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.
In order to terminate a Fiber Optic cable, the appropriate connector must be determined. The type of fiber-optic adapter that the terminated cable will connect to will dictate which connector will be used. The most common types that are added to fiber optic cable in inside plant environments are LC, SC, ST, and FC. Some fiber connectors are pre-polished mechanical connectors for ease of installation or anaerobic connectors which require cleaving and polishing. [1]
Once the appropriate connector has been identified, the termination process can begin. Common termination methods include no-epoxy-no-polish, epoxy and polish and pigtail splicing. [2] Regardless of the method, the beginning steps are the same. First, the sleeve, or secondary coating, must be stripped from the fiber. The primary coating must also be stripped away, revealing the bare fiber. Best practice guidelines from the FOA mandate that the bare fiber be cleaned by an alcohol wipe at this step. The face, or cross section must be cleaved first before the bare fiber is ready to be joined with a connector. Once the fiber is stripped, cleaned, and cleaved, it is ready to be joined to a connector.
A fiber pigtail is a single, short, usually tight-buffered, optical fiber that has an optical connector pre-installed on one end and a length of exposed fiber at the other end.
The end of the pigtail is stripped and fusion spliced to a single fiber of a multi-fiber trunk. Splicing of pigtails to each fiber in the trunk "breaks out" the multi-fiber cable into its component fibers for connection to the end equipment.
Pigtails can have female or male connectors. Female connectors could be mounted in a patch panel, often in pairs although single-fiber solutions exist, to allow them to be connected to endpoints or other fiber runs with patch fibers. Alternatively they can have male connectors and plug directly into an optical transceiver. [3]
A fanout kit is a set of empty jackets designed to protect fragile tight-buffered strands of fiber from a cable. This allows the individual fibers to be terminated without splicing, and without needing a protective enclosure such as a splicebox. This is normally an option with fiber distribution cable, or sometimes loose-buffer or ribbon cable, because these types of cable contain multiple strands that are designed for a permanent termination. The ribbon fanout pigtails include: Ribbon cable, Fanout kit, Fanout tubing and Connectors. [4]
Zip-cord style jackets, including those that contain Aramid yarn as the strength member, can be slipped over multiple fiber strands coming out of a loose buffer cable to convert it to a complete set of single-fiber cables that can be directly attached to optical connectors. A plastic boot is normally used for strain relief and protection from moisture. Use of a breakout kit enables a fiber-optic cable containing multiple loose buffer tubes to receive connectors without the splicing of pigtails. [5] [6]
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.
A cleave in an optical fiber is a deliberate, controlled break, intended to create a perfectly flat end face perpendicular to the fiber's longitudinal axis. The process of cleaving an optical fiber forms one of the steps in the preparation for a fiber splice operation, regardless of the subsequent splice being a fusion splice or a mechanical splice; the other steps in the preparation being those of stripping and fiber alignment. A good cleave is required for a successful low loss splice of an optical fiber, often it is the case that fibers spliced by identical methods tend to have different losses, this difference can often be attributed to the quality of their initial cleaves.
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.
Wire rope is composed of as few as two solid, metal wires twisted into a helix that forms a composite rope, in a pattern known as laid rope. Larger diameter wire rope consists of multiple strands of such laid rope in a pattern known as cable laid. Manufactured using an industrial machine known as a strander, the wires are fed through a series of barrels and spun into their final composite orientation.
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.
Fiber to the x or fiber in the loop is a generic term for any broadband network architecture using optical fiber to provide all or part of the local loop used for last mile telecommunications. As fiber optic cables are able to carry much more data than copper cables, especially over long distances, copper telephone networks built in the 20th century are being replaced by fiber.
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.
An optical ground wire is a type of cable that is used in overhead power lines. Such cable combines the functions of grounding and communications. An OPGW cable contains a tubular structure with one or more optical fibers in it, surrounded by layers of steel and aluminum wire. The OPGW cable is run between the tops of high-voltage electricity pylons. The conductive part of the cable serves to bond adjacent towers to earth ground, and shields the high-voltage conductors from lightning strikes. The optical fibers within the cable can be used for high-speed transmission of data, either for the electrical utility's own purposes of protection and control of the transmission line, for the utility's own voice and data communication, or may be leased or sold to third parties to serve as a high-speed fiber interconnection between cities.
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 optical communication in different applications, for example long-distance telecommunication or providing a high-speed data connection between different parts of a building.
Chiral Photonics, Inc., founded in 1999, is a photonics company based in Pine Brook, New Jersey, in the US.
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.
All-dielectric self-supporting (ADSS) cable is a type of optical fiber cable that is strong enough to support itself between structures without using conductive metal elements. It is used by electrical utility companies as a communications medium, installed along existing overhead transmission lines and often sharing the same support structures as the electrical conductors.
In telecommunications, a line splice is a method of connecting electrical cables or optical fibers.