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Multi-mode Fibre
Multi-mode optical fiber is a type of optical fiber mostly used for communication over short distances, such as within a building or on a campus. Multi-mode links can be used for data rates up to 800 Gbit/s. Multi-mode fiber has a fairly large core diameter that enables multiple light modes to be propagated and limits the maximum length of a transmission link because of modal dispersion. The standard G.651.1 defines the most widely used forms of multi-mode optical fiber. Applications The equipment used for communications over multi-mode optical fiber is less expensive than that for single-mode optical fiber. Typical transmission speed and distance limits are 100 Mbit/s for distances up to 2 km ( 100BASE-FX), 1 Gbit/s up to 1000 m, and 10 Gbit/s up to 550 m. Because of its high capacity and reliability, multi-mode optical fiber generally is used for backbone applications in buildings. An increasing number of users are taking the benefits of f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromatic Dispersion
Dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency. Sometimes the term chromatic dispersion is used to refer to optics specifically, as opposed to wave propagation in general. A medium having this common property may be termed a dispersive medium. Although the term is used in the field of optics to describe light and other electromagnetic waves, dispersion in the same sense can apply to any sort of wave motion such as acoustic dispersion in the case of sound and seismic waves, and in gravity waves (ocean waves). Within optics, dispersion is a property of telecommunication signals along transmission lines (such as microwaves in coaxial cable) or the pulses of light in optical fiber. In optics, one important and familiar consequence of dispersion is the change in the angle of refraction of different colors of light, as seen in the spectrum produced by a dispersive prism and in chromatic aberration of lenses. Design of compound achr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gigabit Ethernet
In computer networking, Gigabit Ethernet (GbE or 1 GigE) is the term applied to transmitting Ethernet frames at a rate of a gigabit per second. The most popular variant, 1000BASE-T, is defined by the IEEE 802.3ab standard. It came into use in 1999, and has replaced Fast Ethernet in wired local networks due to its considerable speed improvement over Fast Ethernet, as well as its use of cables and equipment that are widely available, economical, and similar to previous standards. The first standard for faster 10 Gigabit Ethernet was approved in 2002. History Ethernet was the result of research conducted at Xerox PARC in the early 1970s, and later evolved into a widely implemented Physical layer, physical and Data link layer, link layer protocol. Fast Ethernet increased the speed from 10 to 100 megabits per second (). Gigabit Ethernet was the next iteration, increasing the speed to . The initial standard for Gigabit Ethernet was produced by the IEEE in June 1998 as IEEE 802.3z ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethernet
Ethernet ( ) is a family of wired computer networking technologies commonly used in local area networks (LAN), metropolitan area networks (MAN) and wide area networks (WAN). It was commercially introduced in 1980 and first standardized in 1983 as IEEE 802.3. Ethernet has since been refined to support higher bit rates, a greater number of nodes, and longer link distances, but retains much backward compatibility. Over time, Ethernet has largely replaced competing wired LAN technologies such as Token Ring, FDDI and ARCNET. The original 10BASE5 Ethernet uses a thick coaxial cable as a shared medium. This was largely superseded by 10BASE2, which used a thinner and more flexible cable that was both less expensive and easier to use. More modern Ethernet variants use Ethernet over twisted pair, twisted pair and fiber optic links in conjunction with Network switch, switches. Over the course of its history, Ethernet data transfer rates have been increased from the original to the lates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunications Industry Association
The Telecommunications Industry Association (TIA) is accredited by the American National Standards Institute (ANSI) to develop voluntary, consensus-based industry standards for a wide variety of information and communication technology (Information and communication technologies, ICT) products, and currently represents nearly 400 companies. TIA's Standards and Technology Department operates twelve engineering committees, which develop guidelines for private radio equipment, cellular towers, data terminals, satellites, telephone terminal equipment, accessibility, VoIP devices, structured cabling, data centers, mobile device communications, multimedia multicast, vehicular telematics, healthcare ICT, Machine to machine, machine to machine communications, and smart grid, smart utility networks. Active participants include communications equipment manufacturers, service providers, government agencies, academic institutions, and end-users are engaged in TIA's standards setting proces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modal Bandwidth
Modal may refer to: * Modal (textile) * Modal (drug) * Modal (company) See also * Mode (other) Mode ( meaning "manner, tune, measure, due measure, rhythm, melody") may refer to: Arts and entertainment * MO''D''E (magazine), a defunct U.S. women's fashion magazine * ''Mode'' magazine, a fictional fashion magazine which is the setting fo ... * Modality (other) * {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ISO 11801
International standard ISO/IEC 11801 ''Information technology — Generic cabling for customer premises'' specifies general-purpose telecommunication cabling systems (structured cabling) that are suitable for a wide range of applications (analog and ISDN telephony, various data communication standards, building control systems, factory automation). It is published by ISO/IEC JTC 1/ SC 25/WG 3 of the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). It covers both balanced copper cabling and optical fibre cabling. The standard was designed for use within commercial premises that may consist of either a single building or of multiple buildings on a campus. It was optimized for premises that span up to 3 km, up to 1 km2 office space, with between 50 and 50,000 persons, but can also be applied for installations outside this range. A major revision was released in November 2017, unifying requirements for commercial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graded-index Fiber
A graded-index fiber, or gradient-index fiber, is an optical fiber whose core has a refractive index that decreases ''continuously'' with increasing radial distance from the optical axis of the fiber, as opposed to a step-index fiber, which has a uniform index of refraction in the core, and a lower index in the surrounding cladding. Because parts of the core closer to the fiber axis have a higher refractive index than the parts near the cladding, light rays follow sinusoidal paths down the fiber. The most common refractive index profile for a graded-index fiber is very nearly parabolic. The parabolic profile results in continual refocusing of the rays in the core, and minimizes modal dispersion. Multi-mode optical fiber can be built with either a graded-index or a step-index profile. The advantage of graded-index multi-mode fiber compared to step-index fiber is a considerable decrease in modal dispersion. This means that the trip time of photons traversing the fiber is mor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Step-index Profile
For an optical fiber, a step-index profile is a refractive index profile characterized by a uniform refractive index within the core and a sharp decrease in refractive index at the core- cladding interface so that the cladding is of a lower refractive index. The step-index profile corresponds to a power-law index profile with the profile parameter approaching infinity. The step-index profile is used in most single-mode fibers and some multimode fibers. A step-index fiber is characterized by the core and cladding refractive indices ''n1'' and ''n2'' and the core and cladding radii a and b. Examples of standard core and cladding diameters 2a/2b are 8/125, 50/125, 62.5/125, 85/125, or 100/140 (units of μm). The fractional refractive-index change \triangle \, = \frac \ll \ 1. The value of n1 is typically between 1.44 and 1.46, and \triangle is typically between 0.001 and 0.02. Step-index optical fiber is generally made by doping high-purity fused silica glass (SiO2) with di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladding (fiber Optics)
Cladding in optical fibers is one or more layers of materials of lower refractive index in intimate contact with a core material of higher refractive index. The cladding causes light to be confined to the core of the fiber by total internal reflection at the boundary between the core and cladding. Light propagation within the cladding is typically suppressed for most fibers. However, some fibers can support ''cladding modes'' in which light propagates through the cladding as well as the core. Depending upon the quantity of modes that are supported, they are referred to as multi-mode fibers and single-mode fibers. Improving transmission through fibers by applying a cladding was discovered in 1953 by Dutch scientist Bram van Heel. History The fact that transmission through fibers could be improved by applying a cladding was discovered in 1953 by van Heel, who used it to demonstrate image transmission through a bundle of optical fibers. Early cladding materials included o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Fiber Optic Association
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 Nonprofit organization, not-for-profit 501(c) organization#501(c)(6), 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. History At the 1994 Fiber U Conference in Boston, the fiber optic instructors decided that it was time to create a professional society for fiber optics. The fiber optic instructors represented a number of fiber optic manufacturers includi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
