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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Types of Optical ModulatorsThere are very different kinds of optical modulators:
Bulk-optical modulators, e.g. of the electro-optic type, can be used with large beam areas, and handle correspondingly large optical powers. On the other hand, there are fiber-coupled modulators, often realized as a waveguide modulator with fiber pigtails, which can easily be integrated into fiber-optic systems. (Encylopedia of Laser Physics and Technology) Optical Overload A condition of high input current that causes pulse width distortion at the output of the transimpedance amplifier (TIA). Optical Power Refers to the average power of an optical carrier. If the optical power is gated on and off, the optical power is defined as the average power during the burst, not including turn-on and turn-off transitions. Optical power measurements are averaged sufficiently to assure that any changes to content that is modulated onto the laser does not affect the measurement. Optical Pump Laser A shorter wavelength laser used to pump a length of fiber with energy to provide amplification at one or more longer wavelengths. See also EDFA. (FiberOpticsInfo) Optical Return Loss (ORL) The ratio (expressed in dB) of optical power reflected by a component or an assembly to the optical power incident on a component port when that component or assembly is introduced into a link or system. (FiberOpticsInfo) Optical Rise Time The time interval for the rising edge of an optical pulse to transition from 10% to 90% of the pulse amplitude. Alternatively, values of 20% and 80% may be used. (FiberOpticsInfo) 
Pulse Waveform Diagram courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/o Optical Signal-to-Noise-Ratio (OSNR) The optical equivalent of SNR. (FiberOpticsInfo) Optical Spectrum The electromagnetic spectrum within the wavelength region extending from the vacuum ultraviolet at 40 nm to the far infrared at 1 mm. (Arris Glossary of Terms) Optical Spectrum Analyzer (OSA) A device that allows the details of a region of an optical spectrum to be resolved. Commonly used to diagnose DWDM systems. (FiberOpticsInfo) Optical Time Domain Reflectometer (OTDR) A fault detector that measures distance to a reflection surface by measuring the time it takes for a lightwave pulse to reflect from the surface. Reflection inter-face surfaces include the ends of cables and breaks in fiber. The reflectometer is capable of launching a pulse into a transmission medium and measuring the time required for its reflection to return by back-scattering or end reflection, thus indicating the continuity, crack, fracture, break or other features of the medium. (Arris Glossary of Terms) Optical Transmitter A device that accepts an electrical signal as its input, processes this signal, and uses it to modulate an opto-electronic device, such as an LED or an injection laser diode, to produce an optical signal capable of being transmitted via an optical transmission medium. (ITS) 
Excerpt from ANSI/SCTE 87-1 2008, “Graphic Symbols For Cable Systems Part 1: HFC Symbols”
Operating System OSA Optical Spectrum Analyzer Oscillator A circuit generating an alternating current wave at some specific frequency. (Arris Glossary of Terms) OSI Open Systems Interconnection OSI Open System Interface OSNR Optical Signal-to-Noise Ratio OSS Operation Systems Support OTA Over-the-Air OTARD Over-The-Air Reception Devices OTDR Optical Time Domain Reflectometer; an instrument that locates faults in optical fibers or infers attenuation by backscattered light measurements. (FiberOpticsInfo)  
OTL4.10 Optical Channel Transport Lane level 4 (Traverso) OTN Optical Transport Network OTP Office of Telecommunications Policy OTT Over-the-Top; unscheduled content (also known as “non-linear” programming) delivery over an otherwise unsuspecting wireline or wired network. Also defined as a general term for service that you utilize over a network that is not offered by that network operator. It's often referred to as "over-the-top" because these services ride on top of the service you already get and don't require any business or technology affiliations with your network operator. Sprint is an "over-the-top” long distance service as they primarily offer long distance over other phone company's phone lines. Often there are similarities to the service your network operator offers and the over-the-top provider offers. Over-the-top services could play a significant role in the proliferation of Internet television and Internet-connected TVs. This term has been used (perhaps incorrectly) to describe IPTV video also. (Index™) OTT TV Electronic device manufacturers are providing DVD players, video game consoles and TVs with built-in wireless connectivity. These devices piggy back on an existing wireless network, pull content from the Internet and deliver it to the TV set. Typically these devices need no additional wires, hardware or advanced knowledge on how to operate. Content suited for TV can be delivered via the Internet. These OTT applications include Facebook and YouTube. (Index™) OUI Organizationally Unique Identifier Out-of-Band Channel (OOB) An out-of-band channel is the combination of the forward and reverse out-of-band communications channels. The OOB channel provides an IP-based communication channel between the network and the digital set-top converter. Out-Of-Band-Forward-Data-Channel (OOB-FDC) The portion of the cable RF range that is used to deliver system or service information to a receiver. Its frequency range is generally 70-130 MHz. Out-Of-Band-Reverse-Data-Channel (OOB-RDC) The portion of the cable RF range that is used to deliver data from the home receiver to the headend. Its frequency range is 5-40 MHz. Output The useful power or signal delivered by a circuit or device. (Arris Glossary of Terms) Output Level The signal amplitude, usually expressed in decibel millivolts, at the output port of an active or passive device. (Arris Glossary of Terms) Output Tilt A detailed analysis of a hybrid fiber coaxial (HFC) network’s coaxial portion noise and distortion characteristics reveals that a small amount of up-slope at the optical node’s RF port downstream (DS) output is desirable. This is primarily because the maximum number of composite triple beats occurs above the arithmetic band center and up-tilt tends to equalize CTB distortion across the band. Up-tilt at the optical node DS RF output port is typically zero to three (3) dB; in bridger and line extender (LE) outputs the up-tilt is typically seven (7) to nine (9) dB. Hybrid amplifier modules employed within HFC transmission elements typically have a small amount of up-tilt. . In this case, the hybrids serve as a small portion of the up-tilt in the optical node DS RF ports. The shape of the up-tilt must be very close to the inverse shape of a high quality 0.500 inch diameter or greater coaxial cable attenuation versus frequency curve. If up-tilt shape is incorrect with respect to the inverse of coaxial cable attenuation versus frequency curve the system frequency response flatness is degraded and must be trimmed. (Hartwick) Outside Plant (OSP) In telephony, all cables, conduits, ducts, poles, towers, repeaters, repeater huts, and other equipment located between a demarcation point in a switching facility and a demarcation point in another switching facility or customer premises. (FiberOpticsInfo) 
Outside Plant Diagram courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/o Overbuilder A company that overbuilds an incumbent telecommunications operator and offers customers a competitive alternative, generally with highly advanced fiber-optic networks. See also CLEC. Overlapping Markets A case where a TV station’s Predicted Grade B Contour is overlapped by the Predicted Grade B Contour of a television station located in a different market. OVS Open Video Systems
pA picoamp; one trillionth of an Amp or 10-12 Amps. (FiberOpticsInfo) PABX Private Automatic Branch Exchange. See PBX. (FiberOpticsInfo) Packet A series of bits containing data and control information, including source and destination node addresses, formatted for transmission from one node to another. Packet Identifier (PID) A unique integer value used to identify elementary streams of a program in a single- or multi-program MPEG-2 stream. Packet Internet Grouper (PING) It is an Internet utility that verifies the connection between your computer and another IP address by sending packets to the address and checking for a response. Packet Loop A digital loop on which all information (signaling and user content) is encoded in packets. Packetized Elementary Streams (PES) An MPEG stream is composed of one or more elementary streams (ES), each containing audio, video or data. ES's can be grouped into Program Streams, which are formed by breaking ES's into chunks, the PES's, and interleaving them. Packet-switched Network (PSN) A PSN transports information by breaking up the bit stream into addressable digital “packets” that are transmitted independently and then reassembled in the correct sequence at the destination. Because these networks allow “sharing” of communications links, they are more efficient than circuit-switched networks. Packet Switching The process of routing and transferring data by means of addressed packets so that a channel is occupied during the transmission of the packet only and upon completion of the transmission the channel is made available for the transfer of other traffic. (FiberOpticsInfo) Pad A passive attenuation device used to reduce a signal's amplitude. (Arris Glossary of Terms) Pairing A partial or complete failure of interlace in which the scanning lines of alternate fields do not fall exactly between one another but tend to fall (in pairs) one on top of the other. PAL Phase Alternate Line; PAL is the standard broadcast protocol for televisions outside of North America and much of Japan. PAL is comprised of a 625 line 50-interlaced fields per second format that is used to reduce artifacts on screen (left over pixels that form objects that interfere with the picture). Phase Alternate Line is so-called because of how the chrominance signal is phase reversed on every other line, in between the spaces on an interlacing signal. (Glossary of Terms dot Net) PAPR Peak to Average Power Ratio; a comparison of the peak power detected over a period of sample time to the average power level that occurs over the same time period. (Althos) Also referred to as Crest Factor. (Wikipedia) PAR Peak-to-Average Ratio; often used interchangeably with peak to average power ratio (PAPR), or crest factor (Wikipedia) Parabola The geometric shape that has the property of reflecting the signals parallel to its axis to one point, the focal point. (Arris Glossary of Terms) Parabolic Antenna An antenna with a geometric shape that has the property of reflecting received signals parallel to its axis to a focal point and into a folded dipole or feedhorn. (Arris Glossary of Terms) Parity A term used in binary communication systems to indicate whether a number of 1’s in a transmission is even or odd. If the number of 1’s is even, the parity is said to be even; if the number of 1’s is odd, the parity is said to be odd. (FiberOpticsInfo) 
Parity Diagrams courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/p Partial Grant A grant that is smaller than the corresponding bandwidth request from the cable modem (CM). PASI Packet and Access Shelf Interface Passband The region of usable frequency in electronics or wavelength in optics. (FiberOpticsInfo) Passive Branching Device A device which divides an optical input into two or more optical outputs. (FiberOpticsInfo) 
Passive Branching Device Diagram courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/p Passive Component A component that requires no external source of power for it to function. Passive Device A circuit or network not using active devices such as tubes or transistors. A component of the broadband system which is not supplied with activating power; a device basically static in operation, that is, it is not capable of amplification or oscillation, and requires no power for its intended function. Examples include splitters, directional couplers, taps and attenuators. (Arris Glossary of Terms) Password A sequence of characters used to prevent unauthorized access to a computer or its files. It is entered along with its corresponding user ID, which are then compared against a list of authorized users before access is granted. Path Loss Actual signal attenuation from point of transmission to point of reception. (Arris Glossary of Terms) Pathological Test Code A special test pattern used with DTV and HDTV signals to create the longest strings of zeros and ones over the serial link. This requires the serial transport link to handle much lower frequency components than is typical in a normal data link. (FiberOpticsInfo) Pattern A graph type plot of receive or transmit signal characteristics by an antenna over a geographic zone or area. (Arris Glossary of Terms) Pay Cable Cable programming services for which subscribers pay an additional fee above the basic cable service charge. Also called Premium Cable. Pay Cable Unit Each premium service to which a household subscribes is counted as one unit. Pay Programming Movies, sports, and made-for-cable specials that are available to the cable customer for a charge in addition to the basic fee. Payload Header Suppression The suppression of the header in a payload packet, e.g., the suppression of the Ethernet header in forwarded packets. Payload Service Class Table (PSC) A MIB table that maps RTP Payload Type to a Service Class Name. Payload Unit Start Indicator (PUSI) A flag in an MPEG header. A value of 1 indicates the presence of a pointer field as the first byte of the payload. Pay-Per-View (PPV) An event that has an associated viewing cost, and which may be purchased separately from any package or subscription. The ordered events could include movies, special events, such as sporting, or adult programming. The event could be purchased by either impulse PPV by using a television remote (this application requires a continuous land line phone based connection), or over the phone PPV (this application may have additional costs for processing). (FiberOpticsInfo) PBX Private Branch Exchange; a subscriber-owned telecommunications exchange that usually includes access to public switched networks. (FiberOpticsInfo) PC Personal Computer PC Physical Contact; refers to an optical connector that allows the fiber ends to physically touch. Used to minimize back reflection and insertion loss. (FiberOpticsInfo) PCB Printed Circuit Board; also referred to as PWB (printed writing board). (FiberOpticsInfo)
Peripheral Component Interface PCM Pulse Code Modulation PCN Personal Communication Network PCO Private Cable Operator PCS Personal Communications Service PCS Fiber Plastic Clad Silica (FiberOpticsInfo) PD Photodiode (FiberOpticsInfo)
Protocol Data Unit PE Presentation Engine PE Professional Engineer Peak The maximum instantaneous value of a varying current or voltage. Also called crest. (Arris Glossary of Terms) Peak Power Output The output power averaged over that cycle of an electromagnetic wave having the maximum peak value that can occur under any combination of signals transmitted. (FiberOpticsInfo) Peak-to-Valley The ratio of the largest amplitude of a modulated wave to its smallest value. (Answers dot com) Peak Wavelength In optical emitters, the spectral line having the greatest output power. Also called peak emission wavelength. (FiberOpticsInfo) Peer Entities Entities within the same layer. Penetration Ratio of the number of cable customers to the total number of households passed by the system. Per Hop Behavior (PHB) In the IETF Differentiated Services (DiffServ) approach to quality of service differentiation, the treatment by a network router or switch of a group of network traffic flows for the “hop” to the next router switch. Packets “marked” or “tagged” with a common service classification in the packet header are aggregated into flow “bundles” which are treated the same, e.g., have the same priority or the same risk of being discarded in the event of network congestion. Percentage Sync The ratio, expressed as a percentage, of the amplitude of the synchronizing signal to the peak-to-peak amplitude of the picture signal between blanking and reference white level. Performance Standards The minimum technical criteria that must be met by cable television systems, consistent with standard set by the FCC or the local ordinance. Perigee The point in an elliptical satellite orbit which is closest to the surface of the earth. (Satnews) Perigee Kick Motor (PKM) Rocket motor fired to inject a satellite into a geostationary transfer orbit from a low earth orbit especially that of a STS or Shuttle-based orbit of 300 to 500 miles altitude. (Satnews) Per-Inquiry Advertising Direct response advertising for which the cable network or system running the commercial is paid based on the number of responses received rather than the air time used. Peripheral Component Interface (PCI) An interface standard for connecting hardware expansion cards to a computer. The typical PCI connection is a slot, or edge-card connector, on the computer's motherboard allowing devices such as network cards, graphics cards or drive controllers to be connected to the computer. Some PCI devices are integrated onto the motherboard, especially in the case of “brand-name” computers. PCI has eclipsed ISA as the interface of choice due to its higher transfer rate, ease of configuration and improved Plug-and-Play ability. Permanent Virtual Circuit (PVC) A point-to-point connection between two specific locations on an ATM, Frame Relay, of X.25 network. PVCs are pre-defined by the ATM, Frame Relay, or X.25 network administrator. See also SVC. Personal Communications Service (PCS) Digital networks deployed in cellular; like configuration at 1.8GHz to 2.2GHz. Personal Video Recorder (PVR) a consumer device which uses a hard disk drive to record television programs based on the user's preferences. Also provides pause of live television feature. Or a set of equipment that allows a user to timeshift television without removable media. PES Packetized Elementary Streams PES Program Elementary Stream PFM Pulse-frequency Modulation; also referred to as square wave FM. (FiberOpticsInfo) Phase A relative quantity describing the time relationship between or among waves having identical frequency. The complete wave cycle is divided into 360 equal parts, called degrees of phase. Also, the location of a position on a waveform of an alternating quality, in relation to the start of a cycle. Measured in degrees, with 360°corresponding to one complete cycle. (Arris Glossary of Terms) Phase Constant The imaginary part of the axial propagation constant for a particular mode, usually expressed in radians per unit length. See also attenuation. (FiberOpticsInfo) Phase Distortion When the output of an amplifier fluctuates in phase, even though the input does not, the circuit introduces phase distortion into the signal. Phase Jitter Phase variations arising in a channel and caused by incidental frequency modulation of signals transmitted over the channel. This occurs when the carrier supply frequencies in a frequency-division-multiplexed carrier system are not perfectly constant. Phase Lock The control of as oscillator such that its output signal maintains a constant phase angle relative to a second, reference signal. (Arris Glossary of Terms) Phase Modulation When the information is impressed on a radio frequency signal by varying its phase angle. Phase Modulator An optical modulator which can be used to control the optical phase of a laser beam. Frequently used types of phase modulators are electro-optic modulators based on Pockels cells, and liquid crystal modulators, but it is also possible to exploit thermally induced refractive index changes or length changes of an optical fiber, or induce length changes by stretching. Various kinds of phase modulators are used within the area of integrated optics, where the modulated light propagates in waveguides. Important properties of phase modulators are:
For different types of phase modulators, such properties vary in huge ranges. Therefore, different kinds of phase modulators are appropriate for different applications. Download 2.22 Mb. Share with your friends:
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