The optical power budget in a fiber-optic communication link is the allocation of available optical power among various loss-producing mechanisms such as launch coupling loss, fiber attenuation, splice losses, and connector losses, in order to ensure that adequate signal strength is available at the receiver. In optical power budget attenuation is specified in decibel (dB) and optical power in dBm.
In fiber-optic communication, a single-mode optical fiber (SMF), also known as fundamental- or mono-mode, is an optical fiber designed to carry only a single mode of light - the transverse mode. Modes are the possible solutions of the Helmholtz equation for waves, which is obtained by combining Maxwell's equations and the boundary conditions. These modes define the way the wave travels through space, i.e. how the wave is distributed in space. Waves can have the same mode but have different frequencies. This is the case in single-mode fibers, where we can have waves with different frequencies, but of the same mode, which means that they are distributed in space in the same way, and that gives us a single ray of light. Although the ray travels parallel to the length of the fiber, it is often called transverse mode since its electromagnetic oscillations occur perpendicular (transverse) to the length of the fiber. The 2009 Nobel Prize in Physics was awarded to Charles K. Kao for his theoretical work on the single-mode optical fiber. The standards G.652 and G.657 define the most widely used forms of single-mode optical fiber.
A transmission medium is a system or substance that can mediate the propagation of signals for the purposes of telecommunication. Signals are typically imposed on a wave of some kind suitable for the chosen medium. For example, data can modulate sound, and a transmission medium for sounds may be air, but solids and liquids may also act as the transmission medium. Vacuum or air constitutes a good transmission medium for electromagnetic waves such as light and radio waves. While a material substance is not required for electromagnetic waves to propagate, such waves are usually affected by the transmission media they pass through, for instance, by absorption or reflection or refraction at the interfaces between media. Technical devices can therefore be employed to transmit or guide waves. Thus, an optical fiber or a copper cable is used as transmission media.
A mechanical splice is a junction of two or more optical fibers that are aligned and held in place by a self-contained assembly. The fibers are not permanently joined, just precisely held together so that light can pass from one to another. This impermanence is an important advantage over fusion splicing, as splice loss, the amount of power that the splice fails to transmit, can be better measured and prevented.
An optical fiber connector is a device used to link optical fibers, facilitating the efficient transmission of light signals. An optical fiber connector enables quicker connection and disconnection than splicing.
A patch cable, patch cord or patch lead is an electrical or fiber-optic cable used to connect one electronic or optical device to another for signal routing. Devices of different types are connected with patch cords.
Breakout-style fiberoptic cable, is an optical fiber cable containing several jacketed simplex optical fibers packaged together inside an outer jacket. This differs from distribution-style cable, in which tight-buffered fibers are bundled together, with only the outer cable jacket of the cable protecting them. The design of breakout-style cable adds strength for ruggedized drops, however the cable is larger and more expensive than distribution-style cable. Breakout cable is suitable for short riser and plenum applications and also for use in conduits, where a very simple cable run is planned to avoid the use of any splicebox or spliced fiber pigtails.
An optical fiber, or optical fibre, is a flexible glass or plastic fiber that can transmit light from one end to the other. Such fibers find wide usage in fiber-optic communications, where they permit transmission over longer distances and at higher bandwidths than electrical cables. Fibers are used instead of metal wires because signals travel along them with less loss and are immune to electromagnetic interference. Fibers are also used for illumination and imaging, and are often wrapped in bundles so they may be used to carry light into, or images out of confined spaces, as in the case of a fiberscope. Specially designed fibers are also used for a variety of other applications, such as fiber optic sensors and fiber lasers.
Microducts are small ducts used for the installation of fibre optic cables. They have a typical size ranging from 3 to 16 mm and are installed as bundles within larger ducts.
Fiber-optic communication is a method of transmitting information from one place to another by sending pulses of infrared or visible light through an optical fiber. The light is a form of carrier wave that is modulated to carry information. Fiber is preferred over electrical cabling when high bandwidth, long distance, or immunity to electromagnetic interference is required. This type of communication can transmit voice, video, and telemetry through local area networks or across long distances.
A fiber-optic cable, also known as an optical-fiber cable, is an assembly similar to an electrical cable but containing one or more optical fibers that are used to carry light. The optical fiber elements are typically individually coated with plastic layers and contained in a protective tube suitable for the environment where the cable is used. Different types of cable are used for fiber-optic communication in different applications, for example long-distance telecommunication or providing a high-speed data connection between different parts of a building.
Fiber Optic cable termination is the addition of connectors to each optical fiber in a cable. The fibers need to have connectors fitted before they can attach to other equipment. Two common solutions for fiber cable termination are pigtails and fanout kits or breakout kits.
A fiber management system (FMS) manages optical fiber connections from outside of fiber rack to the fiber routers. Fiber-optic cable duct containing many fibers comes from far end sites and terminates on the FMS using splicing technology. FMS has fiber in and fiber out ports. From fiber out port the fiber patch will go to fiber optics based router.
Nyfors Teknologi AB is a high-end supplier of advanced optical fiber handling equipment, based in Stockholm, Sweden. The company develops and manufactures equipment used in optical fiber fusion splicing, including products for stripping and preparation, testing and analysing and fiber end-face inspection, but is most well known for its automated optical fiber recoating and fiber cleaving systems. Nyfors products are sold internationally to customers within a wide range of industrial sectors and to public and private research institutions.
Recoating is the process of restoring the primary coating to stripped optical fiber sections after fusion splicing. In the recoating process, the spliced fiber is restored to its original shape and strength, using a recoater. The stripped fiber section is recoated by filling a recoating resin, usually acrylate into transparent moulds. The resin is then cured with UV light. It is often desirable to perform a proof-test after recoating, to ensure that the splice is strong enough to survive handling, packaging and extended use.
Stripping is the act of removing the protective polymer coating around optical fiber in preparation for fusion splicing. The splicing process begins by preparing both fiber ends for fusion, which requires that all protective coating is removed or stripped from the ends of each fiber. Fiber optical stripping can be done using a special stripping and preparation unit that uses hot sulfuric acid or a controlled flow of hot air to remove the coating. There are also mechanical tools used for stripping fiber which are similar to copper wire strippers. Fiber optical stripping and preparation equipment used in fusion splicing is commercially available through a small number of specialized companies, which usually also design machines used for fiber optical recoating.
Rayleigh scattering-based distributed acoustic sensing (DAS) systems use fiber optic cables to provide distributed strain sensing. In DAS, the optical fiber cable becomes the sensing element and measurements are made, and in part processed, using an attached optoelectronic device. Such a system allows acoustic frequency strain signals to be detected over large distances and in harsh environments.
A fiber-optic adapter connects two optical fiber connectors in the fiber optic lines.
The Fiber Optic Association (FOA) is an international professional society of fiber optics. The FOA was founded in 1995 by a group of trainers from industry, government and education who wanted to create industry standards for training and certifying fiber optic technicians. The FOA is a not-for-profit 501(c)6 organization based in California, USA, that has over 200 affiliated training organizations in over 40 countries. FOA approves fiber optic training organizations and certifies their instructors who train designers, installers and operators of all types of fiber optic networks. FOA programs are used by many organizations, companies and trade unions to train and certify their workers.
In telecommunications, a line splice is a method of connecting electrical cables or optical fibers.
