Glossary

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 0-9

Å —— angstrom

A/D —— analog-to-digital

A-GPS —— assisted GPS

AAS —— adaptive antenna systems

absorption —— The loss of light energy in an optical fiber due to impurities in the glass.

AC —— alternating current

ACM —— Association for Computing Machinery

ACM —— Adaptive Coding and Modulation, related to HSDPA.
For more information: http://www.reed-electronics.com/tmworld/article/CA6302574

ACPM —— adjacent-channel power measurement

ACPR —— adjacent-channel power ratio

active filter —— An electronic filter that combines active circuit devices, usually operational amplifiers, with resistors and capacitors. Typically, active filters more closely match ideal filters than passive filters do.

ADC —— analog-to-digital converter

ADSL —— asymmetric digital subscriber line

AES —— Audio Engineering Society

AF —— audio frequency

AFC —— automatic frequency control

AFM —— atomic force microscope

AFR —— absolute frequency reference

AGC —— automatic gain control

Ah —— ampere hours

AI —— artificial intelligence

ALC —— automatic level control

algorithm —— A set of rules with a finite number of steps for solving a problem.

alias frequency —— A false lower-frequency component that appears in analog data that is reconstructed from original data digitized at an insufficiently high sampling rate.

ALU —— arithmetic logic unit

AM —— amplitude modulation

AM/PM/VSB —— amplitude modulation/phase modulation/vestigial sideband

ambient level —— The values of signals and noise that exist at a test location when the device under test is not active.

AMLCD —— active-matrix liquid crystal display

amplitude modulation —— The process in which the amplitude of a carrier wave is varied according to a specific law.

AMPS —— advanced mobile phone system

analog-to-digital conversion —— The process that changes an analog signal into a digital magnitude value.

analog-to-digital converter (ADC or A/D converter) —— An electronic circuit that produces a digital output directly proportional to an analog signal input.

anechoic chamber —— An enclosure especially designed with walls that absorb sound or radiation, creating an essentially free-field environment for testing.

ANSI —— American National Standards Institute

antenna —— A device that radiates or receives radio waves.

anti-alias filter —— A filter that attenuates noise and high-frequency components of an analog signal prior to its conversion into a digital value.

AOI —— automated optical inspection

API —— application programming interface

AQL —— acceptance quality level

area analysis —— An image-analysis technique that finds the area in an image that falls within a range of specific gray levels.

ARINC —— Aeronautical Radio Inc.

array —— An ordered arrangement of information.

ASCII —— American (National) Standard Code for Information Interchange

ASE —— amplified spontaneous emission

ASI —— Asynchronous serial interface, a method for transferring digital TV data as a single-program TS.
For more information: http://www.reed-electronics.com/tmworld/article/CA604155

ASIC —— application-specific integrated circuit

ASP —— average selling price

aspect ratio —— The width-to-height ratio of a video picture.

ASQC —— American Society of Quality Control

assembler —— A program that translates mnemonics into binary codes that run on a computer.

asynchronous —— An action that takes place at an arbitrary time, without synchronization to a reference timer or clock.

asynchronous transfer mode (ATM) —— A fast-packet switching technology that uses asynchronous time-division multiplexing.

ATE —— automatic test equipment

ATG —— automatic test generation

ATLAS —— Abbreviated test language for avionic systems.

ATM —— asynchronous transfer mode

ATPG —— automatic test program (or pattern) generator

ATSC —— Advanced Television Systems Committee

attenuation —— The difference in a signal's voltage, current, or power from when the signal is transmitted to when it is received.

attenuation coefficient —— The rate of optical power loss with respect to distance; measured in decibels per kilometer (dB/km) at a specific wavelength.

averaging —— Mathematically smoothing the results of several measurements by adding them and dividing by the number of samples.

AWG —— (1) American wire gauge (2) arbitrary waveform generator

AWS —— Advanced Wireless Services

background —— In a personal computer, programmed operations that take place without direct operator intervention; for example, network operations, printing, and display refreshing. See also foreground.

balun —— balanced-to-unbalanced transformer

balun —— An antenna-balancing device that matches a balanced or symmetrical load (a dipole antenna) to an unbalanced load (a coaxial-cable feed line). ('Balun' is derived from 'balanced-to-unbalanced.')

band-pass filter —— A filter that passes only those signal frequencies between two set frequencies.

bandwidth (BW) —— A range of frequencies over which a system works without degrading the original signal.

bandwidth-distance product —— The information-carrying capacity of a transmission medium in units of MHz·km.

baseband —— In video and audio transmissions, a signal that is unmodulated.

BCD —— binary-coded decimal

BCH —— boradcast channel

BCI —— bulk current injection

BER —— bit error rate

BERT —— bit error rate tester

BGA —— ball-grid array

BHCA —— busy hour call attempts

BIB —— burn-in board

BIOS —— basic input-output system

bipolar —— (1) A signal that includes positive and negative values. (2) A type of semiconductor.

BIRA —— Built-in redundancy analysis.

BISDN —— broadband integrated services digital network

B-ISDN —— broadband integrated services digital network

BISR —— Built-in self-repair.

BIST —— built-in self-test

BIT —— built-in test

bit map —— A set of values that specify colors or gray levels in an image.

BITE —— built-in test equipment

blob —— A connected region in an image in which all pixels have the same gray level.

blooming —— Saturation of light-sensing elements in a TV camera. Blooming causes clipping at the camera's maximum brightness level.

BNC —— bayonet-Neill-Concelman

BP —— bandpass

bps —— bits per second

BPSK —— binary phase-shift keying

BQFP —— bumper quad flat pack

brightness —— The value associated with a pixel that represents a gray value between black and white.

broadband emission —— An emission that has a spectral energy distribution that is sufficiently broad, uniform, and continuous to ensure that a measuring receiver's response does not vary significantly when tuned over a given frequency range.

BS —— boundary scan

BSDL —— Boundary-Scan Description Language

BSI —— British Standards Institution

butterfly —— A basic math operation that forms part of a fast Fourier transform algorithm.

BW —— bandwidth

CA —— collision advance

CAD —— computer-aided design

CAE —— computer-aided engineering

CAGR —— compound annual growth rate

CAMAC —— computer-automated measurement and control

CAN —— controller area network

CAPEX —— capital expenditure

CASE —— computer-aided software engineering

CAT —— computer-aided test

CC —— constant current

CCD —— charge-coupled device

CCDF —— complementary cumulative distribution function

CCFL —— cold-cathode flourescent light

CCIR —— Comité Consultatif International des Radiocommunications (replaced by ITU-R)

CCITT —— Comité Consultatif International Télégraphique et Téléphonique (replaced by ITU-T)

cd —— candela

CDM —— charged device model

CDMA —— code-division multiple access

cdma2000 —— a proposed third-generation (3G) wireless technology that builds on cdmaOne

cdmaOne —— a code-division multiple access (CDMA) technology, embodied in the IS-95A standard

CDR —— clock-data recovery

CENELEC —— Comité Européen de Normalisation Electronique

CFC —— chlorofluorocarbon

CGC —— clock-gating cell

CGI —— common gateway interface

CGI-BIN —— common gateway interface-binary

checksum —— The sum of a group of data values. Usually transmitted with the data to assist in error detection.

chip —— a binary element of a spreading sequence, or the corresponding time interval

chrominance —— The color part of a video signal that defines the hue and saturation, but not the brightness or luminance, of the signal.

CIIL —— Common Instrument (or Control Intermediate) Interface Language

CISC —— complex instruction set computer

CISPR —— Comité International Spécial de Perturbations Radioélectriques

cladding —— The material that surrounds the core of an optical cable.

CLCC —— ceramic leaded chip carrier

CMOS —— complementary metal-oxide semiconductor

CMRR —— common-mode rejection ratio

CMV —— common-mode voltage

CMVR —— common-mode voltage ratio

CMYK —— cyan, magenta, yellow, black

COB —— chip-on-board

CODEC —— coder-decoder

codec —— An abbreviation of coder-decoder; a device that can encode and decode information.

cold-junction compensation —— An artificial reference level that compensates for ambient temperature variations in thermocouple circuits.

collimate —— To create a light beam in which all optical rays are parallel.

color bars —— Standard test pattern on a display screen of fully saturated colors (red, green, blue, magenta, cyan, and yellow) plus black and white.

COM —— common object model

common-mode rejection ratio (CMRR) —— A measure of an instrument's ability to ignore or reject interference from a signal that is common to the instrument's input terminals, but relative to ground. (Expressed in decibels.)

comparator —— A circuit that compares two signals and changes a binary output when one signal exceeds the other.

compiler —— A program that translates high-level-language statements into codes that a computer can execute.

complementary cumulative distribution function (CCDF) —— used to characterize a transmitted signal's peak-to-average power ratio vs. the probability of a particular ratio's occurrence

composite sync —— A video signal that contains horizontal-sync pulses, vertical-sync pulses, and equalizing pulses only, with a no-signal reference level.

composite video —— A signal composed of luminance (black and white), chrominance (color), blanking pulses, sync pulses, and a color-burst signal.

conducted emission —— Electromagnetic energy that is propagated along a conductor. This energy is called 'conducted interference' if it is undesired.

contrast —— A measure of brightness content in an image. High contrast implies mainly dark-black and bright-white content; low contrast implies a small spread of gray values.

conversion time —— The time required from the moment a channel is interrogated to the moment that accurate data is available. Usually associated with DACs and ADCs.

convolution —— The integration of the product of two functions in time. Convolution in the time domain is equivalent to multiplication in the frequency domain.

Coordinated Universal Time or Universal Time Coordinated —— A coordinated time scale that forms the basis of a coordinated dissemination of standard frequencies and time signals.

coprocessor —— A processor that operates with the CPU to boost speed. For example, a digital signal processing (DSP) chip can free the CPU from having to perform repetitious math operations.

COTS —— commercial off-the-shelf

counter —— (1) In software, a memory location used to store a count of certain occurrences. (2) In hardware, a circuit that counts events. See also event counter.

counterpoise —— The reference-plane portion (grounded or ungrounded) of an unbalanced antenna.

CPE —— customer premises equipment

CPLD —— complex PLD

cps —— cycles per second

CPS —— characters per second

CPU —— central processing unit

CQFP —— ceramic quad flat pack

CRC —— cyclic redundancy check

CRM —— Customer relationship management.

cross assembler —— A program that runs on one computer and generates instructions for another type of computer.

cross coupling —— The coupling of a signal from one channel, circuit, or conductor to another, where it becomes an undesired signal.

cross modulation —— Modulation of a desired signal by an undesired signal. This is a special case of intermodulation. See also intermodulation.

crosstalk —— A phenomenon in which one or more signals interfere with another signal.

crowbar —— An overvoltage protection method which shorts the power supply output to ground in order to protect the load when an overvoltage fault is detected.

CRT —— cathode ray tube

CSA —— Canadian Standards Association

CSMA/CA —— carrier sense multiple access with collision avoidance

CSMA/CD —— carrier sense multiple access/collision detection

CTE —— coefficient of thermal expansion

CTL —— Core Test Language as defined in the IEEE 1450.6 standard and derived from the IEEE 1500 standard.
For more information: http://www.reed-electronics.com/tmworld/article/CA218789.html

CTS —— clear-to-send

current loop —— A communications method that transmits data as current flow over relatively long distances and through environments with relatively high noise.

CV —— constant voltage

CVU —— capacitance-voltage unit

CW —— continuous wave

cyclic redundancy check (CRC) —— a mathematically generated number that data receivers use to verify the proper bit arrangement in a bit stream.

D/A —— digital-to-analog

D8PSK —— differential 8-phase phase-shift keying

DAC —— digital-to-analog converter

DAP —— data-acquisition processor

DAQ —— data acquisition

DAS —— data-acquisition system

data acquisition (DAQ) —— Gathering information from sources such as sensors and transducers.

dB —— decibel

dBa —— decibels adjusted

dBa0 —— noise power measured at zero transmission level point

dBc/Hz —— level difference referred to carrier level calculated for a measurement bandwidth of 1 Hz. (Spectrum and network analysis.)

dBfs —— decibels full scale

dBm —— dB referred to 1 milliwatt

dBm (psoph) —— noise power in dBm measured by a set with psophometric weighting

dBm0 —— noise power in dBm referred to or measured at 0TLP

dBm0p —— noise power in dBm measured by a psophometric or noise measuring set having psophometric weighting

dBmV —— dB referred to 1 millivolt across 75 ohms

DBPSK —— differential-binary phase-shift keying

dBr —— power difference in dB between any point and a reference point

dBrn —— dB above a reference noise

dBrn(f1f2) —— flat noise power in dBrn

dBrnC —— noise power in dBrn measured by a set with C-message weighting

dBrnC0 —— noise power in dBrnC referred to or measured at 0TLP

DBS —— direct broadcast satellite

dBV —— dB relative to 1 V (volt) peak-to-peak

dBW —— dB referred to 1 W (watt)

dBx —— dB above reference coupling

DC —— direct current

DCA —— direct chip attach

DCE —— data communications equipment

DCS —— digital cellular service

DCT —— discrete cosine transform

DDE —— dynamic data exchange

DDR —— double data rate (refers to a type of SDRAM)

DDR2 —— double data rate

DDS —— direct digital synthesis

decibel (dB) —— A logarithmic measure of the ratio of two signal levels: dB = 20 log (Voltage1 / Voltage2) and dB = 10 log (Power1 / Power2). Variants on the decibel (dB) used in spectrum-analysis and network-analysis measurements are dBmV (absolute voltage level referr

decoupling-network —— An electrical circuit that prevents test signals that are applied to the unit under test from affecting other devices, equipment, or systems that are not under test.

DECT —— digital European cordless telecom

degradation —— An unwanted change in the performance of a system undergoing testing. A degradation is not necessarily a malfunction or failure.

DES —— Data Encryption Standard

design rules —— Allowable dimensions used in the layout and design of an integrated circuit. Such rules are specific to different types of ICs.

device driver —— See driver.

DFB —— distributed feedback

DFM —— design for manufacturability

DfR —— design-for reliability

DFT —— (1) design for test (2) discrete Fourier transform

DGPS —— differential GPS

DIB —— device interface board (a load board or DUT board)

DigRF —— Digital Radio Frequency

digital-to-analog conversion —— The process that changes discrete values into a voltage or current.

digital-to-analog converter (DAC or D/A converter) —— A device that converts digital information into a corresponding analog voltage or current.

DIMM —— dual in-line memory module

DIN —— Deutsches Institut fur Normung (German Institute for Standards)

DIP —— dual in-line package

dipole —— An antenna made of a straight conductor (usually not longer than half a wavelength) that is divided at its electrical center and connected to a transmission line.

direct memory access (DMA) —— The direct transfer of information between a computer's memory and a device while the computer's CPU does something else.

discrete cosine transform —— A mathematical operation that compresses video data in JPEG and MPEG files.

DLL —— dynamic link library

DLLP —— data-link layer packet

DMA —— direct memory access

DMB-T —— Digital Multimedia Broadcast Technology, a Chinese standard for digital television

DME —— distance measuring equipment

DMM —— digital multimeter

DMR —— digital mobile radio

DNL —— differential nonlinearity

DNS —— Domain Name System

DOS —— disk operating system

downlink —— a transmission from a base station to a mobile unit

DPCH —— Dedicated Physical Channel.

DPM —— (1) digital panel meter (2) defects per million (3) direct part marketing

DPSK —— differential phase-shift keying

DPX —— digital phosphor display

DQPSK —— differential-quadrature phase-shift keying

DRAM —— dynamic random access memory

DRDRAM —— Direct RAMBUS DRAM

driver —— Software that controls a specific hardware device, such as a data-acquisition board or a printer.

DSL —— digital subscriber loop

DSO —— digital sampling (or storage) oscilloscope

DSP —— digital signal processor (or processing)

DSSS —— direct-sequence spread spectrum

DTE —— data terminal equipment

DTMF —— dual-tone multiple frequency

DUT —— device under test

DVB-H —— Digital Video Broadcast-Handheld
For more information: http://www.reed-electronics.com/tmworld/article/CA604155

DVB-T —— Digital Video Broadcast-Terrestrial
For more information: http://www.reed-electronics.com/tmworld/article/CA604155

DVD —— digital versatile disk

DVI —— digital visual interface

DVM —— digital voltmeter

DWT —— discrete wavelet transform

dynamic range —— The ratio of the full-scale range (FSR) of a data converter to the smallest difference the converter can resolve. (Dynamic range is generally expressed in decibels.)

EDA —— electronic design automation

EDFA —— erbium-doped fiber amplifier

EDGE —— enhanced data rates for GSM evolution

edge detection —— A technique that locates an edge by examining an image for abrupt changes in pixel values. See also image processing.

EDID —— extended display identification data

EDIF —— Electronic Design Interchange Format

EDO —— extended data out (RAM)

EEPROM —— electrically erasable programmable read-only memory

EFT —— electrical fast transient

EIA/J —— Electronic Industries Association

EISA —— extended ISA (PC bus)

EL —— electroluminescent

electromagnetic compatibility (EMC) —— (1) The ability of electronic equipment to operate in an intended electromagnetic environment without degradation caused by interference. (2) The ability of equipment to operate in its electromagnetic environment without creating interference with other e

ELF —— extremely low frequency (&3 kHz)

EMC —— electromagnetic compatibility

emf —— electromotive force

EMF —— electromagnetic field

EMI —— electromagnetic interference

EMP —— electromagnetic pulse

EMR —— electromagnetic radiation

EN —— Norme Europeenne (European standard)

ENI —— equivalent noise input

EO —— electro-optical (or -optic)

ephemeris time —— An astronomical time scale based on the orbital motion of the earth around the sun.

EPLD —— erasable programmable logic device

EPP —— enhanced parallel port

EPROM —— erasable programmable read-only memory

ERP —— effective radiated power

ERP/MRP —— Enterprise resource planning/materials requirements planning

ESD —— electrostatic discharge

ESR —— equivalent series resistance

ESS —— (1) environmental stress screening (2) electronic switching system

ETS —— equivalent time sampling

ETSI —— European Telecommunications Standards Institute

EU —— European Union

EUT —— equipment under test

eV —— electron volt

event counter —— A circuit that counts the occurrences of a certain condition. See also counter.

EVM —— error-vector magnitude

F/V —— frequency-to-voltage

FA —— failure analysis

false color —— Color added to an image to call attention to details that aren't readily perceptible or to create special effects.

far field —— The region in which the power flux density from an antenna obeys the inverse-square law. For a dipole antenna, distances beyond l/2 are far-field regions.

FC —— fiber channel

FCC —— Federal Communications Commission

FDDI —— fiber distributed data interface

FDM —— frequency-division multiplexing

FDMA —— frequency-division multiple access

feature —— In inspection, any characteristic of an image or a region in an image.

feature extraction —— A technique that generates a set of descriptors or characteristic attributes from a binary image.

FEC —— forward error correction

FEC —— Forward-error correction, an algorithm to correct transmission errors on the receiving end.

FET —— field-effect transistor

FFT —— fast Fourier transform

FIB —— focused ion beam

Fibre Channel ——

field —— (1) The set of either the even or odd lines in an interlaced video image. The concept of a field is used when dealing with an interlaced video display. (2) A large open site at which testing can take place.

field of view —— The area of the object under view as represented at the focal plane of a camera.

field strength —— The measurement of either the electric field or the magnetic field that is made in the far field. (Expressed in units of V/m, A/m, or W/m.)

FIFO —— first-in, first-out

file transfer protocol (FTP) —— A protocol that transfers files over the Internet.

filter —— An operation that selectively removes noise from a signal. Electronic filters include low-pass, band-pass, and high-pass types. Mathematical filters can operate on data to extract information and to enhance images.

FIR —— finite impulse response

firewall —— Hardware or software that protects a network from unauthorized access.

firmware —— A program permanently recorded in ROM; it is effectively a piece of hardware that performs software functions.

FIT —— (1) fault isolation test (2) failures in time

flaw detection —— An image-analysis technique that examines an object for unwanted features of unknown shapes at unknown positions.

FM —— frequency modulation

FMC —— fixed-mobile convergence

FO —— fiber-optic

foreground —— In a personal computer, the activity subject to direct operator intervention. Background activities may be running on the computer simultaneously.

forward channel —— the channel used for downlink transmissions

FPGA —— field-programmable gate array

FQFP —— fine-pitch quad flat pack

frame —— In inspection, the total area of the picture that is scanned by a camera.

frame grabber —— A device that digitizes an image and stores it in a computer's memory.

frame rate —— The frequency at which an image is completely updated on a display monitor.

frame relay —— A technology for transmitting data packets in high-speed bursts across a digital network.

frequency standard —— A precise frequency generator such as a rubidium, cesium, or hydrogen maser whose output is used as a frequency.

FRU —— field replaceable unit

FS —— full scale

FSK —— frequency-shift keying

ftp —— file transfer protocol

FWM —— four-wave mixing

GenICam —— GENeric programming Interface for CAMeras.
For more information: http://www.genicam.org

genlock —— Extraction of horizontal-sync and vertical-sync signals from a video signal and the use of those signals to synchronize video equipment.

GFSK —— Gaussian frequency-shift keying

GIF —— graphic interchange file

Global System for Mobile Communications (GSM) —— A pan-European standard for digital cellular radio. Originally known as Groupe Spéciale Mobile.

GMSK —— Gaussian-filtered minimum-shift keying

GPIB —— general purpose instrument bus

GPRS —— general packet radio service; a standard for wireless data transmission

GPS —— Global Positioning System (or Satellite)

graded-index fiber —— An optical fiber in which the refractive index increases toward the center of the fiber.

gray level —— The brightness value assigned to a pixel; values range from black, through gray, to white.

gray scale —— The discrete gray levels that are defined for an imaging system or imaging software. In an eight-bit system, the gray scale runs from 0 to 255.

ground —— (1) An electrically neutral wire that has the same potential as the surrounding earth. Normally, a non-current-carrying circuit intended for safety. (2) A common reference point for an electrical system.

ground loop —— An unintentionally induced feedback loop caused by two or more circuits sharing a common electrical ground.

ground plane —— A conducting surface or plate used as a common electrical reference point for circuits.

GSM —— Global System for Mobile Communications (originally Groupe Speciale Mobile)

GT/s —— Gigatransfer per second

GTEM —— gigahertz transverse electromagnetic mode

GUI —— graphical user interface

HALT —— highly accelerated life test

hard hand-off —— a break-before-make transfer of a mobile phone’s link from one base station to another

harmonic distortion (HD) —— A form of distortion in analog circuits that generates harmonics (signals whose frequencies are integer multiples of the input signal). It is calculated as the ratio of a single harmonic to the level of the original signal. Harmonic distortion is related

HARQ —— Hybrid Automatic Repeat Request, related to HSDPA.
For more information: http://www.reed-electronics.com/tmworld/article/CA6302574

HASS —— highly accelerated stress screening

HAST —— highly accelerated stress test

HBM —— human body model

HCFC —— hydrogenated chlorofluorocarbon

HD —— harmonic distortion

HDL —— hardware description language

HDMI —— high-definition multimedia interface

HDSL —— high-bit-rate digital subscriber line

HDTV —— high-definition television

HDVI —— high density voltage/current

hexadecimal —— The base-16 numbering system.

HF —— high frequency (3 MHz to 30 MHz)

high-pass filter —— (1) A math operation that emphasizes details in an image. (2) A circuit that attenuates low-frequency components in an analog signal.

HIL —— hardware-in-the-loop

hipot —— high-potential

histogram —— In inspection, the graphical representation of the gray-scale values found in an image.

horizontal blanking —— The blanking signal that occurs at the end of each video scanning line.

horizontal sync —— The portion of a video signal that indicates the end of a line of video information.

HPA —— high-power amplifier

HPSK —— hybrid phase-shift keying

HSDPA —— High-Speed Downlink Packet Access, a data-transmission technology that has evolved from WCDMA.
For more information: http://www.reed-electronics.com/tmworld/article/CA6302574

HS-DSCH —— High-Speed Downlink Shared Channel, HSDPA's 'fat pipe.'
For more information: http://www.reed-electronics.com/tmworld/article/CA6302574

HSUPA —— High Speed Uplink Packet Access.

HTML —— hypertext markup language

HTOL —— high-temperature operating life

http —— hypertext transfer protocol

hue —— The distinction between colors. Red, blue, green, and yellow are examples of hues. White, black, and gray are not considered hues because they are intensities, not colors.

HV —— high voltage

hypertext transfer protocol (http) —— The protocol that negotiates document delivery to a Web browser from a Web server.

Hz —— hertz

I/O —— input/output

I/O address —— A specific hardware circuit and software value that the CPU uses to distinguish between the different boards in a system.

I/Q —— in-phase/quadrature

IA —— instrumentation amplifier

IBIS —— input output buffer information specification

IBIST —— interconnect built-in self-test

IC —— integrated circuit

ICE —— in-circuit emulator

ICT —— in-circuit test

IDC —— insulation displacement connector

IDDQ —— Semiconductor device quiescent current.
For more information: http://www.reed-electronics.com/tmworld/article/CA331921

IEC —— International Electrotechnical Commission

IEE —— Institution of Electrical Engineers (UK)

IEEE —— Institute of Electrical and Electronics Engineers
For more information: http://www.ieee.org

IES —— Institute of Environmental Sciences

IF —— intermediate frequency

IFT —— inverse fast Fourier transform

IGBT —— insulated (or isolated) gate bipolar transistor

IIR —— infinite impulse response

image analysis —— A technique that extracts features and descriptions from images.

image processing —— Transforming a source image into an improved image that supplies specific properties. For example, edge detection is an image-processing method.

IMAPS —— International Microelectronics and Packaging Society

IMD —— intermodulation distortion

immunity —— The property of a piece of equipment that enables it to reject an electrical disturbance.

impulse —— An electromagnetic pulse of short duration--shorter than one cycle at the highest frequency being considered.

IMS —— Internet protocol multimedia subsystem

iNEMI —— The International Electronics Manufacturing Initiative, an industry-led consortium of approximately 70 electronics manufacturers, suppliers, and related organizations.
For more information: http://www.inemi.org

INL —— integral nonlinearity

instrumentation amplifier (IA) —— An amplifier circuit with high-impedance differential inputs and high common-mode rejection.

intermodulation —— The mixing of two signals in a nonlinear device. This produces signals at frequencies that are the sum and difference of integral multiples of the original signals. See also cross modulation.

interpreter —— A program that translates high-level-language instructions, one at a time, into computer code. The computer runs the resulting code as soon as the interpreter translates individual instructions. Examples include dialects of Basic.

interrupt —— A signal that requires immediate attention from a computer's CPU.

interrupt handler —— The software routine that handles an interrupt's request for service.

interrupt vector —— A type of interrupt that immediately points a computer to a new series of instructions. See also interrupt.

IP —— (1) Internet protocol (2) intellectual property

IPC —— Institute for Interconnecting and Packaging Electronic Circuits

IPI —— intelligent peripheral interface

IR —— (1) infrared radiation (2) insulation resistance

IRQ —— interrupt request

ISA —— (1) Instrument Society of America (2) Industry Standard Architecture

ISDN —— integrated services digital network

ISO —— International Organization for Standardization

isolation amplifier —— An amplifier that provides electrically isolated inputs and outputs that let it amplify a differential signal that is superimposed on a high common-mode voltage.

isolation voltage —— The voltage that an isolated circuit can normally withstand. Isolation voltage is specified from input to input or from any input to the amplifier output.

isotropic —— Having properties that have equal value in all directions.

ISP —— in-system programmable

ISR —— interrupt service routine

ITS —— Institute for Telecommunication Sciences

ITU —— International Telecommunications Union

ITU-R —— ITU radio communications unit

ITU-T —— ITU telecommunications unit

IVI —— Interchangeable Virtual Instrument

Java —— A subset of the C++ language specifically meant for running applications on the Web.

JEDEC —— Joint Electron Device Engineering Council

JEDEC —— The JEDEC Solid State Technology Association (once known as the Joint Electron Device Engineering Council).
For more information: http://www.jedec.org/

JET —— JTAG Emulation Test

JIT —— just in time

JPEG —— Joint Photographic Experts Group

JTAG —— Joint Test Action Group

Julian day —— Obtained by counting days from the starting point of noon on 1 January 4713 B.C. (Julian Day zero). One way of telling what day it is with the least possible ambiguity. The Julian Date but may be used in other contexts.

KGD —— known-good die

LAN —— local area network

laser —— light amplification by stimulated emission of radiation

LAT —— Local area transport, a proprietary Digital Equipment Corp. (now part of Hewlett-Packard) protocol used to transfer data to and from Digital hosts

LCC —— leadless chip carrier

LCCC —— leadless ceramic chip carrier

LCD —— liquid crystal display

LCT —— logical channel type

leap second —— An intentional time step of one second used to adjust UTC to ensure approximate agreement with UT1 (see Julian day). An inserted second is called a positive leap second, and an omitted second is called a negative leap second.

LED —— light-emitting diode

LF —— low frequency (30 kHz to 300 kHz)

LFE —— low-frequency effects

LFSR —— Linear feedback shift register, a circuit that can be used in test-pattern generation.

LGA —— land-grid array

LIF —— low-insertion force

LIN —— local interconnect network, a serial communication system for distributed electronic systems in vehicles.

line —— In imaging, the coordinate that defines the vertical location of a pixel in an image.

linearity —— The relationship of a device's response to a straight line.

LNA —— low-noise amplifier

LO —— local oscillator

low-pass filter —— (1) A circuit that attenuates the high-frequency components in an analog signal. (2) An operation that blurs details in an image.

LRM —— long-reach multimode

LRU —— line replaceable unit

LSB —— (1) least significant bit (2) lower sideband

LSI —— large-scale integration

LTE —— long term evolution

luminance —— The brightness or intensity of a color.

LUT —— look-up table

MAC-hs —— Medium Access Control high-speed, related to HSDPA.
For more information: http://www.reed-electronics.com/tmworld/article/CA6302574

macro —— A set of program steps combined by a user or a programmer that act as a single and more powerful program step.

MATE —— modular automatic test equipment

MCC —— Microelectronics and Computer Technology Corporation (formerly Microelectronics and Computer Consortium)

MCM —— multichip module

Mcps —— megachips per second

MCU —— microcontroller units

MDA —— manufacturing defects analyzer

MEMS —— microelectromechanical systems

MES —— Manufacturing execution system.

MFP —— mini flat pack

MIME —— multipurpose (or multimedia) Internet mail extension

MIMO —— multiple-input multiple-output

MIPI —— Mobile Industry Processor Interface

mismatch —— A nonideal coupling of two circuits. The part of the signal that does not pass through the coupling gets reflected and leads to measurement error.

MMIC —— monolithic microwave integrated circuit

monochrome —— An image represented by a single color. Generally, a monochrome image is presented as white on a black background.

monopole —— An antenna that consists of a straight conductor and is usually not more than one quarter of a wavelength long. A monopole is mounted immediately above, and at a right angle to, a ground plane.

monotonicity —— A characteristic of a properly operating DAC in which the analog output increases as the digital code input to it increases.

MOSFET —— metal-oxide semiconductor field-effect transistor

MPE —— Multiprotocol encapsulation, which includes methods to encode an IP datagram stream onto a TS.
For more information: http://www.reed-electronics.com/tmworld/article/CA604155

MPE-FEC —— Multiprotocol encapsulation forward-error correction.
For more information: http://www.reed-electronics.com/tmworld/article/CA604155

MPEG —— Moving (or Motion) Picture Experts Group

MPI —— main path interface; multipath interface

MPI-R —— main path interface at the receiver

MPI-S —— main path interface at the transmitter

MPU —— microprocessor (or microprocessing) unit

MPV —— multi-programmable/multi-voltage

MRC —— maximum ratio combining

MSB —— most significant bit

MSI —— medium-scale integration

MSK —— minimum-shift keying

MTBF —— mean time between failures

MTTF —— mean time to failure

MTTR —— mean time to repair

multiplexer (MUX) —— A set of semiconductor or electromechanical switches arranged to select one of many inputs to a single output.

MUX —— multiplexer

MWM —— multiwavelength meter

MXI —— multiplatform extension for instrumentation

NCSL —— National Council of Standards Laboratories

NEMA —— National Electrical Manufacturers Association

NEP —— noise equivalent power

NF —— noise figure

NIC —— network interface card

NiCD —— nickel-cadmium

NIST —— National Institute of Standards and Technology

NMRR —— normal-mode rejection ratio

noise —— Undesirable electrical interference to a signal.

noise distortion —— The nonlinear behavior that circuits or devices exhibit when driven with a broadband noise signal.

noise floor —— (1) The level below which no information can be obtained from a signal. A signal that occurs below a noise floor is permanently lost. (2) The minimum discernible signal that can be detected by a receiver.

NRE —— nonrecurring engineering

NRZ —— nonreturn to zero

NRZI —— nonreturn to zero inverted

ns —— nanosecond

NTC —— negative temperature coefficient

NTSC —— National Television System Committee

NTSC (National Television System Committee) —— A 60-Hz standard for encoding color video signals. The standard is used in North America, Canada, Japan, and most of South America. See also PAL, RS-170.

NVLAP —— National Voluntary Laboratory Accreditation Program

NVNA —— nonlinear vector network analyzer

Nyquist sampling theorem —— A theorem that states that if you sample a signal at rate f, the sampled signal will contain no information about signals with frequency components above f/2.

OA —— optical amplifier

OCX —— OLE control

ODM —— original design manufacturer

OE —— opto-electric

OEM —— original equipment manufacturer

ofdm —— orthogonal frequency division multiplexing

off-hook —— in telephony, the situation that exists when a telephone handset is in use--it is 'off the hook'.

OLE —— object linking and embedding

OLED —— organic light-emitting diode

on-hook —— in telephony, the situation that exists when a telephone handset is not in use--it is 'on the hook'.

OOP —— object oriented programming

open area —— An open and flat test site at which electromagnetic-interference measurements are taken and at which effects from power wires, buildings, and underground cables are negligible. Ambient radiation must be low enough to permit testing.

optical isolator —— A device that links two circuits through an optoelectronic transmitter and receiver with no direct electrical connection between the two circuits.

OQPSK —— offset-quadrature phase-shift keying

OS —— operating system

OSC —— optical supervisory channel

OSNR —— optical signal-to-noise ratio

OTA —— over-the-air

OTDR —— optical time-domain reflectometer

OVP —— overvoltage protection

PA —— power amplifier

PAL —— (1) programmable array logic (2) phase alternation line

PAL (phase alternation line) —— A 50-Hz composite color video standard used in Western Europe, India, China, and some Middle Eastern countries. See also NTSC, RS-170.

palette —— The range of colors that a display can produce.

PAPR —— peak to average power ratio

passive filter —— A filter circuit using only passive components such as resistors, capacitors, and inductors.

PBX —— private branch exchange

PC Card —— The name of version 3.0 of the PCMCIA form factor.

PCB —— printed circuit board

PCI —— Peripheral Component Interconnect

PCIe —— PCI Express

PCM —— pulse code modulation

PCMCIA —— Personal Computer Memory Card International Association

P-Code —— precise code

PDH —— plesio-synchronous digital hierarchy

PF —— power factor

PGA —— pin-grid array

PHY —— physical layer interface

pigtail —— A fiber-optic cable that has a connector installed on one end.

PIND —— particle impact noise detection

pitch —— The center-to-center distance between adjacent leads on a device or package.

PIV —— peak inverse volts (or voltage)

pixel —— (1) The fundamental picture element in a digital image. (2) The coordinate unit used to define the horizontal location of a pixel in an image. ('Pixel' is an acronym for 'picture element.')

PLA —— programmable logic array

PLCC —— plastic leaded chip carrier

PLD —— programmable logic device

PLL —— phase-locked loop

PM —— (1) pulse modulation (2) phase modulation

PMC —— PCI Mezzanine Card

PMD —— polarization mode dispersion

PMI —— Probe mark inspection.
For more information: http://www.reed-electronics.com/tmworld/article/CA6338187.html

PN —— pseudonoise

PoCL —— Power over Camera Link

PoE —— Power over Ethernet

polarization —— The orientation of the field vector in a radiated field.

polling —— A round-robin canvassing of inputs to a computer to determine which ones are active. In most cases, polling is synchronized in software to a clock or external trigger.

port —— A communications connection on a computer or a remote controller. For example, an I/O port.

POST —— power-on self-test

POTS —— plain old telephone service (or system)

p-p —— peak-to-peak

ppm —— parts per million

pps —— pulses per second

PQFP —— plastic quad flat pack

PRBS —— pseudorandom bit sequence

PRF —— pulse repetition frequency

primary frequency standard —— A standard whose frequency corresponds to the adopted definition of the second with its specified accuracy achieved without external calibration of the device. Currently, only the cesium frequency standard is defined as a primary standard.

PRN —— pseudorandom noise

PROM —— programmable read-only memory

PSD —— power spectral density

pseudonoise (PN) —— in CDMA technology, random digital sequences used to spread the spectrum of a digital uplink baseband message signal

PSI/SI —— Program specific information, data required by a receiver to de-multiplex and decode the various programs in a TS.
For more information: http://www.reed-electronics.com/tmworld/article/CA604155

PSK —— phase-shift keying

PSTN —— public switched telephone network

PTP —— Precision Time Protocol

PWB —— printed wiring board

PWM —— pulse-width modulation

QA —— quality assurance

QAM —— quadrature amplitude modulation

QC —— quality control

QCPM —— quadrature continuous phase modulation

QFN —— Quad-flat-pack no-lead package.

QFP —— quad flat pack

QML —— qualified manufacturers list

QoE —— Quality of Experience

QoS —— Quality of Service

QPL —— qualified parts (or products) list

QPSK —— quadrature phase-shift keying

quantizing error —— The inherent uncertainty in digitizing an analog value that is caused by the finite resolution of the conversion process. Increasing the resolution of an ADC reduces the uncertainty.

R/W —— read/write

radio-frequency interference (RFI) —— High-frequency interference with radio reception.

RAM —— random access memory

range —— The maximum and minimum allowable full-scale signal (input or output) that yields a specified performance level.

RBW —— resolution bandwidth

RC —— (1) resistor-capacitor (2) remote control (3) radio-controlled

RCVR —— receiver

reflectance —— The ratio of power reflected to the incident power at a connector junction or other component or device, usually measured in dB.

region of interest —— In inspection, the area inside defined boundaries of an image that you want to analyze.

repeatability —— The ability of an instrument to give the same output or reading under repeated identical conditions.

resolution —— (1) The smallest division to which a measurement can be determined. For example, an ADC with 12-bit resolution can resolve 1 part in 4096 (212) over its input range. (2) In inspection: (a) a measure of the spatial resolution of either a camera or a displ

reverse channel —— the channel used for uplink transmissions

RF —— radio frequency

RFI —— radio-frequency interference

RFID —— radio-frequency identification

RGB —— red-green-blue

RGB (red-green-blue) —— A video-display standard in which three separate signals--red, green, and blue--transmit image information.

RH —— relative humidity

RIMM —— Trademark for Direct Rambus memory module

RISC —— reduced instruction set computer (or computing)

RJ-11 —— four-wire phone-line connector

RJ-45 —— eight-wire phone-line connector

RMS —— root-mean-square

RoHS —— Restriction of use of Hazardous Substances.
For more information: http://www.reed-electronics.com/tmworld/article/CA6311821.html

ROM —— read-only memory

RS-170 —— The encoding standard for 60-Hz black-and-white television signals; it is used as the standard for most monochrome video equipment. See also NTSC, PAL.

RS-343 —— Similar to RS-170, but this encoding standard provides high-resolution color information for computer video applications.

RSS —— root summed square (in circuit simulation, a statistical method of determining the effects of component tolerances on an output signal level)

RT —— (1) real time (2) risetime

RTCP —— real-time transport control protocol

RTD —— resistance temperature detector

RTL —— register transfer level

RTOS —— real-time operating system

RTP —— real-time transport protocol

S/H —— sample and hold

S/N —— signal-to-noise

SA —— spectrum analyzer

SAE —— Society of Automotive Engineers

salicide —— a self-aligned silicide; a silicon or polysilicon reaction with a metal that forms a new compound self-aligned to the device component structure, such as the gate, source, and drain regions. (Definition obtained from Sematech, www.sematech.org.)

sample and hold (S/H) —— A circuit that acquires an analog voltage and stores it temporarily in a capacitor. This circuit is also referred to as a sample-and-hold amplifier (SHA).

SAN —— storage area network

SAW —— surface acoustic wave

SBC —— single-board computer

SBS —— stimulated Brillouin scattering

SCFM —— standard cubic feet per minute (i.e., at room temperature and pressure)

SCPI —— Standard Commands for Programmable Instruments

SCSI —— Small Computer Standard Interface

SDH —— synchronous digital hierarchy

SDK —— software development kit

SDRAM —— synchronous dynamic random access memory

SECAM —— System Electronique Couleur avec Memoire

SECAM —— sequential color and memory, a video standard used in China, Russia, and France.

second —— The basic unit of time which equals 9,192,631,770 periods of radiation corresponding to the transition in cesium-133 atoms as defined at the 1967 Conference Generale des Poids et Mesures.

Seebeck effect —— The principle that describes how thermocouples work. A thermocouple circuit contains two junctions of two dissimilar metals. When the junctions are at different temperatures, a current flows.

SEM —— scanning electron microscope

SEMI —— Semiconductor Equipment and Materials International Association
For more information: http://www.semi.org/

sensitivity —— A measure of the minimum change in an input signal that an instrument can detect.

settling time —— The time required, after rapidly changing a circuit's input signal, for that circuit's output voltage to settle and remain within a specified error band around the final value.

SFDR —— spurious-free dynamic range

SFN —— Single-frequency network.

SFP+ —— Small Form-Factor Pluggable

shmoo plot —— A graph of pass/fail test results that plots pairs of test criteria such as frequency vs. voltage, or voltage vs. temperature. The shapes of such plots may resemble (roughly) the ghost-like Shmoo character introduced to the Li'l Abner cartoon strip by Al

SI —— International System of Units

SIA —— Semiconductor Industry Association

SID —— Society for Information Display

sidereal time —— The measure of time related to the stars rather than to the sun.

signal-to-noise ratio (SNR) —— The ratio of total signal to noise expressed in decibels (dB). The larger the number, the better. SNR is calculated by SNR = 20 log (SignalRMS / NoiseRMS). A related unit is the signal-to-noise-and-distortion ratio (SINAD), the ratio of the input signal

silicide —— a silicon or polysilicon reaction with a metal to form a new compound. (Definition obtained from Sematech, www.sematech.org.)

SIMM —— single in-line memory module

simultaneous sample and hold —— A data-acquisition technique in which several sample-and-hold circuits sample several different analog channels simultaneously.

SINAD —— (signal+noise+distortion)/(noise+distortion)

SIP —— single in-line package

skew —— Any observed difference in time between two events that occur simultaneously.

SLA —— Service Level Agreement

SLAM —— scanning laser acoustic microscope

SLIC —— subscriber-line interface circuit

SMART —— (1) stress marginality and accelerated reliability testing (2) standard module avionic repair and test

SMC —— surface-mount component

SMD —— surface-mount device

SMEMA —— Surface-Mount Equipment Manufacturers Association

SML —— Semantic markup language.

SMS —— short message service

SMT —— surface-mount technology

SMTA —— Surface-Mount Technology Association

SNR —— signal-to-noise ratio

SOAP —— Simple Object Access Protocol.

SOC —— system on a chip

soft hand-off —— a make-before-break transfer of a mobile phone from one base station to another

SOIC —— small-outline integrated circuit

SOJ —— small-outline integrated circuit with J leads

SONET —— synchronous optical network

SOP —— small-outline package

SOT —— small-outline transistor

S-parameters —— scattering parameters

SPC —— statistical process control

SPDT —— single-pole, double-throw

SPI —— serial peripheral interface

SPICE —— simulation program with integrated circuit emphasis

spike —— A transient disturbance of an electrical circuit caused by, for example, load variations on the AC power line.

SPM —— scanning probe microscope

SPM —— self-phase modulation

spreading rate 1 (SR1) —— the basic chip spreading rate of 1.2288 Mcps for cdma2000

spreading rate 3 —— three times spreading rate 1 (SR1)

SPST —— single-pole, single-throw

SQC —— statistical quality control

SQPSK —— staggered-quadrature phase-shift keying

SR1 —— spreading rate 1

SR3 —— spreading rate 3

SRAM —— static random access memory

SSA —— Single-stuck-at, a fault model that represents circuit nets stuck at logic 1 or 0 states.
For more information: http://www.reed-electronics.com/tmworld/article/CA187329.html

SSB —— single sideband

SSOP —— shrink small-outline package

stability —— The ability of an instrument or sensor to maintain a consistent output when a constant input is applied.

STC —— space time coding

STEM —— scanning transmission electron microscope

STIL —— The Standard Test Interface Language, defined in the IEEE 1450 standard.
For more information: http://www.reed-electronics.com/tmworld/article/CA187302.html

STM-n —— synchronous transport module Level N

STP —— (1) shielded twisted pair (2) standard temperature and pressure

STRIFE —— stress and life

subpixel resolution —— Any imaging technique that can yield a measurement with a spatial resolution of less than one pixel.

successive-approximation —— A technique used in ADCs that sequentially compares a series of progressively smaller binary-weighted values with an analog input to produce an output digital word.

SUPI —— Secure User Plane

surge —— A sudden change (usually an increase) in the voltage on a power line. A surge is similar to a spike, but it lasts longer.

susceptibility —— The characteristic of electronic equipment that permits undesirable responses when the equipment is subjected to electromagnetic radiation.

SVF —— serial vector format
For more information: http://www.reed-electronics.com/tmworld/article/CA187586

SWEAT —— standard wafer-level electromigration accelerated test

SWR —— standing wave ratio

sync —— The portion of a video signal that indicates either the end of a field or a line of video information.

T/H —— track and hold

TAB —— tape automated bonding

TACAN —— tactical air navigation

TAP — Test-Access Port

TATR —— Test application time reduction.
For more information: http://www.reed-electronics.com/tmworld/article/CA6338186.html

TC —— (1) temperature coefficient (2) thermocouple

TCE —— thermal coefficient of expansion

Tcl —— Tool Command Language

TCP/IP —— transmission control protocol/Internet protocol

TDM —— time-division multiplexing

TDMA —— time-division multiple access

TDR —— time-domain reflectometer

TD-SCDMA —— time-division synchronous-code-division multiple access

TEM —— (1) transverse electromagnetic mode (2) transmission electron microscope

THD —— total harmonic distortion

throughput rate —— The maximum repetitive rate at which a data-conversion system can operate with a specified accuracy.

TIA —— Telecommunications Industry Association

TIFF —— tagged-image format file

time stamp —— Information added to a unit of data to indicate the time at which it was processed.

TLP —— (1) transaction-layer packet (2) transmission-line pulse

total harmonic distortion (THD) —— See harmonic distortion.

TPS —— Transmission parameter signaling, the signaling of parameters related to a transmission scheme (e.g., to channel, coding, and modulation).
For more information: http://www.reed-electronics.com/tmworld/article/CA604155

TQFP —— thin quad flat pack

TQM —— total quality management

TS —— Transport stream.

TSOP —— thin small-outline package

TTL —— transistor-transistor logic

TUV —— Technische Uberwachungs-Verein (German test lab)

UART —— universal asynchronous receiver-transmitter

UDP —— User Datagram Protocol

UE —— user equipment

UHF —— ultra-high frequency (300 MHz to 3 GHz)

UMB —— Ultra Mobile Broadband

uniform resource locator (URL) —— The name (or string of characters) that uniquely identifies each Web site. For example, www.tmworld.com.

uplink —— a transmission from a mobile unit to a base station

UPS —— uninterruptible power supply

URL —— uniform resource locator

USB —— (1) upper sideband (2) Universal Serial Bus

UTC —— coordinated universal time

UTP —— unshielded twisted pair

UUT —— unit under test

UV —— ultraviolet

UWB —— ultra wideband

V/F —— voltage-to-frequency

VA —— volt-ampere

VAR —— (1) volt-ampere reactive (2) value-added reseller

VB —— Visual Basic

VBW —— video bandwidth

VBX —— Visual Basic extension

VCO —— voltage-controlled oscillator

VCPU —— video capture and processing unit

VCSEL —— Vertical-cavety surface-emitting laser, which, unlike an edge-emitting laser, can be tested at the wafer level.

VDE —— Verband Deutscher Electrotechniker (German national standards organization)

vertical sync —— The portion of a video signal that indicates the end of a field of video information. This sync pulse is used by video equipment to maintain field synchronization with the incoming video signal.

VFC —— voltage-to-frequency converter

VHDL —— VHSIC Hardware Description Language

VHDL-AMS —— VHDL with analog and mixed-signal extentions

VHF —— very high frequency (30 MHz to 300 MHz)

VHSIC —— very high speed integrated circuit

video encoder —— A device that converts RGB video to composite video.

VISA —— Virtual Instrument Software Architecture

VLF —— very low frequency (below 30 kHz)

VLSI —— very-large-scale integration

VM —— virtual machine

VMEbus —— versatile modular E-bus

VNA —— Vector network analyzer

VoD —— video on demand

voice band —— the frequency range the telephone network will carry--300 Hz to 3000 Hz.

VoIP —— Voice over Internet Protocol

voltage-to-frequency converter (VFC) —— A device that converts an analog input voltage into a sequence of digital pulses with a frequency that is proportional to the input voltage.

VOR —— VHF omnidirectional radio

VQFP —— very thin quad flat pack

VSOP —— very small-outline package

VSWR —— voltage standing-wave ratio

VXIbus —— VMEbus extension for instrumentation

Walsh code —— an orthogonal digital code used to spread the spectrum of downlink digital message signals

WAN —— wide area network

W-CDMA —— wideband code-division multiple access

WDM —— wavelength-division multiplexing

WEEE —— Waste Electrical and Electronic Equipment.
For more information: http://www.reed-electronics.com/tmworld/article/CA6311821.html

WiFi —— trade name for wireless technology

WiMAX —— Worldwide Interoperability for Microwave Access