Telecommunications terms starting with R

465 terms

R interface For a basic rate access in an ISDN environment, the interfacing specifications covering pre-ISDN standards (e.g., EIA-232C).
R/C Abbreviation for radio control, radio service.
raceway Within a building, an enclosure, i.e., channel, used to contain and protect wires, cables, or bus bars.
rack A frame upon which one or more units of equipment are mounted. Note: DOD racks are always vertical.
racon See radar beacon.
RAD Radiation Absorbed Dose. The basic unit of an absorbed dose of ionizing radiation.
radar Acronym for RAdio Detection And Ranging; a radio device or system for locating an object by means of ultrahigh-frequency radio waves reflected from the…
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…
radar blind range The range that corresponds to the situation in which a radar transmitter is on and hence the receiver must be off, so that the radar transmitted signal…
radar blind speed The magnitude of the radial component of velocity of an object, i.e., a target, relative to a radar site, that cannot be measured by the radar unit.
Radar Cross Section The area of a fictitious, perfect reflector of electromagnetic waves (e.g., metal sphere) that would reflect the same amount of energy back to the radar…
radar intelligence (RADINT) Intelligence derived from data collected by radar. [JP 1-02]
radar mile The time required for a radar pulse to travel 1 mile (~1.6 km) to an object, i.e., to a target; reflect; and return to the receiver.
radar resolution cell The volume of space that is occupied by a radar pulse and that is determined by the pulse duration and the horizontal and vertical beamwidths of the…
radar signature 1. The detailed waveform of a detected radar echo. Note: Radar signatures may be used to identify or distinguish among objects, i.e.
radar xxline-of-sight (LOS) equation An equation that expresses the radar horizon range (RHR), given by where RHRs is the radar horizon range in statute miles, h is the antenna height in…
RADHAZ (1) Electromagnetic Radiation Hazard. (2) Hazards form electromagnetic radiation.
radian (rad.) A unit of plane angle measure equal to the angle subtended at the center of a circle by an arc equal in length to the radius of the circle.
radiance A measure of the intensity of the radiant energy flux emitted by a body in a given direction.
radiant emittance Radiant power emitted into a full sphere, i.e., 4 sr (steradians), by a unit area of a source, expressed in watts per square meter.
Radiant Energy Energy that transmits away from its source in all directions.
radiant exitance Synonym radiant emittance.
radiant flux Deprecated synonym for radiant power.
radiant intensity Radiant power per unit solid angle, usually expressed in watts per steradian.
radiant power The rate of flow of electromagnetic energy, i.e., radiant energy. Note 1: Radiant power is usually expressed in watts, i.e., joules per second.
Radiation (RAY-dee-AY-shun) Energy released in the form of particle or electromagnetic waves.
radiation angle In fiber optics, half the vertex angle of the cone of light emitted at the exit face of an optical fiber.
radiation efficiency At a given frequency, the ratio of the power radiated to the total power supplied to the radiator.
radiation field Synonym far-field region.
radiation mode For an optical fiber, an unbound mode. Note: In an optical fiber, a radiation mode is one having fields that are transversely oscillatory everywhere…
radiation pattern The variation of the field intensity of an antenna as an angular function with respect to the axis.
radiation resistance The resistance that, if inserted in place of an antenna, would consume the same amount of power that is radiated by the antenna.
radiation scattering The diversion of radiation (thermal, electromagnetic, or nuclear) from its original path as a result of interaction or collisions with atoms, molecules…
radiation security Measures to defend against TEMPEST attacks [CESG].
radiation-hardened fiber An optical fiber made with core and cladding materials that recover, within a specified period of time, a specified percentage of their intrinsic…
RADINT Radar Intelligence.
radio 1. Telecommunication by modulation and radiation of electromagnetic waves. 2. A transmitter, receiver, or transceiver used for communication via…
radio access system controller A controller that supports the wireless mobility management and wireless access call control functions.
radio altimeter Radionavigation equipment, on board an aircraft or spacecraft, used to determine the height of the aircraft or the spacecraft above the Earth's surface or…
radio and wire integration (RWI) The combining of wire circuits with radio facilities. [JP 1-02]
radio baseband See baseband.
radio beam A radiation pattern from a directional antenna, such that the energy of the transmitted electromagnetic wave is confined to a small angle in at least one…
radio channel An assigned band of frequencies sufficient for radio communication. Note 1: The bandwidth of a radio channel depends upon the type of transmission and the…
radio channel privacy An encryption treatment applied to signaling or user data, which treatment is intended to prevent an unauthorized detector of the data from extracting…
radio common carrier (RCC) A telecommunications common carrier that provides radio communications services but is not engaged in the business of providing landline local exchange…
radio control The remote control of an apparatus by signals conveyed by electromagnetic waves.
radio detection The detection of the presence of an object by radiolocation without precise determination of its position. [JP 1-02]
radio detection and ranging See radar.
radio direction-finding [RDF] Radiodetermination using the reception of radio waves for the purpose of determining the direction of a station or object. [NTIA] [RR]
radio direction-finding station A radiodetermination station using radio direction-finding. [NTIA] [RR]
radio equipment As defined in Federal Information Management Regulations, any equipment or interconnected system or subsystem of equipment (both transmission and…
radio facility The bearer/signaling connection between the radio port intermediary and the radio port controller. [T1.Rpt34-1994]
radio fadeout See flutter.
radio field intensity Synonym field strength.
radio fix The locating of a radio transmitter by bearings taken from two or more direction finding stations, the site of the transmitter being at the point of…
radio frequency See RF.
radio frequency assignment See frequency assignment.
radio frequency channel assignment Synonym frequency assignment.
radio frequency interference (RFI) Synonym electromagnetic interference.
radio horizon The locus of points at which direct rays from an antenna are tangential to the surface of the Earth.
radio horizon range (RHR) The distance at which a direct radio wave can reach a receiving antenna of given height from a transmitting antenna of given height.
radio interface The common boundary between a mobile station and the radio equipment in the network, which is the boundary defined by functional characteristics, physical…
radio net An organization of radio stations that is capable of direct communication on a common frequency. 2.
radio paging The use of a pocket-size radio receiver capable of alerting its wearer that there is a phone call, either from a displayed phone number or to a…
radio personal terminal (RPT) A light-weight, pocket-size portable radio terminal (or "personal terminal") providing the capability for the user to be either stationary or in motion…
radio port A unit that supports transmission of signals over the air interface. [After T1.Rpt34-1994]
radio port controller A controller that provides an interface between one or more subtending radio port intermediaries and a PCS switching center, and supports air interface…
radio range The distance from a transmitter at which the signal strength remains above the minimum usable level for a particular antenna and receiver combination. 2.
radio range station A radionavigation land station in the aeronautical radionavigation service providing radial equisignal zones.
radio recognition and identification See identification, friend or foe.
Radio Regulations As used in legal documents, the latest (i.e., as of the document date) ITU Radio Regulations to which the United States is a party.
Radio Regulations Board A permanent organization of the International Telecommunication Union (ITU) that implements frequency assignment policy and maintains the Master…
radio relay The reception and retransmission by a radio station of signals that are received either from another radio station or from a wire, fiber optic, microwave…
radio relay system A point-to-point radio transmission system in which signals are received, conditioned, and retransmitted by one or more intermediate radio stations.
radio telegraphy The transmission of telegraphic codes by means of radio. [JP 1-02]
radio telephony The transmission of speech by means of modulated radio waves. [JP 1-02]
radio teletypewriter (RTTY) A teletypewriter employed in a communication system using radio circuits. Note: Such systems are spoken of as RATT systems.
radio termination (RT) A device or functionality that terminates radio transmissions, performs radio channel management, provides rate adaptation between the radio channel and…
radio watch shift Synonym area broadcast shift.
radio wave An electromagnetic wave of a frequency arbitrarily lower than 3000 GHz. Synonym Hertzian wave.
radio-coverage diagram A diagram that shows the area within which a radio station is broadcasting an effective signal strength in relation to a given standard.
radio-wire integration See radio and wire integration.
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…
radiocommunication Telecommunication by means of radio waves. [NTIA] [RR] [47CFR]
radiocommunication service A service as defined in this Section [of the Radio Regulations] involving the transmission, emission and/or reception of radio waves for specific…
radiodetermination The determination of the position, velocity and/or other characteristics of an object, or the obtaining of information relating to these parameters, by…
radiodetermination station A station in the radiodetermination service. [NTIA] [RR]
radiodetermination-satellite service A radiocommunication service for the purpose of radiodetermination involving the use of one or more space stations.
radiolocation Radiodetermination used for purposes other than those of radionavigation. [NTIA] [RR] [47CFR]
radiolocation land station A station in the radiolocation service not intended to be used while in motion. [NTIA] [RR] [47CFR]
radiolocation mobile station A station in the radiolocation service intended to be used while in motion or during halts at unspecified points. [NTIA] [RR] 2.
radiolocation service A radiodetermination service for the purpose of radiolocation. [NTIA] [RR]
radiological monitoring Synonym monitoring.
radiometry The science of radiation measurement. See Table of Radiometric Terms. TABLE OF RADIOMETRIC TERMS Term Symbol Quantity Unit radiant energy Q energy joule…
radionavigation Radiolocation intended for the determination of position or direction or for obstruction warning in navigation. [JP 1-02] 2.
radionavigation land station A station in the radionavigation service not intended to be used while in motion. [NTIA] [RR]
radionavigation mobile station A station in the radionavigation service intended to be used while in motion or during halts at unspecified points. [NTIA] [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.
Radiosonde An instrument that is carried aloft by a balloon to send back information on atmospheric temperature, pressure and humidity by means of a small…
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…