routes. (RR)

    Aeronautical Mobile-Satellite Service. A mobile-satellite service in 

which mobile earth stations are located on board aircraft; survival 

craft stations and emergency position-indicating radiobeacon stations 

may also participate in this service. (RR)

    Aeronautical Mobile Service. A mobile service between aeronautical 

stations and aircraft stations, or between aircraft stations, in which 

survival craft stations may participate; emergency position-indicating 

radiobeacon stations may also participate in this service on designated 

distress and emergency frequencies. (RR)

    Aeronautical Radionavigation-Satellite Service. A radionavigation-

satellite service in which earth stations are located on board aircraft. 

(RR)

    Aeronautical Radionavigation Service. A radio-navigation service 

intended for the benefit and for the safe operation of aircraft. (RR)

    Aeronautical Station. A land station in the aeronautical mobile 

service.



    Note: In certain instances, an aeronautical station may be located, 

for example, on board ship or on a platform at sea. (RR)



    Aircraft Earth Station. A mobile earth station in the aeronautical 

mobile-satellite service located on board an aircraft. (RR)

    Aircraft Station. A mobile station in the aeronautical mobile 

service, other than a survival craft station, located on board an 

aircraft. (RR)

    Allocation (of a frequency band). Entry in the Table of Frequency 

Allocations of a given frequency band for the purpose of its use by one 

or more terrestrial or space radiocommunication services or the radio 

astronomy service under specified conditions. This term shall also be 

applied to the frequency band concerned. (RR)

    Allotment (of a radio frequency or radio frequency channel). Entry 

of a designated frequency channel in an agreed plan, adopted by a 

competent conference, for use by one or more administrations for a 

terrestrial or space radiocommunication service in one or more 

identified countries or geographical area and under specified 

conditions. (RR)

    Altitude of the Apogee or Perigee. The altitude of the apogee or 

perigee above a specified reference surface serving to represent the 

surface of the Earth. (RR)

    Amateur-Satellite Service. A radiocommunication service using space 

stations on earth satellites for the same purposes as those of the 

amateur service. (RR)

    Amateur Service. A radiocommunication service for the purpose of 

self-training, intercommunication and technical investigations carried 

out by amateurs, that is, by duly authorized persons interested in radio 

technique solely with a personal aim and without pecuniary interest. 

(RR)

    Amateur Station. A station in the amateur service. (RR)

    Assigned Frequency. The centre of the frequency band assigned to a 

station. (RR)

    Assigned Frequency Band. The frequency band within which the 

emission of a station is authorized; the width of the band equals the 

necessary bandwidth plus twice the absolute value of the frequency 

tolerance. Where space stations are concerned, the assigned frequency 

band includes twice the maximum Doppler shift that may occur in relation 

to any point of the Earth's surface. (RR)

    Assignment (of a radio frequency or radio frequency channel). 

Authorization given by an administration for a radio station to use a 

radio frequency or radio frequency channel under specified conditions. 

(RR)

    Base Earth Station. An earth station in the fixed-satellite service 

or, in some cases, in the land mobile-satellite service, located at a 

specified fixed point or within a specified area on land



[[Page 528]]



to provide a feeder link for the land mobile-satellite service. (RR)

    Base Station. A land station in the land mobile service. (RR)

    Broadcasting-Satellite Service. A radiocommunication service in 

which signals transmitted or retransmitted by space stations are 

intended for direct reception by the general public.



    Note: In the broadcasting-satellite service, the term direct 

reception shall encompass both individual reception and community 

reception. (RR)



    Broadcasting Service. A radiocommunication service in which the 

transmissions are intended for direct reception by the general public. 

This service may include sound transmissions, television transmissions 

or other types of transmission. (CS)

    Broadcasting Station. A station in the broadcasting service. (RR)

    Carrier Power (of a radio transmitter). The average power supplied 

to the antenna transmission line by a transmitter during one radio 

frequency cycle taken under the condition of no modulation. (RR)

    Characteristic Frequency. A frequency which can be easily identified 

and measured in a given emission.



    Note: A carrier frequency may, for example, be designated as the 

characteristic frequency. (RR)



    Class of Emission. The set of characteristics of an emission, 

designated by standard symbols, e.g., type of modulation, modulating 

signal, type of information to be transmitted, and also if appropriate, 

any additional signal characteristics. (RR)

    Coast Earth Station. An earth station in the fixed-satellite service 

or, in some cases, in the maritime mobile-satellite service, located at 

a specified fixed point on land to provide a feeder link for the 

maritime mobile-satellite service. (RR)

    Coast Station. A land station in the maritime mobile service. (RR)

    Community Reception (in the broadcasting-satellite service). The 

reception of emissions from a space station in the broadcasting-

satellite service by receiving equipment, which in some cases may be 

complex and have antennae larger than those for individual reception, 

and intended for use: (1) by a group of the general public at one 

location; or (2) through a distribution system covering a limited area. 

(RR)

    Coordinated Universal Time (UTC). Time scale, based on the second 

(SI), as defined in Recommendation ITU-R TF.460-6.



    Note: For most practical purposes associated with the ITU Radio 

Regulations, UTC is equivalent to mean solar time at the prime meridian 

(0[deg] longitude), formerly expressed in GMT. (RR)



    Coordination Area. When determining the need for coordination, the 

area surrounding an earth station sharing the same frequency band with 

terrestrial stations, or surrounding a transmitting earth station 

sharing the same bidirectionally allocated frequency band with receiving 

earth stations, beyond which the level of permissible interference will 

not be exceeded and coordination is therefore not required. (RR)

    Coordination Contour. The line enclosing the coordination area. (RR)

    Coordination Distance. When determining the need for coordination, 

the distance on a given azimuth from an earth station sharing the same 

frequency band with terrestrial stations, or from a transmitting earth 

station sharing the same bidirectionally allocated frequency band with 

receiving earth stations, beyond which the level of permissible 

interference will not be exceeded and coordination is therefore not 

required. (RR)

    Deep Space. Space at distance from the Earth equal to, or greater 

than, 2x10\6\ kilometers. (RR)

    Differential Global Positioning System (DGPS) Station. A 

differential RNSS station for specific augmentation of GPS.

    Differential Radionavigation Satellite Service (Differential RNSS) 

Station. A station used for the transmission of differential correction 

data and related information (such as ionospheric data and RNSS 

satellite integrity information) as an augmentation to an RNSS system 

for the purpose of improved navigation accuracy.

    Direct Sequence Systems. A spread spectrum system in which the 

carrier has been modulated by a high speed spreading code and an 

information data stream. The high speed code sequence



[[Page 529]]



dominates the ``modulating function'' and is the direct cause of the 

wide spreading of the transmitted signal.

    Duplex Operation. Operating method in which transmission is possible 

simultaneously in both directions of a telecommunication channel. \3\ 

(RR)

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    \3\ In general, duplex operation and semi-duplex operation require 

two frequencies in radiocommunication; simplex operation may use either 

one or two.

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    Earth Exploration-Satellite Service. A radiocommunication service 

between earth stations and one or more space stations, which may include 

links between space stations in which:

    (1) Information relating to the characteristics of the Earth and its 

natural phenomena is obtained from active sensors or passive sensors on 

earth satellites;

    (2) Similar information is collected from air-borne or earth-based 

platforms;

    (3) Such information may be distributed to earth stations within the 

system concerned;

    (4) Platform interrogation may be included.



    Note: This service may also include feeder links necesary for its 

operation. (RR)



    Earth Station. A station located either on the earth's surface or 

within the major portion of earth's atmosphere and intended for 

communication:

    (1) With one or more space stations; or

    (2) With one or more stations of the same kind by means of one or 

more reflecting satellites or other objects in space. (RR)

    Effective Radiated Power (e.r.p) (in a given direction). The product 

of the power supplied to the antenna and its gain relative to a half-

wave dipole in a given direction. (RR)

    Emergency Position-Indicating Radiobeacon Station. A station in the 

mobile service the emissions of which are intended to facilitate search 

and rescue operations. (RR)

    Emission. Radiation produced, or the production of radiation, by a 

radio transmitting station.



    Note: For example, the energy radiated by the local oscillator of a 

radio receiver would not be an emission but a radiation. (RR)



    Equivalent Isotropically Radiated Power (e.i.r.p.). The product of 

the power suppled to the antenna and the antenna gain in a given 

direction relative to an isotropic antenna. (RR)

    Equivalent Monopole Radiated Power (e.m.r.p.) (in a given 

direction). The product of the power supplied to the antenna and its 

gain relative to a short vertical antenna in a given direction. (RR)

    Equivalent Satellite Link Noise Temperature. The noise temperature 

referred to the output of the receiving antenna of the earth station 

corresponding to the radio-frequency noise power which produces the 

total observed noise at the output of the satellite link excluding the 

noise due to interference coming from satellite links using other 

satellites and from terrestrial systems. (RR)

    Experimental Station. A station utilizing radio waves in experiments 

with a view to the development of science or technique.



    Note: This definition does not include amateur stations. (RR)



    Facsimile. A form of telegraphy for the transmission of fixed 

images, with or without half-tones, with a view to their reproduction in 

a permanent form. (RR)

    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 for the fixed-satellite service. 

The given location may be at a specified fixed point, or at any fixed 

point within specified areas. (RR)

    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 for 

other space radiocommunication services. (RR)

    Fixed Service. A radiocommunication service between specified fixed 

points. (RR)



[[Page 530]]



    Fixed Station. A station in the fixed service. (RR)

    Frequency Assignment Subcommittee (FAS). A subcommittee of the 

Interdepartment Radio Advisory Committee (IRAC) within NTIA that 

develops and executes procedures for the assignment and coordination of 

Federal radio frequencies. (FCC)

    Frequency Hopping Systems. A spread spectrum system in which the 

carrier is modulated with the coded information in a conventional manner 

causing a conventional spreading of the RF energy about the frequency 

carrier. The frequency of the carrier is not fixed but changes at fixed 

intervals under the direction of a coded sequence. The wide RF bandwidth 

needed by such a system is not required by spreading of the RF energy 

about the carrier but rather to accommodate the range of frequencies to 

which the carrier frequency can hop. The test of a frequency hopping 

system is that the near term distribution of hops appears random, the 

long term distribution appears evenly distributed over the hop set, and 

sequential hops are randomly distributed in both direction and magnitude 

of change in the hop set.

    Frequency-Shift Telegraphy. Telegraphy by frequency modulation in 

which the telegraph signal shifts the frequency of the carrier between 

predetermined values. (RR)

    Frequency Tolerance. The maximum permissible departure by the centre 

frequency of the frequency band occupied by an emission from the 

assigned frequency or, by the characteristic frequency of an emission 

from the reference frequency.



    Note: The frequency tolerance is expressed in parts in 10\6\ or in 

hertz. (RR)



    Full Carrier Single-Sideband Emission. A single-sideband emission 

without suppression of the carrier. (RR)

    Gain of an Antenna. The ratio, usually expressed in decibels, of the 

power required at the input of a loss free reference antenna to the 

power supplied to the input of the given antenna to produce, in a given 

direction, the same field strength or the same power flux-density at the 

same distance. When not specified otherwise, the gain refers to the 

direction of maximum radiation. The gain may be considered for a 

specified polarization.



    Note: Depending on the choice of the reference antenna a distinction 

is made between:

    (1) Absolute or isotropic gain (Gi), when the reference antenna is 

an isotropic antenna isolated in space;

    (2) Gain relative to a half-wave dipole (Gd), when the reference 

antenna is a half-wave dipole isolated in space whose equatorial plane 

contains the given direction;

    (3) Gain relative to a short vertical antenna (Gv), when the 

reference antenna is a linear conductor, much shorter than one quarter 

of the wavelength, normal to the surface of a perfectly conducting plane 

which contains the given direction. (RR)



    General Purpose Mobile Service. A mobile service that includes all 

mobile communications uses including those within the Aeronautical 

Mobile, Land Mobile, or the Maritime Mobile Services.

    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 geosynchronous 

satellite which remains approximately fixed relative to the Earth. (RR)

    Geostationary Satellite Orbit. The orbit in which a satellite must 

be placed to be a geostationary satellite. (RR)

    Geosynchronous Satellite. An Earth satellite whose period of 

revolution is equal to the period of rotation of the Earth about its 

axis. (RR)

    Government Master File (GMF). NTIA's database of Federal 

assignments. It also includes non-Federal authorizations coordinated 

with NTIA for the bands allocated for shared Federal and non-Federal 

use. (FCC)

    Harmful Interference. Interference which endangers the functioning 

of a radionavigation service or of other safety services or seriously 

degrades, obstructs, or repeatedly interrupts a radiocommunication 

service operating in accordance with [the ITU] Radio Regulations. (CS)

    High Altitude Platform Station (HAPS). A station located on an 

object at an altitude of 20 to 50 km and at a specified, nominal, fixed 

point relative to the Earth. (RR)

    Hybrid Spread Spectrum Systems. Hybrid spread spectrum systems are 

those



[[Page 531]]



which use combinations of two or more types of direct sequence, 

frequency hopping, time hopping and pulsed FM modulation in order to 

achieve their wide occupied bandwidths.

    Inclination of an Orbit (of an earth satellite). The angle 

determined by the plane containing the orbit and the plane of the 

Earth's equator measured in degrees between 0[deg] and 180[deg] and in 

counter-clockwise direction from the Earth's equatorial plane at the 

ascending node of the orbit. (RR)

    Individual Reception (in the broadcasting-satellite service). The 

reception of emissions from a space station in the broadcasting-

satellite service by simple domestic installations and in particular 

those possessing small antennae. (RR)

    Industrial, Scientific and Medical (ISM) (of radio frequency energy) 

Applications. Operation of equipment or appliances designed to generate 

and use locally radio-frequency energy for industrial, scientific, 

medical, domestic or similar purposes, excluding applications in the 

field of telecommunications. (RR)

    Instrument Landing System (ILS). A radionavigation system which 

provides aircraft with horizontal and vertical guidance just before and 

during landing and, at certain fixed points, indicates the distance to 

the reference point of landing. (RR)

    Instrument Landing System Glide Path. A system of vertical guidance 

embodied in the instrument landing system which indicates the vertical 

deviation of the aircraft from its optimum path of descent. (RR)

    Instrument Landing System Localizer. A system of horizontal guidance 

embodied in the instrument landing system which indicates the horizontal 

deviation of the aircraft from its optimum path of descent along the 

axis of the runway. (RR)

    Interdepartment Radio Advisory Committee (IRAC). A committee of the 

Federal departments, agencies, and administrations that advises NTIA in 

assigning frequencies to Federal radio stations and in developing and 

executing policies, programs, procedures, and technical criteria 

pertaining to the allocation, management, and use of the spectrum. The 

IRAC consists of a main committee, subcommittees, and several ad hoc 

groups that consider various aspects of spectrum management policy. The 

FCC serves as a member of the Frequency Assignment Subcommittee and as 

Liaison Representative on the main committee, all other subcommittees 

and ad hoc groups. (FCC)

    Interference. The effect of unwanted energy due to one or a 

combination of emissions, radiations, or inductions upon reception in a 

radiocommunication system, manifested by any performance degradation, 

misinterpretation, or loss of information which could be extracted in 

the absence of such unwanted energy. (RR)

    International Telecommunication Union (ITU). An international 

organization within the United Nations System where governments and the 

private sector coordinate global telecom networks and services. The ITU 

is headquartered in Geneva, Switzerland and its internet address is 

www.itu.int. (FCC)

    Inter-Satellite Service. A radiocommunication service providing 

links between artificial satellites. (RR)

    Ionospheric Scatter. The propagation of radio waves by scattering as 

a result of irregularities or discontinuities in the ionization of the 

ionosphere. (RR)

    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)

    Land Mobile-Satellite Service. A mobile-satellite service in which 

mobile earth stations are located on land. (RR)

    Land Mobile Service. A mobile service between base stations and land 

mobile stations, or between land mobile stations. (RR)

    Land Mobile Station. A mobile station in the land mobile service 

capable of surface movement within the geographical limits of a country 

or continent.



[[Page 532]]



    Land Station. A station in the mobile service not intended to be 

used while in motion. (RR)

    Left-Hand (or Anti-Clockwise) Polarized Wave. An elliptically or 

circularly-polarized wave, in fixed plane, normal to the direction of 

propagation, whilst looking in the direction of propagation, rotates 

with time in a left hand or anti-clockwise direction. (RR)

    Line A. Begins at Aberdeen, Washington running by great circle arc 

to the intersection of 48[deg] N., 120[deg] W., thence along parallel 

48[deg] N., to the intersection of 95[deg] W., thence by great circle 

arc through the southernmost point of Duluth, Minn., thence by great 

circle arc to 45[deg] N., 85[deg] W., thence southward along meridian 

85[deg] W., to its intersection with parallel 41[deg] N., thence along 

parallel 41[deg] N., to its intersection with meridian 82[deg] W., 

thence by great circle arc through the southernmost point of Bangor, 

Maine, thence by great circle arc through the southernmost point of 

Searsport, Maine, at which point it terminates. (FCC)

    Line B. Begins at Tofino, B.C., running by great circle arc to the 

intersection of 50[deg] N., 125[deg] W., thence along parallel 50[deg] 

N., to the intersection of 90[deg] W., thence by great circle arc to the 

intersection of 45[deg] N., 79[deg]30[min] W., thence by great circle 

arc through the northernmost point of Drummondville, Quebec (Lat. 

45[deg]52[min] N., Long 72[deg]30[min] W.), thence by great circle arc 

to 48[deg]30[min] N., 70[deg] W., thence by great circle arc through the 

northernmost point of Compbellton, N.B., thence by great circle are 

through the northernmost point of Liverpool, N.S., at which point it 

terminates. (FCC)

    Line C. Begins at the intersection of 70[deg] N., 144[deg] W., 

thence by great circle arc to the intersection of 60[deg] N., 143[deg] 

W., thence by great circle arc so as to include all of the Alaskan 

Panhandle. (FCC)

    Line D. Begins at the intersection of 70[deg] N., 138[deg] W., 

thence by great circle arc to the intersection of 61[deg]20[min] N., 

139[deg] W. (Burwash Landing), thence by great circle arc to the 

intersection of 60[deg]45[min] N., 135[deg] W., thence by great circle 

arc to the intersection of 56[deg] N., 128[deg] W., thence south along 

128[deg] meridian to Lat. 55[deg] N., thence by great circle arc to the 

intersection of 54[deg] N., 130[deg] W., thence by great circle arc to 

Port Clements, thence to the Pacific Ocean where it ends. (FCC)

    Maritime Mobile-Satellite Service. A mobile-satellite service in 

which mobile earth stations are located on board ships; survival craft 

stations and emergency position-indicating radiobeacon stations may also 

participate in this service. (RR)

    Maritime Mobile Service. A mobile service between coast stations and 

ship stations, or between ship stations, or between associated on-board 

communication stations; survival craft stations and emergency position-

indicating radiobeacon stations may also participate in this service. 

(RR)

    Maritime Radionavigation-Satellite Service. A radionavigation-

satellite service in which earth stations are located on board ships. 

(RR)

    Maritime Radionavigation Service. A radionavigation service intended 

for the benefit and for the safe operation of ships. (RR)

    Marker Beacon. A transmitter in the aeronautical radionavigation 

service which radiates vertically a distinctive pattern for providing 

position information to aircraft. (RR)

    Mean Power (of a radio transmitter). The average power supplied to 

the antenna transmission line by a transmitter during an interval of 

time sufficiently long compared with the lowest frequency encountered in 

the modulation taken under normal operating conditions. (RR)

    Meteorological Aids Service. A radiocommunication service used for 

meteorological, including hydrological, observation and exploration. 

(RR)

    Meteorological-Satellite Service. An earth exploration-satellite 

service for meteorological purposes. (RR)

    Mobile Earth Station. An earth station in the mobile-satellite 

service intended to be used while in motion or during halts at 

unspecified points. (RR)

    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.





[[Page 533]]





    Note: This service may also include feeder links necessary for its 

operation. (RR)



    Mobile Service. A radiocommunication service between mobile and land 

stations, or between mobile stations. (CV)

    Mobile Station. A station in the mobile service intended to be used 

while in motion or during halts at unspecified points. (RR)

    Multi-Satellite Link. A radio link between a transmitting earth 

station and a receiving earth station through two or more satellites, 

without any intermediate earth station.



    Note: A multisatellite link comprises one up-link, one or more 

satellite-to-satellite links and one down-link. (RR)



    National Telecommunications and Information Administration (NTIA). 

An agency of the United States Department of Commerce that serves as the 

President's principal advisor on telecommunications and information 

policy issues. NTIA manages Federal use of the radio spectrum and 

coordinates Federal use with the FCC. NTIA sets forth regulations for 

Federal use of the radio spectrum within its Manual of Regulations & 

Procedures for Federal Radio Frequency Management (NTIA Manual). (FCC)

    Necessary Bandwidth. For a given class of emission, the width of the 

frequency band which is just sufficient to ensure the transmission of 

information at the rate and with the quality required under specified 

conditions. (RR)



    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.

    Occupied Bandwidth. The width of a frequency band such that, below 

the lower and above the upper frequency limits, the mean powers emitted 

are each equal to a specified percentage Beta/2 of the total mean power 

of a given emission.



    Note: Unless otherwise specified by the CCIR for the appropriate 

class of emission, the value of Beta/2 should be taken as 0.5%. (RR)



    On-Board Communication Station. A low-powered mobile station in the 

maritime mobile service intended for use for internal communications on 

board a ship, or between a ship and its lifeboats and life-rafts during 

lifeboat drills or operations, or for communication within a group of 

vessels being towed or pushed, as well as for line handling and mooring 

instructions. (RR)

    Orbit. The path, relative to a specified frame of reference, 

described by the centre of mass of a satellite or other object in space 

subjected primarily to natural forces, mainly the force of gravity. (RR)

    Out-of-band domain (of an emission). The frequency range, 

immediately outside the necessary bandwidth but excluding the spurious 

domain, in which out-of-band emissions generally predominate. Out-of-

band emissions, defined based on their source, occur in the out-of-band 

domain and, to a lesser extent, in the spurious domain. Spurious 

emissions likewise may occur in the out-of-band domain as well as in the 

spurious domain. (RR)

    Out-of-band Emission. Emission on a frequency or frequencies 

immediately outside the necessary bandwidth which results from the 

modulation process, but excluding spurious emissions. (RR)

    Passive Sensor. A measuring instrument in the earth exploration-

satellite service or in the space research service by means of which 

information is obtained by reception of radio waves of natural origin. 

(RR)

    Peak Envelope Power (of a radio transmitter). The average power 

supplied to the antenna transmission line by a transmitter during one 

radio frequency cycle at the crest of the modulation envelope taken 

under normal operating conditions. (RR)

    Period (of a satellite). The time elapsing between two consecutive 

passages of a satellite through a characteristic point on its orbit. 

(RR)

    Permissible Interference.\3\ Observed or predicted interference 

which complies with quantitative interference and sharing criteria 

contained in these [ITU Radio] Regulations or in ITU-R



[[Page 534]]



Recommendations or in special agreements as provided for in these 

Regulations. (RR)

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    \3\ See footnote under Accepted Interference.

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    Port Operations Service. A maritime mobile service in or near a 

port, between coast stations and ship stations, or between ship 

stations, in which messages are restricted to those relating to the 

operational handling, the movement and the safty of ships and, in 

emergency, to the safety of persons.



    Note: Messages which are of a public correspondence nature shall be 

excluded from this service. (RR)



    Port Station. A coast station in the port operations service. (RR)

    Power. Whenever the power of a radio transmitter, etc. is referred 

to it shall be expressed in one of the following forms, according to the 

class of emission, using the arbitrary symbols indicated:

    (1) Peak envelope power (PX or pX);

    (2) Mean power (PY or pY);

    (3) Carrier power (PZ or pZ).



    Note 1: For different classes of emission, the relationships between 

peak envelope power, mean power and carrier power, under the conditions 

of normal operation and of no modulation, are contained in ITU-R 

Recommendations which may be used as a guide.

    Note 2: For use in formulae, the symbol p denotes power expressed in 

watts and the symbol P denotes power expressed in decibels relative to a 

reference level. (RR)



    Primary Radar. A radiodetermination system based on the comparison 

of reference signals with radio signals reflected from the position to 

be determined. (RR)

    Protection Ratio. The minimum value of the wanted-to-unwanted signal 

ratio, usually expressed in decibels, at the receiver input determined 

under specified conditions such that a specified reception quality of 

the wanted signal is achieved at the receiver output. (RR)

    Public Correspondence. Any telecommunication which the offices and 

stations must, by reason of their being at the disposal of the public, 

accept for transmission. (CS)

    Pulsed FM Systems. A pulsed FM system is a spread spectrum system in 

which a RF carrier is modulated with a fixed period and fixed duty cycle 

sequence. At the beginning of each transmitted pulse, the carrier 

frequency is frequency modulated causing an additional spreading of the 

carrier. The pattern of the frequency modulation will depend upon the 

spreading function which is chosen. In some systems the spreading 

function is a linear FM chirp sweep, sweeping either up or down in 

frequency.

    Radar. A radiodetermination system based on the comparison of 

reference signals with radio signals reflected, or retrainsmitted, from 

the position to be determined. (RR)

    Radar Beacon (RACON). A transmitter-receiver associated with a fixed 

navigational mark which, when triggered by a radar, automatically 

returns a distinctive signal which can appear on the display of the 

triggering radar, providing range, bearing and identification 

information. (RR)

    Radiation. The outward flow of energy from any source in the form of 

radio waves. (RR)

    Radio. A general term applied to the use of radio waves. (RR)

    Radio Altimeter. Radionavigation equipment, on board an aircraft or 

spacecraft or the spacecraft above the Earth's surface or another 

surface. (RR)

    Radio Astronomy. Astronomy based on the reception of radio waves of 

cosmic origin. (RR)

    Radio Astronomy Service. A service involving the use of radio 

astronomy. (RR)

    Radio Astronomy Station. A station in the radio astronomy service. 

(RR)

    Radiobeacon Station. A station in the radionavigation service the 

emissions of which are intended to enable a mobile station to determine 

its bearing or direction in relation to radiobeacon station. (RR)

    Radiocommunication. Telecommunication by means of radio waves. (CS) 

(CV)

    Radiocommunication Service. A service as defined in this Section 

involving the transmission, emission and/or reception of radio waves for 

specific telecommunication purposes.



    Note: In these [international] Radio Regulations, unless otherwise 

stated, any radiocommunication service relates to terrestrial 

radiocommunication. (RR)



    Radiodetermination. The determination of the position, velocity and/

or



[[Page 535]]



other characteristics of an object, or the obtaining of information 

relating to these parameters, by means of the propagation properties of 

radio waves. (RR)

    Radiodetermination-Satellite Service. A radiocommunication service 

for the purpose of radiodetermination involving the use or one of more 

space stations. This service may also include feeder links necessary for 

its own operation. (RR)

    Radiodetermination Service. A radiocommunication service for the 

purpose of radiodetermination. (RR)

    Radiodetermination Station. A station in the radiodetermination 

serviice. (RR)

    Radio Direction-Finding. Radiodetermination using the reception of 

radio waves for the purpose of determining the direction of a station or 

object. (RR)

    Radio Direction-Finding Station. A radiodetermination station using 

radio direction-finding. (RR)

    Radiolocation. Radiodetermination used for purposes other than those 

of radionavigation. (RR)

    Radiolocation Land Station. A station in the radiolocation service 

not intended to be used while in motion. (RR)

    Radiolocation Mobil Station. A station in the radiolocation service 

intended to be used while in motion or during halts at unspecified 

points. (RR)

    Radiolocation Service. A radiodetermination service for the purpose 

of radiolocation. (RR)

    Radionavigation. Radiodetermination used for the purposes of 

navigation, including obstruction warning.

    Radionavigation Land Station. A station in the radionavigation 

service not intended to be used while in motion. (RR)

    Radionavigation Mobile Station. A station in the radionavigation 

service intended to be used while in motion or during halts at 

unspecified points. (RR)

    Radionavigation-Satellite Service. A radiodetermination-satellite 

service used for the purpose of radionavigation. This service may also 

include feeder links necessary for its operation. (RR)

    Radionavigation Service. A radiod-etermination service for the 

purpose of radionavigation. (RR)

    Radiosonde. An automatic radio transmitter in the meteorological 

aids service usually carried on an aircraft, free ballon, kite or 

parachute, and which transmits meteorological data. (RR)

    Radiotelegram. A telegram, originating in or intended for a mobile 

station or a mobile earth station transmitted on all or part of its 

route over the radiocommunication channels of the mobile service or of 

the mobile-satellite service. (RR)

    Radiotelemetry. Telemetry by means of radio waves. (RR)

    Radiotelephone Call. A telephone call, originating in or intended 

for a mobile station or a mobile earth station, transmitted on all or 

part of its route over the radiocommunication channels of the mobile 

service or of the mobile-satellite service. (RR)

    Radiotelex Call. A telex call, originating in or intended for a 

mobile station or a mobile earth station, transmitted on all or part of 

its route over the radiocommunication channels of the mobile service or 

the mobile-satellite service. (RR)

    Radio Waves or Hertzian Waves. Electromagnetic waves of frequencies 

arbitrarily lower than 3,000 GHz, propagated in space without 

aritificial guide. (RR)

    Reduced Carrier Single-Sideband Emission. A single-sideband emission 

in which the degree of carrier suppession enables the carrier to be 

reconstrituted and to be used for demodulation. (RR)

    Reference Frequency. A frequency having a fixed and specified 

position with respect to the assigned frequency. The displacement of 

this frequency with respect to the assigned frequency has the same 

absolute value and sign that the displacement of the characteristic 

frequency has with respect to the centre of the frequency band occupied 

by the emission. (RR)

    Reflecting Satellite. A satellite intended to reflect 

radiocommunication signals. (RR)

    Right-Hand (or Clockwise) Polarized Wave. An Elliptically or 

circularly-polarized wave, in which the electric field vector, observed 

in any fixed plane, normal to the direction of propagation,



[[Page 536]]



whilst looking in the direction of propagation, rotates with time in a 

right-hand or clockwise direction. (RR)

    Safety Service. Any radiocommunication service used permanently or 

temporarily for the safeguarding of human life and property. (RR)

    Satellite. A body which revolves around another body of preponderant 

mass and which has a motion primarily and permanently determined by the 

force of attraction of that other body. (RR)

    Satellite Link. A radio link between a transmitting earth station 

and a receiving earth station through one satellite. A satellite link 

comprises one up-link and one down-link. (RR)

    Satellite Network. A satellite system or a part of a satellite 

system, consisting of only one satellite and the cooperating earth 

stations. (RR)

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

satellites. (RR)

    Secondary Radar. A radiodetermination system based on the comparison 

of reference signals with radio signals retransmitted from the position 

to be determined. (RR)

    Semi-Duplex Operation.\4\ A method which is simplex operation on one 

end of the circuit and duplex operation at the other. (RR)

    Simplex Operation.\4\ Operating method in which transmission is made 

possible alternatively in each direction of a telecommunication channel, 

for example, by means of manual control.

---------------------------------------------------------------------------



    \4\ See footnote under Duplex Operation.

---------------------------------------------------------------------------



    Ship Earth Station. A mobile earth station in the maritime mobile-

satellite service located on board ship. (RR)

    Ship Movement Service. A safety service in the maritime mobile 

service other than a port operations service, between coast stations and 

ship stations, or between ship stations, in which messages are 

restricted to those relating to the movement of ships. Messages which 

are of a public correspondence nature shall be excluded from this 

service. (RR)

    Ship's Emergency Transmitter. A ship's transmitter to be used 

exclusively on a distress frequency for distress, urgency or safety 

purposes. (RR)

    Ship Station. A mobile station in the maritime mobile service 

located on board a vessel which is not permanently moored, other than a 

survival craft station. (RR)

    Simplex Operation. Operating method in which transmission is made 

possible alternatively in each direction of a telecommunication channel, 

for example, by means of manual control. \5\ (RR)

---------------------------------------------------------------------------



    \5\ (See footnote under Duplex Operations.)

---------------------------------------------------------------------------



    Single-Sideband Emission. An amplitude modulated emission with one 

sideband only. (RR)

    Software defined radio. A radio that includes a transmitter in which 

the operating parameters of frequency range, modulation type or maximum 

output power (either radiated or conducted), or the circumstances under 

which the transmitter operates in accordance with Commission rules, can 

be altered by making a change in software without making any changes to 

hardware components that affect the radio frequency emissions.

    Spacecraft. A man-made vehicle which is intended to go beyond the 

major portion of the Earth's atmosphere. (RR)

    Space Operation Service. A radiocommunication service concerned 

exclusively with the operation of spacecraft, in particular space 

tracking, space telemetry, and space telecommand.



    Note: These functions will normally be provided within the service 

in which the space station is operating. (RR)



    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. (RR)

    Space Research Service. A radiocommunication service in which 

spacecraft or other objects in space are used for scientific or 

technological research purposes. (RR)

    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. (RR)



[[Page 537]]



    Space System. Any group of cooperating Earth stations and/or space 

stations employing space radiocommunication for specific purposes. (RR)

    Space Telecommand. The use of radiocommunication for the 

transmission of signals to a space station to initiate, modify or 

terminate functions of equipment on a space object, incuding the space 

station. (RR)

    Space Telemetry. The use of telemetry for transmission for a space 

station of results of measurements made in a spacecraft, including those 

relating to the functioning of the spacecraft. (RR)

    Space Tracking. Determination of the orbit, velocity or 

instanteneous position of an object in space by means of 

radiodetermination, excluding primary radar, for the purpose of 

following the movement of the object. (RR)

    Special Service. A radiocommunication service, not otherwise defined 

in this Section, carried on exclusively for specific needs of general 

utility, and not open to public correspondence. (RR)

    Spread Spectrum Systems. A spread spectrum system is an information 

bearing communications system in which: (1) Information is conveyed by 

modulation of a carrier by some conventional means, (2) the bandwidth is 

deliberately widened by means of a spreading function over that which 

would be needed to transmit the information alone. (In some spread 

spectrum systems, a portion of the information being conveyed by the 

system may be contained in the spreading function.)

    Spurious domain (of an emission): The frequency range beyond the 

out-of-band domain in which spurious emissions generally predominate. 

(RR)

    Spurious Emission. Emission on a frequency or frequencies which are 

outside the necessary bandwidth and the level of which may be reduced 

without affecting the corresponding transmission of information. 

Spurious emissions include harmonic emissions, parasitic emissions, 

intermodulation products and frequency conversion products, but exclude 

out-of-band emissions. (RR)

    Standard Frequency and Time Signal-Satellite Service. A 

radiocommunication service using space stations on earth satellites for 

the same purposes as those of the standard frequency and time signal 

service.



    Note: This service may also include feeder links necessary for its 

operation. (RR)



    Standard Frequency and Time Signal Service. A radiocommunication 

service for scientific, technical and other purposes, providing the 

transmission of specified frequencies, time signals, or both, of stated 

high precision, intended for general reception. (RR)

    Standard Frequency and Time Signal Station. A station in the 

standard frequency and time signal service. (RR)

    Station. One or more transmitters or receivers or a combination of 

transmitters and receivers, including the accessory equipment, necessary 

at one location for carrying on a radiocommunication service, or the 

radio astronomy service.



    Note: Each station shall be classified by the service in which it 

operates permanently or temporarily. (RR)



    Suppressed Carrier Single-Sideband Emission. A single-sideband 

emission in which the carrier is virtually suppressed and not intended 

to be used for demodulation. (RR)

    Survival Craft Station. A mobile station in the maritime mobile 

service or the aeronautical mobile service intended solely for survival 

purposes and located on any lifeboat, life-raft or other survival 

equipment. (RR)

    Telecommand. The use of telecommunication for the transmission of 

signals to initiate, modify or terminate functions of equipment at a 

distance. (RR)

    Telecommunication. Any transmission, emission or reception of signs, 

signals, writings, images and sounds or intelligence of any nature by 

wire, radio, optical or other electromagnetic systems. (CS)

    Telegram. Written matter intended to be transmitted by telegraphy 

for delivery to the addressee. This term also includes radiotelegrams 

unless otherwise specified. (CS)

    Note: In this definition the term telegraphy has the same general 

meaning as defined in the Convention.



[[Page 538]]



    Telegraphy.\5\ A form of telecommunication in which the transmitted 

information is intended to be recorded on arrival as a graphic document; 

the transmitted information may sometimes be presented in an alternative 

form or may be stored for subsequent use. (CS)

---------------------------------------------------------------------------



    \5\ A graphic document records information in a permanent form and 

is capable of being filed and consulted; it may take the form of written 

or printed matter or of a fixed image.

---------------------------------------------------------------------------



    Telemetry. The use of telecommunication for automatically indicating 

or recording measurements at a distance from the measuring instrument. 

(RR)

    Telephony. A form of telecommunication primarily intended for the 

exchange of information in the form of speech. (CS)

    Television. A form of telecommunication for the transmission of 

transient images of fixed or moving objects. (RR)

    Terrestrial Radiocommunication. Any radiocommunication other than 

space radiocommunication or radio astronomy. (RR)

    Terrestrial Station. A station effecting terrestrial 

radiocommunication.



    Note: In these [international Radio] Regulations, unless otherwise 

stated, any station is a terrestrial station. (RR)



    Time Hopping Systems. A time hopping system is a spread spectrum 

system in which the period and duty cycle of a pulsed RF carrier are 

varied in a pseudorandom manner under the control of a coded sequence. 

Time hopping is often used effectively with frequency hopping to form a 

hybrid time-division, multiple-access (TDMA) spread spectrum system.

    Transponder. A transmitter-receiver facility the function of which 

is to transmit signals automatically when the proper interrogation is 

received. (FCC)

    Tropospheric Scatter. The propagation of radio waves by scattering 

as a result of irregularities or discontinuities in the physical 

properties of the troposphere. (RR)

    Unwanted Emissions. Consist of spurious emissions and out-of-band 

emissions. (RR)



[49 FR 2368, Jan. 19, 1984, as amended at 50 FR 25239, June 18, 1985; 51 

FR 37399, Oct. 22, 1986; 52 FR 7417, Mar. 11, 1987; 54 FR 49980, Dec. 4, 

1990; 55 FR 28761, July 13, 1990; 56 FR 42703, Aug. 29, 1991; 58 FR 

68058, Dec. 23, 1993; 62 FR 26242, May 13, 1997; 65 FR 60109, Oct. 10, 

2000; 66 FR 50840, Oct. 5, 2001; 68 FR 74330, Dec. 23, 2003; 70 FR 

23039, May 4, 2005; 70 FR 46583, Aug. 10, 2005; 71 FR 15619, Mar. 29, 

2006]