immunisation
The process of immunising signalling and traction power supplies so they don't interfere with each other.
Electrical engineering
651 entries in this trade.
IMS
Initialism of IP Multimedia Subsystem.
IMSI
Acronym of International Mobile Subscriber Identity.
in series
prep phraseElectrical engineering
Of components: connected in a chain, instead of in parallel.
in-band signaling
The sending of control information within the same band or channel used for data such as voice or video.
inband
adjectiveElectrical engineering
Sent via the same path or method used for primary communication between parties or devices.
integration time
Of an electronic system, the period of time in which a noisy signal is averaged so as to improve the signal-to-noise ratio.
Internet service provider
A company that provides Internet access.
interpole
An auxiliary pole of a commutator placed between the main poles to increase its efficiency.
interrupting time
The time between the trip circuit energization and power arc interruption.
IPBX
Initialism of Internet Protocol private branch exchange: A business telephone system designed to deliver voice over a data network and interoperate with the normal Public Switched Telephone Network (PSTN).
IPL
Initialism of international private line.
IPM
Abbreviation of interior permanent magnet.
ISDN
Initialism of integrated services digital network.
jitter
An abrupt and unwanted variation of one or more signal characteristics.
junction box
A box through which the main conductors of a system of electric distribution pass, and where connection is made with branch circuits or to extend circuits.
keyset
An input device whose few keys can be pressed in many combinations, often simultaneously, to enter different commands or characters.
LAPD
Link Access Procedures, D channel; specified in ITU-T Q.920 and ITU-T Q.921. The second layer protocol on the ISDN protocol stack.
layback
The process of recording the final sound onto the master track.
leakage current
The current that flows through the grounding to earth.
LEC
Abbreviation of local exchange carrier.
level-triggered
adjectiveElectrical engineering
Describing a circuit or component whose output is sensitive to changes of the inputs only so long as the clock input's signal is high.
Lichtenberg figure
A branching pattern on the surface of an insulator that has been subject to an electric discharge
line drop
A drop in voltage between two points of a transmission line.
LIR
Initialism of local interconnection region, an alternative to exchanged-based interconnection strategy for Competitive Local Exchange Carriers (CLECs).
live conductor
Any conductor carrying electrical current.
load factor
The mean load over a given time period divided by the peak load occurring during the same time period, providing a measure of how efficiently an electric system's capacity is being used.
local loop
The physical link or circuit that connects from the demarcation point of the customer premises to the edge of the common carrier or telecommunications service provider's network.
locking shift
A state-dependent encoding mechanism used in data communication (such as GSM SMS) and character encoding standards to switch between different character sets or windows.
Lorentz force
The force exerted on a charged particle in an electromagnetic field.
LOS
Initialism of loss of signal.
lossful
adjectiveElectrical engineering
Lossy; involving loss of information.
lossy
adjectiveElectrical engineering
Of a communication channel, subject to loss of signal strength.
LUDs
local usage details; a list of locally called numbers, often provided by telecom companies to the police as part of an investigation.
LVDS
Initialism of low voltage differential signaling.
machine
An answering machine or, by extension, voice mail.
magnetic circuit
A closed path of magnetic flux.
magnetic equator
A line drawn on a map or chart connecting all points at which the magnetic dip (or magnetic inclination) is zero for a specified epoch.
magnetic moment
The torque exerted on a magnet within a magnetic field; a vector, being the product of the strength of the magnet and the distance between its poles.
magneto-optic effect
The property changes (i.e. polarization, spectrum, phase, intensity) in an electromagnetic wave when it propagates through a medium that has been altered by the presence of a quasistatic magnetic field.
magneto-optic Kerr effect
A magneto-optic effect in which light is reflected from a magnetized surface and may change both polarization and reflected intensity.
make-before-break
adjectiveElectrical engineering
Of a switch or other electronic device, that creates a new electrical connection before an older one is broken.
Manchester coding
A line code in which the encoding of each data bit has at least one transition and occupies the same time.
MBR
Initialism of maximum bitrate.
McIntire joint
An electrical connection spliced together by means of a sleeve (double tube of copper for this purpose).
MDC
Initialism of Motorola data communications.
mechanical splice
A junction of two or more optical fibres aligned and held in place by a small self-contained assembly.
meet-me room
A place within a co-location centre where telecommunications companies can physically connect to one another and exchange data without incurring local loop fees.
memory chip
A RAM, ROM, PROM, EPROM or EEPROM microchip that can be plugged into a personal computer to provide temporary or permanent memory.
mercury arc rectifier
A rectifier which converts alternating current to direct current, using a cathode tube with a pool of liquid mercury. Now superseded by solid-state rectifiers.
MICTOR
Acronym of matched impedance connector.
middle mile
The segment of a telecommunications network linking an operator's core network to the local network plant.
MMF
Initialism of multimode fibre; a type of an optical fibre which is designed to carry a variety rays of light.
MMS
Initialism of Multimedia Messaging Service.
MNP
Initialism of mobile number portability.
mobile data
Internet data transfer over a cellular telephone network rather than Wi-Fi.
mobile station
All the user equipment (mobile phone, SIM card etc) and software needed for communication with a GSM network.
mobile virtual network operator
A provider of mobile telecommunications who does not operate any physical network infrastructure, but relies on contracting with physical mobile telecom network infrastructure operators to provide mobility access.
Morse code
A character code represented by dots and dashes (or short and long pulses), originally used to send messages by telegraph, later by flashes of light or by radio.
MSB
Initialism of main switchboard.