Radiation HardeningProtection of a particular system, subsystem, or component from functional damage due to the effects of nuclear (or other) radiation by shielding the…
radiation modeFor an optical fiber, an unbound mode. Note: In an optical fiber, a radiation mode is one having fields that are transversely oscillatory everywhere…
radiation patternThe variation of the field intensity of an antenna as an angular function with respect to the axis.
radiation resistanceThe resistance that, if inserted in place of an antenna, would consume the same amount of power that is radiated by the antenna.
radiation scatteringThe diversion of radiation (thermal, electromagnetic, or nuclear) from its original path as a result of interaction or collisions with atoms, molecules…
radiation-hardened fiberAn optical fiber made with core and cladding materials that recover, within a specified period of time, a specified percentage of their intrinsic…
RADIC SystemRapidly Deployable Integrated Command and Control System.
radio1. Telecommunication by modulation and radiation of electromagnetic waves. 2. A transmitter, receiver, or transceiver used for communication via…
radio access system controllerA controller that supports the wireless mobility management and wireless access call control functions.
radio altimeterRadionavigation 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 beamA 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 Blackout (RBO)The complete disruption of radio (or radar) signal over large areas caused by the ionization accompanying a high altitude nuclear explosion, especially…
radio buttonsA group of selectable components in which only one component may be selected. Selection of one of the group causes the previously selected component to be…
radio channelAn 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 privacyAn 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 controlThe remote control of an apparatus by signals conveyed by electromagnetic waves.
radio detectionThe detection of the presence of an object by radiolocation without precise determination of its position. [JP 1-02]
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 equipmentAs defined in Federal Information Management Regulations, any equipment or interconnected system or subsystem of equipment (both transmission and…
radio facilityThe bearer/signaling connection between the radio port intermediary and the radio port controller. [T1.Rpt34-1994]
radio fixThe 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 horizonThe 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 interfaceThe common boundary between a mobile station and the radio equipment in the network, which is the boundary defined by functional characteristics, physical…
radio netAn organization of radio stations that is capable of direct communication on a common frequency. 2.
radio pagingThe 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 portA unit that supports transmission of signals over the air interface. [After T1.Rpt34-1994]
radio port controllerA controller that provides an interface between one or more subtending radio port intermediaries and a PCS switching center, and supports air interface…
radio rangeThe 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 stationA radionavigation land station in the aeronautical radionavigation service providing radial equisignal zones.
Radio RegulationsAs 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 BoardA permanent organization of the International Telecommunication Union (ITU) that implements frequency assignment policy and maintains the Master…
radio relayThe 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 systemA point-to-point radio transmission system in which signals are received, conditioned, and retransmitted by one or more intermediate radio stations.
radio telegraphyThe transmission of telegraphic codes by means of radio. [JP 1-02]
radio telephonyThe 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 waveAn electromagnetic wave of a frequency arbitrarily lower than 3000 GHz. Synonym Hertzian wave.
radio-coverage diagramA diagram that shows the area within which a radio station is broadcasting an effective signal strength in relation to a given standard.
Radioactive (or Nuclear) CloudAn all-inclusive term for the volume of hot gases, smoke, dust, and other particulate matter from the nuclear weapon itself and from its environment, that…
RadioactivityThe spontaneous decay of disintegration of an unstable atomic nucleus accompanied by the emission of radiation.
radiobeacon stationA station in the radionavigation service the emissions of which are intended to enable a mobile station to determine its bearing or direction in relation…
radiocommunicationTelecommunication by means of radio waves. [NTIA] [RR] [47CFR]
radiocommunication serviceA service as defined in this Section [of the Radio Regulations] involving the transmission, emission and/or reception of radio waves for specific…
radiodeterminationThe determination of the position, velocity and/or other characteristics of an object, or the obtaining of information relating to these parameters, by…
radiodetermination-satellite serviceA radiocommunication service for the purpose of radiodetermination involving the use of one or more space stations.
radiolocationRadiodetermination used for purposes other than those of radionavigation. [NTIA] [RR] [47CFR]
radiolocation land stationA station in the radiolocation service not intended to be used while in motion. [NTIA] [RR] [47CFR]
radiolocation mobile stationA station in the radiolocation service intended to be used while in motion or during halts at unspecified points. [NTIA] [RR] 2.
radiolocation serviceA radiodetermination service for the purpose of radiolocation. [NTIA] [RR]
radiometryThe science of radiation measurement. See Table of Radiometric Terms. TABLE OF RADIOMETRIC TERMS Term Symbol Quantity Unit radiant energy Q energy joule…
radionavigationRadiolocation intended for the determination of position or direction or for obstruction warning in navigation. [JP 1-02] 2.
radionavigation land stationA station in the radionavigation service not intended to be used while in motion. [NTIA] [RR]
radionavigation mobile stationA station in the radionavigation service intended to be used while in motion or during halts at unspecified points. [NTIA] [RR]
radionavigation-satellite serviceA radiodetermination-satellite service used for the purpose of radionavigation. This service may also include feeder links necessary for its operation.
RadiosondeAn instrument that is carried aloft by a balloon to send back information on atmospheric temperature, pressure and humidity by means of a small…
radiotelegramA 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…
radiotelemetryTelemetry by means of radio waves. [NTIA] [RR]
radiotelephone callA 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…
radiotelephone distress frequencyAn international distress and calling frequency for mobile radiotelephone stations, survival craft, and emergency position-indicating radio beacons.
radiotelex callA 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…
RADIUSHorizontal distance from the center of rotation.
RAIDA raid is a large-scale attack on an area by a group of players.
RAID (Redundant Array of Independent Disk)Redundant Array of Inexpensive Disks. A technology in which data is stored in distributed fashion across multiple disk drives to achieve redundancy and…
RAID (Redundant Array of Independent Disks)A method of accessing multiple individual disks as if the array were one larger disk, spreading data access out over these multiple disks.
RAID (Redundant Arrays of Independent Disks)A way of storing the same data in different places on multiple hard disks. Storing data on multiple disks can improve performance by balancing input and…
RAID 0 (striped disks without parity)Block striping across multiple drives is provided, yielding higher performance than is possible with individual drives.
RAID 1 (mirrored disks without parity)Provides data protection by duplicating all data from a primary drive on a secondary drive. Drives are paired and mirrored.
RAID disk scrubbingThe process by which the system reads each disk in the RAID group and tries to fix media errors by rewriting the data to another disk area.