Anechoic
Neither echoing nor reflective.

Anechoic Chamber
"Shielded enclosure which is lined with radio-frequency absorbers to reduce reflections from the internal surfaces." [IEC-801-3]

Antenna
"Transducer which either emits radio-frequency power into space from a signal source or intercepts an arriving electromagnetic field, converting it into an electrical signal." [IEC-801-3]

Apparatus
"all electrical and electronic appliances together with equipment and installations containing electrical and/or electronic components." [EMC Directive]

Balanced lines
"A pair of symmetrically driven conductors with a conversion loss from differential to common mode of less than 20dB." [IEC 801-5]

Balun
"Device for transforming an unbalanced voltage to a balanced voltage or vice versa. [IEV 161-04-34]." [IEC-801-3]

Burst
"Repetitive pulses occurring during a fixed time interval." [IEC 801-4]

CE mark
A label which identifies an apparatus as complying with all applicable directives.

CISPR
International Special Committee on Radio Interference

Competent Body
an organization, appointed by the EU member's government, which has the technical competence to evaluate compliance to a directive. They do not necessarily have test capabilities.

Conducted
An electromagnetic phenomena transmitted from a device, unit of equipment or system via a conductor, usually a signal, power or interconnecting lead.

Continuous Waves (CW)
"Electromagnetic waves, the successive oscillations of which are identical under steady-state conditions, which can be interrupted or modulated to convey information." [IEC-801-3]

Coupling
"Interaction between circuits, transferring energy from one circuit to another." [IEC 801-4]

Coupling Clamp
"Device of defined dimensions and characteristics for common mode coupling of the interference signal to the circuit under test without any galvanic connection to it." [IEC 801-4]

Coupling Network
"Electrical circuit for the purpose of transferring energy from one circuit to another." [IEC 801-4]

Declaration of Conformity (DoC)
a standardized form used to document the administrative details of the apparatus' compliance

Decoupling Network
"Electrical circuit for preventing EFT-signals applied to the EUT from affecting other devices, equipment or systems which are not under test." [IEC 801-4]

Directive
a policy statement by the European Commission which is to be adopted as national law by each European Union member.

Duration
"The absolute value of the interval during which a specified waveform or feature exists or continues. [IEC 469-1" [IEC 801-5]

EFT/B
"Electrical fast transient-burst." [IEC 801-4] ESD

Electrostatic Discharge EUT
"Equipment under test." [IEC-801-2]

Electrical installation
" An assembly of associated electrical equipment to fulfill a specific purpose or purposes and having coordinated characteristics.[IEV 826-01-01]" [IEC 801-5]

Electromagnetic Compatibility (EMC)
"the ability of a device, unit of equipment or system to perform satisfactorily in its electromagnetic environment without introducing intolerable electromagnetic disturbances to anything in that environment." [EMC Directive]

Electromagnetic Disturbance
defined in the EMC directive as, "any electromagnetic phenomenon which made degrade the performance of a device, unit of equipment or system. An electromagnetic disturbance may be electromagnetic noise, an unwanted signal or a change in the propagation medium itself."

Electromagnetic Interference (EMI)
An "electromagnetic disturbance which manifests itself in performance degradation, malfunction, or failure of electrical or electronic equipment." [IEC-801-2]

Electromagnetic Wave (EM)
"Radiant energy produced by the oscillation of an electric charge characterized by oscillation of the electric and magnetic fields." [IEC-801-3]

Emissions
The electromagnetic output of a device, unit of equipment or system.

European Union
A confederation of European States that have laid aside their sovereignty to form a unified economic entity.

Far Field
"Region where the power flux density from an antenna approximately obeys an inverse square law of the distance." [IEC-801-3]

Field Strength
"The term "field strength" is applied only to measurements made in the far field. The measurements may be of either the electric or the magnetic component of the field and may be expressed as V/m, A/m or W/m2; any one of these may be converted into the others." [IEC-801-3]

Frequency Band
"Continuos range of frequencies extending between two limits." [IEC-801-3]

Frequency modulation (FM)
Process by which the frequency of a carrier wave is varied following a specified law.

Fully Anechoic Chamber
"Shielded enclosure whose internal surfaces are totally lined with anechoic material." [IEC-801-3]

IEC
The International Electrotechnical Commission

ISO
The International Organization for Standardization Immunity - "the ability of a device, unit of equipment or system to perform without degradation of quality in the presence of an electromagnetic disturbance. [EMC Directive]

Induction Field
"Predominant electric and/or magnetic field existing at a distance, d(/2(, where ( is the wavelength." [IEC-801-3]

Isotropic
"Having properties of equal value in all directions." [IEC-801-3]

Mains
power lines Modified semi-anechoic chamber -" Semi-anechoic chamber which has additional absorbers installed on the ground plane." [IEC-801-3]

Normalized Standards
standards which have been published in the "Official Journal of the European Communities" (OJ).

Notified Body
an organization, located within the same member state as the Competent Body, that is authorized to conduct testing on apparatus for which Normalized Standards do not exist.

OJ
the "Official Journal of the European Communities"

Open Area Test Site (OATS)
A reflection free test area with attenuation characteristics that closely approximate the theoretical model. Test sites are further defined by specifying the distance between the test unit and the monitoring antenna. Test sites are typically described as 3 meter, 10 meter or 30 meter sites.

Polarization
"Orientation of the electric field vector of a radiated field." [IEC-801-3]

Port
The interface point of an apparatus under test with the electromagnetic test source or measurement system.

Primary Protection
"The means by which the majority of stressful energy is prevented from propagating beyond the designated interface." [IEC 801-5]

Radiated
An electromagnetic phenomena transmitted from a device, unit of equipment or system via the space surrounding the device, unit of equipment or system. A broadcast signal.

Rise time
"The interval of time between the instants at which the instantaneous value of a pulse first reaches a specified lower value and then a specified higher value." [IEC 801-5]

Sag
A transient wave of electrical current, voltage, or power propagating along a line or circuit and characterized by a rapid decrease followed by a slower increase.

Secondary protection
"The means by which let-through energy from primary protection is suppressed. It may be a special device or an inherent characteristic of the EUT." [IEC 801-5]

Semi-anechoic chamber
"Shielded enclosure where all internal surfaces are covered with anechoic material with the exception of the floor, which shall be reflective (ground plane)." [IEC-801-3]

Shielded enclosure
"Screened or solid metal housing designed expressly for the purpose of isolating the internal from the external electromagnetic environment. The purpose is to prevent outside ambient electromagnetic fields from causing performance degradation and to prevent emissions from causing interference to outside activities." [IEC-801-3]

Spurious radiation
"any undesired electromagnetic emission from an electrical device." [IEC-801-3]

Stripline
"Terminated transmission line consisting of two parallel plates between which a wave is propagated in the transverse electromagnetic mode to produce a specified field for testing purposes. [IEV 161-04-31]." [IEC-801-3]

Surge
"A transient wave of electrical current, voltage, or power propagating along a line or circuit and characterized by a rapid increase followed by a slower decrease. [IEC 161-08-11 modified]." [IEC 801-5]

Susceptibility
"The characteristic of electronic equipment that results in undesirable responses when subjected to electromagnetic energy." [IEC-801-2]

Sweep
"Continuos or incremental traverse over a range of frequencies." [IEC-801-3]

System
"Set of interdependent elements constituted to achieve a given objective by performing a specified function." [IEC 801-5]

Transceiver
"Combination of radio transmitting and receiving equipment in a common housing." [IEC-801-3]

Transient
"Non-periodic and relatively short positive or negative (or both) variable (voltage or current) between two steady states." [IEC 801-4]; "Pertaining to or designating a phenomena or a quality which varies between two consecutive steady states during a time interval short compared to the timescale of interest. [IEC-161-02-01]" [IEC 801-5]

UUT
Unit under test.

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