Conrad L. Young’s Wired Broadband and Related Industry Glossary of Terms with Acronyms As of 15 February 2012 Open Access This document is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial
The material surrounding the cladding of a fiber. Generally a soft plastic material that protects the fiber from damage
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The material surrounding the cladding of a fiber. Generally a soft plastic material that protects the fiber from damage. (FiberOpticsInfo) 
Fiber Optic Cable Cross-Section courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/c Coaxial Cable Copper or copper-sheathed aluminum wire surrounded by an insulating layer of polyethylene foam, used by cable television systems. The insulating layer is covered with tubular shielding composed of tiny strands of braided copper wire, or a seamless aluminum sheath, and protective outer skin. The wire and the shielding react with each other to set up an electromagnetic field between them. This system reduces frequency loss and gives cable its great signal-carrying capacity. 
Coaxial Cable Cross-Section courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/c Coaxiality (Axial Misalignment) The axial (core centerline) alignment of fiber cores. Coaxiality insertion loss occurs when the positioning of the fiber cores is offset (misalignment). Coaxiality is also called radial offset or radial misalignment. The diagram below shows how the coaxiality (axial misalignment) of fiber cores result in insertion loss. This example shows that the some of the light from the fiber cores size will be absorbed by the cladding and not be transferred between the fibers. (Optical Dictionary) 
Coaxiality Misalignment Diagram courtesy of Optical Dictionary dot com, http://www.opticaldictionary.com/Optical_Dictionary_Connector_Loss_Definition.html Cocentricity The sharing of a common center point of circular items (such as a fiber core and fiber cladding or a center conductor in a coaxial cable). When a fiber core is not positioned in the center of the fiber (not concentric), this can cause losses as the end of one fiber may not exactly align with the core of the other fiber. To overcome some of the loss due to cocentricity offset, some optical connectors allow for the rotation of the connector to help align the fiber cores so their cocentric offsets are aligned as much as possible. The diagram below shows how cocentric offset can cause optical connector insertion loss. This diagram shows how the fiber core of one fiber has a concentric offset (core not in the center). When the end of one fiber is connected to the end of the other fiber, the fiber cores do not align. This results in some of the light signals from each fiber core not being transferred to the other fiber (blocked by the cladding). (Optical Dictionary) 
Cocentricity Diagram courtesy of Optical Dictionary dot com, http://www.opticaldictionary.com/Optical_Dictionary_Connector_Loss_Definition.html Co-Channel Interference One of the primary forms of man-made signal degradation associated with radio, co-channel interference occurs when the same carrier frequency reaches the same receiver from two separate transmitters as a result of spilling over from an adjoining cell. Code Division Multiple Access (CDMA) A spread spectrum access technology that assigns a code to each multiple access stream of data bits, transmits the spread data streams, and then, at the receiver, despreads and reassembles the data streams to their original format. CODEC Coder-DECoder Coder-Decoder (CODEC) A function or device that performs compression and decompression, typically on voice or video streams. Codes Exchange (CODEX) A telecommunications Codex specifies how different binary values sent across the telephone network are translated to and from specific sample voltages. See also Codec. CODEX Codes Exchange COFDM Coded Orthogonal Frequency Division Modulation; OFDM used in conjunction with channel coding techniques. As the overhead of doing this in an already digital system is low, and the gains substantial, practical OFDM/DMT systems are all actually COFDM. Although highly complex, COFDM has high performance under even very challenging channel conditions. By combining the OFDM technique with error-correcting codes, adaptive equalization and reconfigurable modulation, COFDM has the following properties:
COFDM also generally has a nearly 'white' spectrum, giving it benign electromagnetic interference properties with respect to other signals. Some COFDM systems use some of the sub carriers to carry pilot signals, which are used for frequency synchronizations, as frequency shifts during the transmission using the main modulation/demodulation process transform into bit errors in the decoded data. In wide area broadcasting, receivers can benefit from receiving signals from several spatially dispersed transmitters simultaneously, since transmitters will only destructively interfere with each other on a limited number of subcarriers, whereas in general they will actually reinforce coverage over a wide area. This is very beneficial in many countries, as it permits the operation of national single frequency networks, and avoids the replication of program content on different carrier frequencies which is necessary with FM or other forms of radio broadcasting. Also, because effectively the bit rate is slowed down on each sub-carrier, the effects of "ghosting" are much reduced. Such single frequency networks utilize the available spectrum more effectively than existing analog radio networks. (Word IQ) Coherent Communications In fiber optics, a communication system where the output of a local laser oscillator is mixed optically with a received signal and the difference frequency is detected and amplified. (FiberOpticsInfo) 
Coherent Communications Diagram courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/c Co-Location Ability of multiple satellites to share the same approximate geostationary orbital assignment frequently due to the fact that different frequency bands are used. (Satnews) Collision The result of two network nodes transmitting on the same channel at the same time. The transmitted data is not usable. Color Bar A test signal, typically containing six (6) basic colors: yellow, cyan, green, magenta, red, and blue, which is used to check the chrominance functions of color TV systems. (Channel Vision) Color Bar Test Signal The color bar test signal shown in the associated figure, consists of discrete steps of chroma and luminance levels that produce eight different colors superimposed upon standard synchronizing and blanking signals. [T1.Rpt16-1992] (ATIS) 
Color Bar Test Signal courtesy of ATIS Telecom Glossary 2007, http://www.atis.org/glossary/definition.aspx?id=6395 Color Burst In NTSC color, normally refers to a burst of approximately 9 cycles of 3.6MHz subcarrier on the back porch of the composite video signal. This serves as a color- synchronizing signal to establish a frequency and phase reference for the chrominance signal. Color Coordinate Transformation Computation of the tristimulus values of colors in terms of one set of primaries. Note: This computation may be performed electrically in a color television system. [IEEE] [After SMPTE] (ATIS) Color Decoder In color television technology, of a receiver, the circuitry that separates the chroma information from the video (gray-scale) information and processes the former into its constituent signal components. (ATIS)
Color Difference Signal The chrominance vectors carrying the color information in a composite format. Note: The color-difference signals have been defined by the ITU-R for existing television systems. (ATIS) Color Phase In color television technology, the instantaneous phase of the chroma signal with respect to that of the color burst signal. Note: The phase of the chroma signal at any given instant determines the color balance of the video signal at that instant. (ATIS) Color Subcarrier In NTSC color, the carrier whose modulation sidebands are added to the monochrome signal to convey color information, i.e., 3.6 MHz (3.579545 MHz). Color Temperature Of an electromagnetic source, especially in the optical regime, the hue or wavelength (spectral content) expressed or specified as the hypothetical wavelength(s) emitted by an ideal blackbody having an absolute temperature of n Kelvins (n K). Note 1: Higher numbers indicate hues in or toward the blue; lower numbers indicate hues in or toward the red. Note 2: Examples of color temperature are approximately 5000 K to 5500 K (daylight), approximately 4100 K (fluorescent lighting), and approximately 2800 K (incandescent). Note 3: Color temperature is commonly used to characterize ambient lighting or lighting employed for photographic purposes. [JSB/FAA] (ATIS) Colorimetry Measurement of colors based on a set of conventions. [After SMPTE] Also, the science of, or body of techniques employed in, (a) the measurement or characterization of color, and (b) the interpretation of the results. Note: Human perception of color is a subjective phenomenon resulting from and dependent upon the properties of the eye and the brain. (ATIS) Combiner A signal combining network that allows several discrete inputs to be added into a common bandwidth and that has high isolation between inputs. Also may refer to a power combining network. Combining Network A passive network that permits the addition of several signals into one combined output with a high degree of isolation between individual inputs. It may be a power or frequency combiner. Common Carrier Any point-to-point communications relay service available to the general public at non-discriminatory rates. The carrier cannot control message content (e.g., telephone companies). Common Path Distortion (CPD) The interference of return path signaling caused by the forward path. Common-path Interferometers Some interferometers use a common beam path but different polarizations for the two beams. This has the advantage that fluctuations of the geometric path length do not affect the interferometer output, whereas the interferometer can be a sensitive detector for birefringence. (Encylopedia of Laser Physics and Technology) Communication Satellite An electronic retransmission vehicle located in space in a fixed earth orbit. Signals are transmitted to the satellite from earth station antenna, amplified and sent back to earth for reception by other earth station antennas. Communication Server A dedicated standalone system that manages communications activities for other computers. Companding A noise-reduction technique that applies single compression at the transmitter and complementary expansion at the receiver. (Satnews) Competitive Local Exchange Carrier (CLEC) An alternative local telephone company that competes against incumbent Local Exchange Carriers (LECs) for local and access business. Also known as a Competitive Access Provider (CAP) or Alternate Local Telephone (ALT) company. Companies that build high-bandwidth fiber-optic networks to compete with the incumbent telephone and cable operators. See also Overbuilder. Complementary Colors 1. With respect to additive mixing, any pair of colors that are radially opposite one another relative to the white point on a chromaticity chart, e.g., the familiar CIE chart. Note: Complementary colors may be combined additively to produce the perception of white. 2. Analogous pairs of colors with respect to subtractive mixing. (ATIS) Composite Baseband The unclamped and unfiltered output of the satellite receiver's demodulator circuit, containing the video information as well as all transmitted subcarriers. (Satnews) Composite Baseband Signal The complete audio and video signal without a carrier wave. NTSC video baseband is from zero to 4.2 MHz. (Arris Glossary of Terms) Composite Second Order Beat (CSO) The peak of the average level of distortion products due to second-order non- linearities in cable system equipment. Composite Sync A signal consisting of horizontal sync pulses, vertical sync pulses, and equalizing pulses only, with a no-signal reference level. (FiberOpticsInfo) Composite Triple Beat (CTB) The peak of the average level of distortion components due to third-order non- linearities in cable system equipment. Composite Video Signal The complete video signal. For monochrome, it consists of the picture signal and the blanking and synchronizing signals. For color, additional color synchronizing signals and color picture information are added. Compression A method for compacting the digital representation of a signal for more efficient transmission or storage. Compression Algorithms Software that allows codecs to reduce the number of bits required for data storage or transmission. (Satnews) Compression Ratio The measurement of compressed data. For example, a file compressed into 1/4th of its original size can be expressed as 4:1, 25%, 75% or 2 bits per byte. (Encyclopedia) Compulsory License Legislation requiring copyright holders to license users of copyrighted material (cable television operators) on a uniform basis and for a stipulated fee. COMSAT The Communications Satellite Corporation (part of Lockheed Martin) which serves as the U.S. Signatory to INTELSAT and INMARSAT. (Satnews) Concatenation The process of connecting pieces of fiber together. (FiberOpticsInfo) Concentrator 1) A functional unit that permits a common path to handle more data sources than channels currently available within the path. Usually provides communication capability between many low-speed, asynchronous channels and one or more high-speed, synchronous channels. 2) A device that connects a number of circuits, which are not all used at once, to a smaller group of circuits for economy. (FiberOpticsInfo) Concentricity In fiber optic cable, the measurement of how well-centered the core is within the cladding. (FiberOpticsInfo) 
Concentricity Diagram courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/c Conditional Access (CA) and Encryption A system that provides selective access to programming to individual customers in exchange for payment. Conductor A material suitable for carrying an electric current. (Arris Glossary of Terms) Conduit A pipe or tube, of tile, asbestos-cement, plastic or steel, which is placed underground to form ducts through which cable can be passed. (Arris Glossary of Terms) Confidentiality A way to ensure that information is not disclosed to anyone other than the intended parties. Information is encrypted to provide confidentiality. Also known as privacy. Connectionless Network This is a type of packet-switched network in which no logical connection is required between sending and receiving stations. Each data unit or packet includes the source and destination addresses and can take any available route between source and destination. The Internet Protocol (IP) is connectionless. Connector Any device for making a temporary or semi-permanent connection. (Arris Glossary of Terms) Connector Variation The maximum value in dB of the difference in insertion loss between mating optical connectors (e.g., with remating, temperature cycling, etc.). Also called optical connector variation. (FiberOpticsInfo) Constant Bit Rate (CBR) A service class intended for real-time applications, or those requiring tightly constrained delay and delay variation, as would be appropriate for voice and video applications. The constant availability of a fixed quantity of bandwidth is considered appropriate for CBR service. Constructive Interference Any interference that increases amplitude of the resultant signal. For example, when the wave forms are in phase, they can create a resultant wave equal to the sum of multiple light waves. (FiberOpticsInfo) 
Constructive Interference Illustration courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/c Contamination Loss The optical signal loss that occurs due to the inability of optical signals to pass through contamination particles (e.g. dirt) in an optical connector. A key potential source of contamination for the fiber connection is oil that is transferred from fingers to the surface of the connector. The diagram below shows how dirt particles (contamination) in an optical connector can cause insertion loss. This diagram shows that some of the signals are absorbed or reflected by the contamination particles as the optical signal attempts to pass from one fiber to the other fiber. (Optical Dictionary) 
Contamination Diagram courtesy of Optical Dictionary dot com, http://www.opticaldictionary.com/Optical_Dictionary_Connector_Loss_Definition.html Content Typically used to refer to audio, video and graphic materials used by an application. Sometimes data and applications are also grouped into this term. Content Protection/Copy Protection (CP) Content protection is a mechanism to protect the unauthorized copying of video and audio programming. Contrast The range of light and dark values in a picture, or the ratio between the maximum and minimum brightness values. A high-contrast picture would contain intense blacks and whites; a lower-contrast picture would contain only shades of gray. Conus Contiguous United States. In short, all the states in the U.S. except Hawaii and Alaska. (Satnews) Converter Device that is attached between the television set and the cable system that can increase the number of channels available on the TV, enabling it to accommodate the multiplicity of channels offered by cable TV. Converter, Subscriber’s A unit or device that changes the frequency of carriers to a carrier (or carriers) that can be tuned, detected, and displayed by conventional television receivers at the subscriber’s premises. (Arris Glossary of Terms) Cookies A special text file that a Web site stores on your hard drive used to identify you to the Web site the next time you visit. A cookie records your preferences when using a particular site, and can also save the information filled out in online forms. They are used to send browser-specific pages, or pages based on information you have provided to the Web site. Cooled DFB Laser Distributed Feedback laser; employs thermoelectric cooler (TEC) to improve laser performance and reliability. Because of its stable wavelength and narrow optical bandwidth, cooled DFB Lasers are commonly used in narrow wavelength DWDM optical communication systems. (Althos) Coordinated Universal Time (UTC) A reference time standard established by the CCIR (a predecessor of the ITU) and maintained by the Bureau International des Poids et Mesures (BIPM). Formerly Greenwich Mean Time (GMT). Copy Control Information (CCI) This information is stored on a CableCARD device and delivered to the host to control the copying of content. It is delivered to the CableCARD from the headend, based on arrangements made between the network operator and the content provider. CORBA Common Object Request Broker Architecture Core The light-conducting central portion of an optical fiber composed of material with a higher index of refraction than the cladding. The portion of the fiber that transmits light. (FiberOpticsInfo)
Fiber Optic Cable Cross-Section courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/c Core Diameter The diameter of the circle that circumscribes the core area. (Arris Glossary of Terms) Core Size Mismatch The signal insertion loss that occurs in a fiber optic connector due to the difference between the size of the fiber core in one connector compared to the size of the fiber core in the mating connector. The diagram below shows how the core size of fiber strands can vary. This example shows that the light from the larger core size will not be transferred to the fiber with the smaller core size. (Optical Dictionary) 
Core Size Mismatch Diagram courtesy of Optical Dictionary dot com, http://www.opticaldictionary.com/Optical_Dictionary_Connector_Loss_Definition.html Download 2.22 Mb. Share with your friends:
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