Glossary of Terms
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
A RF power amplifier is a type of electronic amplifier used to convert a low-power radio-frequency signal into a larger signal of significant power, typically for driving the antenna of a transmitter. It is usually optimized to have high efficiency, high P1dB compression, good return loss on the input and output, good gain, and good heat dissipation.
Twisted pair cabling is a form of wiring in which two conductors are wound together for the purposes of canceling out electromagnetic interference (EMI) from external sources; for instance, electromagnetic radiation from unshielded twisted pair (UTP) cables, and crosstalk between neighboring pairs.
is an electrical cable consisting of an inner conductor or several uninsulated conductors tightly twisted together, often surrounded by an insulating spacer, surrounded by an outer cylindrical conducting shield (sheath), and usually surrounded by a final insulating layer (jacket). The term coaxial comes from the inner conductor and the outer shield sharing (“co-“) the same axis. It is often used as a high-frequency transmission line to carry a high-frequency or broadband signal but may also be used for frequencies as low as audio frequency.
DVB, short for Digital Video Broadcasting, is a suite of internationally accepted open standards for digital television. DVB standards are maintained by the DVB Project, an industry consortium with more than 270 members, and they are published by a Joint Technical Committee (JTC) of European Telecommunications Standards Institute (ETSI), European Committee for Electrotechnical Standardization (CENELEC) and European Broadcasting Union (EBU). The interaction of the DVB sub-standards is described in the DVB Cookbook (DVB-Cook).
is the abbreviation of erbium-doped fiber amplifier. It is a kind of laser amplifier and it is the most deployed fiber amplifier as its amplification window coincides with the third transmission window of silica-based optical fiber. EDFAs have two commonly-used pumping bands – 980 nm and 1480 nm. The 980 nm band has a higher absorption cross-section and is generally used where low-noise performance is required. The absorption band is relatively narrow and so wavelength stabilized laser sources are typically needed. The 1480 nm band has a lower, but broader, absorption cross-section and is generally used for higher power amplifiers. A combination of 980 nm and 1480 nm pumping is generally utilized in amplifiers.
A switch is a mechanical device used to connect and disconnect a circuit at will. Switches cover a wide range of types, from subminiature up to industrial plant switching megawatts of power on high voltage distribution lines.
An adaptor is a device used to connect the same or different type connectors, so that a connection may be made between them.
Fiber Optic Cable
An fiber optic cable
is a cable containing one or more optical fibers. The optical fiber
elements are typically individually coated with plastic layers and contained in a protective tube suitable for the environment where the cable will be deployed.
Fiber Optic Closure
Fiber optic closure
, include horizontal and vertical type, is a device that is used to splice and jointing for optical fiber cables. They are commonly used in fiber optic communication system.
A patch cord is an optical cable, used to connect optical device to another for signal routing. Each end of the cable is attached to a connector, so the cord may be plugged in. Pigtail is a cable with one connector. Types of connectors may vary widely, FC, SC, ST, and etc.
Fiber Optic Termination Box
Fiber optic termination box
is used to terminate and connect optical fibers by splices and connectors. The boxes are wall mounted, or installed in the cabinet. They can be used with any type of connectors.
Fiber to the x (FTTX) including FTTH
, FTTB, FTTC and FTTN, is a generic term for any network architecture that uses optical fiber to replace all or part of the usual copper local loop used for telecommunications. FTTx is delivered using active Ethernet and various passive optical network (PON) technologies. The passive FTTx approach utilizes equipment that does not require power, and splits or divides the bandwidth between users.
Gigabit Ethernet Passive Optical Network(GEPON) is a point-to-multipoint, fiber to the premises network architecture in which unpowered optical splitters are used to enable a single optical fiber to serve multiple premises, typically 32.
Local Area Network (LAN) is a computer network covering a small geographic area, like a home, office, or group of buildings e.g. a school. The defining characteristics of LANs, in contrast to wide-area networks (WANs), include their much higher data-transfer rates, smaller geographic range, and lack of a need for leased telecommunication lines.
A fiber laser is a laser in which the active gain medium is an optical fiber doped with rare-earth elements such as erbium, ytterbium, neodymium, dysprosium, praseodymium, and thulium. They are related to doped fiber amplifiers, which provide light amplification without lasing. Fiber nonlinearities, such as stimulated Raman scattering or four-wave mixing can also provide gain and thus serve as gain media for a fiber laser.
An optical attenuator
is a device used to reduce the power level of an optical signal, either in free space or in an optical fiber. They are commonly used in fiber optic communications. The basic types of optical attenuators are fixed, step-wise variable, and continuously variable.
is passive optical device that connects three or more fiber ends, dividing one input between two or more outputs, or combining two or more inputs into one output. Optical coupler is generally deployed in passive optical network.
The main component of an optical receiver
is a photodetector that converts light into electricity through the photoelectric effect. The photodetector is typically a semiconductor-based photodiode, such as a p-n photodiode, a p-i-n photodiode, or an avalanche photodiode. Metal-semiconductor-metal (MSM) photodetectors are also used due to their suitability for circuit integration in regenerators and wavelength-division multiplexers.
The most commonly-used optical transmitters
are semiconductor devices such as light-emitting diodes (LEDs) and laser diodes. The difference between LEDs and laser diodes is that LEDs produce incoherent light, while laser diodes produce coherent light. For use in optical communications, semiconductor optical transmitters must be designed to be compact, efficient, and reliable, while operating in an optimal wavelength range, and directly modulated at high frequencies.
injects a series of optical pulses into the fiber under test. It also extracts, from the same end of the fiber, light that is scattered back and reflected back from points in the fiber where the index of refraction changes. (This is equivalent to the way that an electronic TDR measures reflections caused by changes in the impedance of the cable under test.) The intensity of the return pulses is measured and integrated as a function of time, and is plotted as a function of fiber length.
may be used for estimating the fiber’s length and overall attenuation, including splice and mated-connector losses. It may also be used to locate faults, such as breaks.
Plesiochronous Digital Hierarchy (PDH)
is a technology used in telecommunications networks to transport large quantities of data over digital transport equipment such as fiber optic and microwave radio systems.
Optical power meter
is a device used to measure the energy in an optical signal. A typical device consists of a display unit and a calibrated sensor. Power meters
are calibrated using a traceable calibration standard such as an NIST standard.
, including broadband and wireless router, is a device whose software and hardware are usually tailored to the tasks of routing and forwarding information. It is used to connect two or more logical subnets, which do not necessarily map one-to-one to the physical interfaces of the router.
Synchronous digital hierarchy (SDH) and synchronous optical network (SONET) based on circuit mode communication, meaning that each connection achieves a constant bit rate and delay refer to a group of fiber-optic transmission rates that can transport digital signals with different capacities.
Wavelength-division multiplexing (WDM)
is a technology which multiplexes multiple optical carrier signals on a single optical fiber by using different wavelengths of laser light to carry different signals. This allows for a multiplication in capacity, in addition to enabling bidirectional communications over one fiber.
A wireless LAN( WLAN) is a wireless local area network, which is the linking of two or more computers without using wires. WLAN utilizes spread-spectrum or OFDM modulation technology based on radio waves to enable communication between devices in a limited area, also known as the basic service set. This gives users the mobility to move around within a broad coverage area and still be connected to the network.
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An optical time-domain reflectometer (OTDR) is an optoelectronic instrument used to characterize an optical fiber. An OTDR injects a series of optical pulses into the … Read more
The erbium-doped fiber amplifier (EDFA)is the most deployed fiber amplifier as its amplification window coincides with the third transmission window of silica-based optical fiber. … Read more