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
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Electronic DriverIt is important to use an electronic driver which is both well matched to the EOM and suitable for the particular application. For example, different kinds of EOMs require different drive voltages, and the driver should also be designed for the given electrical capacitance of the EOM. Some drivers are suitable for a purely sinusoidal modulation, whereas broadband devices work in a large range of modulation frequencies. Many problems can be avoided by purchasing an electro-optic modulator together with the electronic driver from the same supplier, because the responsibility for the overall performance is then at one place. ApplicationsSome typical applications of electro-optic modulators are:
EPG Electronic Program Guide Episode An episode is a single installment of a dramatic work such as a serial television or radio program. An episode is a part of a sequence of a body of work, akin to a chapter of a book. (Fain) EPoC Ethernet Passive Optical Network (EPON) Provisioning over Coaxial, a proposed physical layer (PHY) networking standard for operating the EPON protocol over coaxial distribution networks, such as cable industry hybrid fiber coax (HFC). EPoC is envisioned to support symmetric duplex deployments up to 10 Gbps data delivery rate with no substantive changes to other EPON sublayers. Additional operations, administration, and maintenance (OAM) messages for configuration and monitoring are anticipated as part of the EPoC standard. (Laubach) EQAM EdgeQAM Modulator; a head end or hub device that receives packets of digital video or data. It re-packetizes the video or data into an MPEG transport stream and digitally modulates the digital transport stream onto a downstream RF carrier using quadrature amplitude modulation (QAM). (CableLabs) Equal Access The offering of access to local exchange facilities on a non-discriminatory basis. Equilibrium Mode Distribution The steady modal state of a multimode fiber in which the relative power distribution among modes is independent of fiber length. (FiberOpticsInfo) Equalization A means of modifying the frequency and/or phase response of an amplifier or network, thereby resulting in a flat overall response. Or, the spacing and operation of amplifiers, so that the gain provided by the amplifier, per transmission frequency, coincides with the signal loss at the same frequency within communications devices. Equalization is achieved by circuitry that compensates for the differences in attenuation at different frequencies. (Arris Glossary of Terms) Equalized Loss Any loss in cable television systems caused by coaxial cable; also, insertion loss of components designed to match cable loss characteristics. Equalizer, Cable (EQ) A network device designed to compensate for the frequency/ loss characteristics of a cable, so as to permit the system to pass all frequencies in a uniform manner. (Arris Glossary of Terms) Equalizing Pulses Pulses of one half the width of the horizontal sync pulses which are transmitted at twice the rate of the horizontal sync pulses during the blanking intervals immediately preceding and following the vertical sync pulses. The action of these pulses causes the vertical deflection to start at the same time in each interval, and also serves to keep the horizontal sweep circuits in step during the vertical blanking intervals immediately preceding and following the vertical sync pulse. Equatorial Orbit An orbit with a plane parallel to the earth's equator. (Satnews) ER Extinction Ratio; applies to optical intensity laser modulators. ER characterizes the efficiency of the modulator to transmit light when in an “ON” state and block light in an “OFF” state. Two different extinction ratios are defined: DC extinction ratio and RF dynamic extinction ratio (DER). (Hauden) ERDC DC Extinction Ratio; measured with no electrical signal applied on the RF input port of an intensity modulator. The bias voltage on the DC port (connected to the DC electrode) is adjusted to achieve an “ON” state (Pout is maximum) then an “OFF” state (Pout is minimum). ERDC is measured as the ratio of Poutmax over Poutmin and is expressed in dB. (Hauden) Error Correction In digital transmission systems, a scheme that adds overhead to the data to permit a certain level of errors to be detected and corrected. (FiberOpticsInfo) Error Detection Checking for errors in data transmission. A calculation based on the data being sent; the results of the calculation are sent along with the data. The receiver then performs the same calculation and compares its results with those sent. If the receiver detects an error, it can be corrected, or it can simply be reported. (FiberOpticsInfo) Error Rate A measure of the performance of a digital transmission system. It can be specified as a bit error rate (the probability of error per bit transmitted), as a block error rate (the probability of one or more errors in a specified-length block of bits), or in other forms such as percent error-free seconds. Errored Second Any 1-sec interval containing at least one bit error. ES Elementary Stream ESC Engineering Service Circuit; the 300-3,400 Hertz voice plus teletype (S+DX) channel used for earth station-to-earth station and earth station-to-operations center communications for the purpose of system maintenance, coordination and general system information dissemination. In analog (FDM/FM) systems there are two S+DX channels available for this purpose in the 4,000-12,000 Hertz portion of the baseband. In digital systems there are one or two channels available which are usually convened to a 32 or 64 Kbps digital signal and combined with the earth station traffic digital bit stream. Modern ESC equipment interfaces with any mix of analog and digital satellite carriers, as well as backhaul terrestrial links to the local switching center. (Satnews) ESCON Enterprise Systems Connection; a duplex optical connector used for computer-to-computer data exchange. (FiberOpticsInfo) ESD Electrostatic Discharge. Static discharge which may damage electronic equipment. (Arris Glossary of Terms) E-SMG Embedded Subscriber Media Gateway Ethernet
Ethernet Diagram courtesy of fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/e ETS European Telecommunications Standard. Prefix for certain ETSI documents. ETSI European Telecommunications Standards Institute eTV
ETV Educational Television Station EuroDOCSIS As frequency allocation band plans differ between U.S. and European CATV systems, DOCSIS standards have been modified for use in Europe. These changes were published under the name of "EuroDOCSIS". The main differences account for differing TV channel bandwidths; European cable channels conform to PAL TV standards and are 8 MHz wide, whereas in North America channels conform to ATSC standards which specify 6 MHz. The wider bandwidth in EuroDOCSIS architectures permits more bandwidth to be allocated to the downstream data path (toward the user). EuroDOCSIS certification testing is executed by Excentis (formerly known as tComLabs), while DOCSIS® certification testing is executed by CableLabs. Typically, customer premises equipment (CPE) receives "certification", while CMTS equipment receives "qualification". Most cable systems in Japan and Colombia utilize the North American version of DOCSIS®, while some employ a variant of DOCSIS® that uses upstream channels that are based on a 9.216 MHz master clock (as opposed to 10.24 MHz used in DOCSIS®/EuroDOCSIS) resulting in upstream channel widths that are a power-of-two division of 6 MHz (as opposed to 6.4 MHz in DOCSIS®/EuroDOCSIS). The ITU Telecommunication Standardization Sector (ITU-T) has approved the various versions of DOCSIS® as international standards. While ITU-T Recommendation J.112 Annex B corresponds to DOCSIS®/EuroDOCSIS 1.1, Annex A describes an earlier European cable modem system ("DVB EuroModem") based on ATM transmission standards. Annex C describes a variant of DOCSIS® 1.1 that is designed to operate in Japanese cable systems. The ITU-T Recommendation J.122 main body corresponds to DOCSIS® 2.0, J.122 Annex F corresponds to EuroDOCSIS 2.0, and J.122 Annex J describes the Japanese variant of DOCSIS® 2.0 (analogous to Annex C of J.112). European Norms (EN) Prefix for certain European Telecommunications Standards Institute (ETSI) documents. European Telecommunications Standards Institute (ETSI) The European equivalent of ANSI (American National Standards Institute). Eutelsat The European Telecommunications Satellite Organization which is headquartered in Paris, France. It provides a satellite network for Europe and parts of North Africa and the Middle East. (Satnews) Evanescent Wave Light guided in the inner part of an optical fiber’s cladding rather than in the core, i.e. the portion of the light wave in the core that penetrates into the cladding. (FiberOpticsInfo) 
Evanescent Wave Diagram courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/e Event Message A message capturing a single portion of a connection. Events Asynchronous communication between applications and the OpenCable system on which they are being executed. They provide communication between solution elements. An event may also refer to a unit of programming, such as a movie, an episode of a television show, a newscast or a sports game. EVM Error Vector Magnitude; a measurement of demodulator performance in the presence of impairments. The measured symbol location obtained after decimating the recovered waveform at the demodulator output is compared against the ideal symbol locations. The root-mean-square (RMS) EVM and phase error are then used in determining the EVM measurement over a window of N demodulated symbols. As shown below, the measured symbol location by the demodulator is given by w. However, the ideal symbol location (using the symbol map) is given by v. Therefore, the resulting error vector is the difference between the actual measured and ideal symbol vectors, i.e., e=w–v. (Zone NI ) The error vector e for a received symbol is graphically represented as follows: 
Graphical Representation of Error Vector In Figure above, v is the ideal symbol vector, w is the measured symbol vector, w–v is the magnitude error, θ is the phase error, e=w–v) is the error vector, and e/v is the EVM. E-VSB Enhanced Vestigial Side Band; E-VSB is an optional enhancement to the ATSC standards that employ 8-VSB modulation for the transmission and reception of digital signals, including digital television (DTV) and high definition television (HDTV). E-VSB is a method to add increased error protection to a portion of the originally released “normal” ATSC 8-VSB transmission. E-VSB is intended to improve reception where signals are weaker, including fringe reception areas, and on portable devices such as handheld televisions or mobile phones. It does not cause problems to older “normal” 8-VSB capable receivers, but they cannot take advantage of E-VSB features. E-VSB was approved by the ATSC committee in 2004. However, E-VSB has been implemented by few stations or manufacturers as of the writing of this document. For mobile applications, ATSC with “normal” 8-VSB suffers significant signal degradation caused by the Doppler Effect. Additionally, low-power handheld receivers are usually equipped with smaller antennas. These devices with smaller antennas have a relatively poor signal-to-noise ratio, which can be detrimental and disruptive to digital signals. The E-VSB standard provides for Reed-Solomon forward error correction to alleviate the data corruption caused by these issues. Additionally, the standard can use either the MPEG-4 AVC or VC-1 video codecs. As these codecs have higher video compression than the original MPEG-2, they require less bandwidth. Though 8VSB lacks both link adaptation and hierarchical modulation of the DVB standard, which would allow the SDTV part of an HDTV signal (or the LDTV part of SDTV) to be received even in fringe reception areas where signal strength is low; E-VSB yields a similar benefit. However, E-VSB places a significant processing overhead on the receiver, as well as a significant transmission overhead on the broadcaster's total bitrate. These are not a problem with DVB-H. The Figure below shows a simple block diagram of the processing in the E-VSB system. Some of the transmitted 8-VSB symbols (a selectable number of data segments in each 8-VSB data frame) are dedicated to carrying the desired enhanced data and associated E-VSB forward-error-correction bits. Data to be transmitted via the enhanced process is first subject to the addition of forward error correction. It is then formatted into standard MPEG transport packets. The packets of enhanced data are then interspersed with packets intended for normal 8-VSB transmission, according to a pre-determined algorithm. All the packets are then processed by the normal 8-VSB forward error correction, so that no errors are produced in legacy 8-VSB receivers due to the E-VSB process. (Whitaker) 
Figure. E-VSB modulation system overview (courtesy of “ATSC Recommended Practice: E-VSB Implementation Guidelines”, Document A/112, dtd 18 April 2006 Excess Loss Excess loss is the ratio of the optical power launched at the input port of the coupler to the total optical power measured from all output ports, expressed in dB. (AOFR) Exclusivity The provision in a commercial television film contract that grants exclusive playback rights for the film or episode to a broadcast station in the market it serves. Under the FCC's rules cable operators cannot carry distant signals which violate local television stations' exclusivity agreements. Execution Engine (EE) The portion of the OpenCable Platform which will provide a full programming environment for performing complex logic and arithmetic operations which the Presentation Engine (PE) cannot handle alone. In the EE, which will include Sun's JavaTV programming environment, ITV developers will write interactive applications, in Java, following the OCAP specification. When a cable customer with an OpenCable-compliant set-top box accesses the application through the user interface, the application is transparently downloaded into the box. A Java engine or JAVA Virtual Machine (JVM) resident in the set-top decodes the application downloaded over the network, and runs it. Or the execution engine is a platform- independent interface that permits programmatic content as part of the OpenCable Application Platform. Extended Subsplit A frequency division scheme that allows bi-directional traffic on a single coaxial cable. Reverse path signals come to the headend from 5 to 42 MHz. Forward path signals go from the headend from 50 or 54 MHz to the upper frequency limit. Extensible Hypertext Mark-up Language (XHTML) A reformulation of HTML in XML. XHTML is a family of current and future document types and modules that reproduce, subset, and extend HTML 4. XHTML family document types are XML based, and ultimately are designed to work in conjunction with XML-based user agents. Extension Adapter This adapter is used when sufficient cable is not available for installation. It has a pin which seizes and retains the cable center conductor. The pin then extends through the body and is retained within the equipment housing. (Arris Glossary of Terms)
F: F-59, F-6 (F-56), F-7, F-11 A male connector that seizes the outer braid and jacket of an RG-59, RG-6 (RG-56), RG-7 or RG-11 drop cable. The center conductor of the cable extends through this connector, becoming the center contact. (Arris Glossary of Terms) F-61 Equipment or panel mounted connector with solder lug, threaded 3/8-32. (Arris Glossary of Terms) F-71 A double-ended "F" connector, used when sufficient cable is not available for installation. Male/male splice. (Arris Glossary of Terms) F-81 This connector is used to join together two cables. Female/female splice. Also used in wallplate applications. (Arris Glossary of Terms) Fabry Perot Generally refers to any device, such as a type of laser diode that uses mirrors in an internal cavity to produce multiple reflections. (FiberOpticsInfo) Fabry–Pérot Interferometer A Fabry–Pérot interferometer consists of two parallel mirrors, allowing for multiple round trips of light. (A monolithic version of this can be a glass plate with reflective coatings on both sides.) For high mirror reflectivities, such a device can have very sharp resonances (a high finesse), i.e. exhibit a high transmission only for optical frequencies which closely match certain values. Based on these sharp features, distances (or changes of distances) can be measured with a resolution far better than the wavelength. Similarly, resonance frequencies can be defined very precisely. A modified version is the Fizeau interferometer, where the second mirror is totally reflective, and slightly tilted. The reflected light is used (e.g. with an angled beam splitter) e.g. for characterizing optical components. Another special kind of Fabry–Pérot interferometer, used for dispersion compensation, is the Gires–Tournois interferometer. (Encylopedia of Laser Physics and Technology) 
Fabry–Pérot interferometer Fabry-Perot (FP) Laser A laser oscillator in which two mirrors are separated by an amplifying medium with an inverted population, making a Fabry-Perot cavity. Standard Diode lasers are Fabry-Perot lasers. A Fabry-Perot Cavity is the standard cavity with two highly reflecting mirrors bouncing the Light back and forth, forming a standing wave. This cavity is not very Frequency selective; theoretically you could have 1 mm Wavelength light and .001 Micron wavelength light in the same cavity, as long as the mirrors are the right distance apart to form a standing wave. Fabry-Perot lasers are made with a Gain region and a pair of mirrors on the facets, but the only wavelength selectivity is from the Wavelength Dependence of the gain and the requirement for an integral number of wavelengths in a cavity round trip. A Fabry-Perot by definition consists of two planar mirrors, but the term is nowadays very frequently also used for resonators with curved mirrors. From a theoretical viewpoint, plane-plane Optical Resonators are special in the sense that their Resonator Modes extend up to the edges of the mirrors and experience some Diffraction losses. However, Fabry-Perots are usually used with input beams of much smaller diameter, which are actually not really matched to the resonator modes. For the usually small mirror spacings, where diffraction within a round trip is rather weak, this deviation does not matter that much. (Timbercon)  
FP Lasers in TO-can & FP Laser Based TOSA, courtesy of Archcom, http://www.archcomtech.com/products_2.asp Download 2.22 Mb. Share with your friends:
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