CISPR 16-4-2:2011/AMD2:2018

Amendment 2 - Specification for radio disturbance and immunity measuring apparatus and methods - Part 4-2: Uncertainties, statistics and limit modelling - Measurement instrumentation uncertainty

Amendement 2 - Spécifications des méthodes et des appareils de mesure des perturbations radioélectriques et de l'immunité aux perturbations radioélectriques - Partie 4-2: Incertitudes, statistiques et modélisation des limites - Incertitudes de mesure de l'instrumentation

General Information

• Status: Published
• Publication Date: 14-Aug-2018
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 33.100.10 - Emission
• ICS: 33.100.20 - Immunity
• Technical Committee: A - Radio-interference measurements and statistical methods
• Current Stage: PPUB - Publication issued
• Completion Date: 15-Aug-2018

Standards Content (Sample)

CISPR 16-4-2
Edition 2.0 2018-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
INTERNATIONAL SPECIAL COMMITTEE ON RADIO INTERFERENCE
COMITÉ INTERNATIONAL SPÉCIAL DES PERTURBATIONS RADIOÉLECTRIQUES
BASIC EMC PUBLICATION
PUBLICATION FONDAMENTALE EN CEM
AMENDMENT 2
AMENDEMENT 2
Specification for radio disturbance and immunity measuring apparatus
and methods –
Part 4-2: Uncertainties, statistics and limit modelling – Measurement
instrumentation uncertainty
Spécifications des méthodes et des appareils de mesure des perturbations
radioélectriques et de l'immunité aux perturbations radioélectriques –

Partie 4-2: Incertitudes, statistiques et modélisation des limites – Incertitudes

de mesure de l’instrumentation
CISPR 16-4-2:2011-06/AMD2:2018-08(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
CISPR 16-4-2
Edition 2.0 2018-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
INTERNATIONAL SPECIAL COMMITTEE ON RADIO INTERFERENCE
COMITÉ INTERNATIONAL SPÉCIAL DES PERTURBATIONS RADIOÉLECTRIQUES
BASIC EMC PUBLICATION
PUBLICATION FONDAMENTALE EN CEM
AMENDMENT 2
AMENDEMENT 2
Specification for radio disturbance and immunity measuring apparatus
and methods –
Part 4-2: Uncertainties, statistics and limit modelling – Measurement
instrumentation uncertainty
Spécifications des méthodes et des appareils de mesure des perturbations
radioélectriques et de l'immunité aux perturbations radioélectriques –

Partie 4-2: Incertitudes, statistiques et modélisation des limites – Incertitudes

de mesure de l’instrumentation
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.100.10; 33.100.20 ISBN 978-2-8322-5920-7

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – CISPR 16-4-2:2011/AMD2:2018
© IEC 2018
FOREWORD
This amendment has been prepared by subcommittee CISPR subcommittee A: Radio-

interference measurements and statistical methods, of IEC CISPR committee: International

special committee on radio interference.
The text of this amendment is based on the following documents:
FDIS Report on voting
CISPR/A/1257/FDIS CISPR/A/1259/RVD

Full information on the voting for the approval of this amendment can be found in the report

on voting indicated in the above table.

The committee has decided that the contents of this amendment and the base publication will

remain unchanged until the stability date indicated on the IEC website under

"http://webstore.iec.ch" in the data related to the specific publication. At this date, the

publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
The contents of the corrigendum of January 2019 have been included in this copy.
_____________
2 Normative references
Replace the dated reference CISPR 16-2-3:2010, by the following new reference:

CISPR 16-2-3:2016, Specification for radio disturbance and immunity measuring apparatus

and methods – Part 2-3: Methods of measurement of disturbances and immunity – Radiated

disturbance measurements
3.1 Terms and definitions

Add, after the existing term and definition 3.1.1, the following new term and definition:

3.1.2
small EUT

equipment, either positioned on a table top or standing on the floor that, including its cables,

fits in a cylindrical test volume of 1,5 m in diameter and 1,5 m in height measured from the

floor
3.3 Abbreviations

Add, to the existing list modified by Amendment 1, the following new abbreviations:

---------------------- Page: 4 ----------------------
CISPR 16-4-2:2011/AMD2:2018 – 3 –
© IEC 2018
AN artificial network
Δ-AN artificial Δ-network (‘Δ’ is pronounced ‘delta’)
LLAS large loop antenna system
LV low voltage
V-AMN artificial mains V-network
Table 1 – Values of U
cispr

Replace the first three lines of this table, modified by Amendment 1, by the following new

lines:

Conducted disturbance at AC mains and other power ports using a V-AMN (9 kHz to 150 kHz) 3,8 dB B.1

(150 kHz to 30 MHz) 3,4 dB B.2

Conducted disturbance at AC mains ports using a voltage probe (9 kHz to 30 MHz) 2,9 dB B.3

Add, after the measurement method “Conducted disturbance at telecommunication port using

CP”, the following new line:

Conducted disturbance at telecommunication port using CP and CVP (150 kHz to 30 MHz) 4,0 dB B.5

Add before “Radiated disturbance (electric field strength at an OATS or in a SAC)” the

following new line:

Radiated disturbance (disturbance current in a LLAS) (9 kHz to 30 MHz) 3,3 dB F.1

Add, after the existing NOTE 2, the following new notes:

NOTE 3 The value of U for conducted disturbances at telecommunication ports using CP and CVP is based on

cispr

the expanded uncertainty in Table B.5 with consideration of additional uncertainties attributed to the CP transfer

admittance Y and mismatch uncertainty CP-receiver δM; see comment B18).

NOTE 4 The values of U for the OATS, SAC and FAR are based on a small EUT – an EUT fitting in a

cispr

cylindrical test volume of 1,5 m in diameter and 1,5 m in height – for a 3 m measurement distance (per 3.1.2).

5.1 Conducted disturbance measurements at a mains port using an AMN
Replace, in the title, the phrase "an AMN" by the phrase "a V-AMN".
5.1.1 Measurand for measurements using an AMN
Replace, in the title, the phrase "an AMN" by the phrase "a V-AMN".
---------------------- Page: 5 ----------------------
– 4 – CISPR 16-4-2:2011/AMD2:2018
© IEC 2018
5.1.2 Symbols of input quantities specific to measurements using an AMN
Replace in the title the phrase "an AMN" by the phrase "a V-AMN".
Replace the line starting with δD by the following new line:
mains

δD Correction for the error caused by AC mains and other power supply disturbances,

mains
in dB

5.1.3 Input quantities to be considered for conducted disturbance measurements at a

mains port using an AMN
Replace, in the title, the phrase "an AMN" by the phrase "a V-AMN".
Replace the eighth dashed item by the following new text:

– Effect of disturbances originating from the laboratory AC mains or other power supply

Add, after the existing Subclause 5.6.3 added by Amendment 1, the following new Subclause

5.7:
5.7 Conducted disturbance measurements at AC mains and other power ports using a
Δ-AN
5.7.1 Measurand for measurements using a Δ-AN

V Asymmetric voltage in dB(μV), measured at the EUT port of the Δ-AN relative to the

reference ground plane, and also symmetric voltage between two terminals at the
EUT port of the Δ-AN not including reference ground; optionally also the
unsymmetric voltage in dB(μV), measured at the EUT port of the Δ-AN relative to
the reference ground plane, if the Δ-AN is furnished with a respective port for
connection of the measuring receiver
5.7.2 Symbols of input quantities specific to measurements using a Δ-AN
F Voltage division factor (asymmetric resp. symmetric) of the Δ-AN, in dB

δF Correction for voltage division factor (VDF) frequency interpolation error, in dB

AN f

δD Correction for the error caused by AC mains and other power supply disturbances,

mains
in dB
δV Correction for the effect of the environment, in dB
env
δZ Correction for imperfect asymmetric or symmetric Δ-AN impedance, in dB
5.7.3 Input quantities to be considered for conducted disturbance measurements
at AC mains and other power ports using a Δ-AN
– Receiver reading
– Attenuation of the connection between AN and receiver
– AN voltage division factor (asymmetric and symmetric)
– AN VDF frequency interpolation
– Receiver related input quantities:
• Receiver sine-wave voltage accuracy
• Receiver pulse amplitude response
---------------------- Page: 6 ----------------------
CISPR 16-4-2:2011/AMD2:2018 – 5 –
© IEC 2018
• Receiver pulse response variation with repetition frequency
• Receiver noise floor
– Mismatch effects between the AN's receiver port and receiver
– AN impedance

– Effect of disturbances originating from the laboratory AC mains or other power supply

– Effect of environment
Add, after the existing Clause 8, the following new Clause 9:
9 Radiated disturbance measurements in the frequency range 9 kHz to 30 MHz

9.1 Magnetic field disturbance measurements using the LLAS in the frequency range

9 kHz to 30 MHz (see also Clause F.1)
9.1.1 Measurand for LLAS measurements
I Current in dB(µA), measured in each of the three loops of the LLAS
9.1.2 Symbols of input quantities specific for LLAS measurements
Correction for validation factor deviation, in dB
Correction for validation factor frequency interpolation, in dB
9.1.3 Input quantities to be considered for LLAS measurements
– Receiver reading
– Attenuation of connecting cable between LLAS and receiver
– Validation factor deviation
– Validation factor frequency interpolation
– Receiver related input quantities:
• Receiver sine-wave voltage accuracy
• Receiver pulse amplitude response
• Receiver pulse response variation with repetition frequency
• Receiver noise floor
– Mismatch between LLAS and receiver

9.2 Magnetic field disturbance measurement in the frequency range 9 kHz to 30 MHz

using a loop antenna at various distances from the EUT
(Void)
Annex A – Basis for U values in Table 1, general information and rationale
cispr
for input quantities common to all measurement methods
A.2 Rationale for the estimates of input quantities common to all disturbance
measurements (“A” comments)

Replace, in the existing item A2) modified by Amendment 1, the abbreviation "AMN" by the

abbreviation "V-AMN".
---------------------- Page: 7 ----------------------
– 6 – CISPR 16-4-2:2011/AMD2:2018
© IEC 2018
Add in the first paragraph of A2), after “AMN, AAN, CDNE, CP, CVP, VP” added by
Amendment 1, the abbreviation “LLAS”.

Add, in the first sentence of the first paragraph of item A6), the abbreviation "AN" between the

abbreviations "AMN" and "AAN". Add, in the second paragraph, the term "δF " between

AN f
respective terms for "δF " and "δF ".
AMN f VPf

Replace in the first paragraph of A6), the phrase “absorbing clamp factor and antenna factor”,

by the new phrase “absorbing clamp factor, LLAS validation factor and antenna factor”.

Replace, in item A7) a), the abbreviation "AMN" by the abbreviation "AN".

Replace, in item A7) c) Note 12, the abbreviation "AMN" by the abbreviation "AN".

Annex B – Basis for U values in Table 1, uncertainty budgets and rationale
cispr
for conducted disturbance measurements
B.1 Uncertainty budget for conducted disturbance measurements at a mains
port using an artificial mains network (AMN)
Replace the existing title by the following new title:
B.1 Uncertainty budget for conducted disturbance measurements at AC mains
ports using a V-AMN
Replace the existing Equation (B.1) by the following new equation:
V=V++A F +δF +δV +δV+δV+δV+δδM+ Z +δD +δE (B.1)
r c AN ANf sw pa pr nf AN mains
Table B.1 − Conducted disturbance measurements from 9 kHz to 150 kHz using a
50 Ω/50 μH + 5 Ω AMN

Replace, in the existing title, the abbreviation "AMN" by the new abbreviation "V-AMN".

Table B.2 − Conducted disturbance measurements from 150 kHz to 30 MHz using a
50 Ω/50 μH AMN

Replace, in the existing title, the abbreviation "AMN" by the new abbreviation "V-AMN".

B.6 Rationale for the estimates of input quantities specific to conducted
disturbance measurement methods
Replace the existing comment B10) by the following new comment:

B10) An estimate of the CVP voltage division factor F is assumed to be available from a

CVP

calibration report for the cable type to be measured, along with an expanded uncertainty and

a coverage factor. The uncertainty includes the calibration setup.
---------------------- Page: 8 ----------------------
CISPR 16-4-2:2011/AMD2:2018 – 7 –
© IEC 2018

Add, after the phrase “C.1.3 of CISPR 22:2008” in the existing comment B18), the new phrase

“and in C.4.1.6.4 of CISPR 32:2015 [19]”.

Add, after the existing Clause B.8 added by Amendment 1, the following new Clauses B.9 and

B.10:
B.9 Basis for U values in Table 1, uncertainty budgets and rationale for
cispr
conducted disturbance measurements at mains and other ports using a Δ-
The measurand V is calculated using:
V=V++a F +δF +δV +δV +δV+δV+ δZ +δδM+ D +δV (B.7)
r c AN ANf sw pa pr nf AN mains env
Table B.8 − Conducted disturbances measurements from
150 kHz to 30 MHz using a 150 Ω Δ-AN
a X Uncertainty of x c u(x )
Input quantity i i i i
Probability
dB dB
distribution function
A1)
Receiver reading ± 0,1 k = 1 0,10
A2)
Cable attenuation: AN-receiver ± 0,1 k = 2 0,05
B25)
AN voltage division factor ± 0,2 k = 2 0,10
Receiver corrections:
A3)
Sine wave voltage ± 1,0 k = 2 0,50
A4)
Pulse amplitude response ± 1,5 Rectangular 0,87
A4)
δV ± 1,5 Rectangular 0,87
Pulse repetition rate response
A5)
δV ± 0,0 Rectangular 0,00
Noise floor proximity
A6)
± 0,1 Rectangular 0,06
AN VDF frequency interpolation
ANf
A7)
± 0,07 U-shaped 0,05
Mismatch AN-receiver δM
B26)
AN Impedance (CM) tolerances + 5,37/- 3,67 Triangular 1,84
AN-CM
B26)
AN Impedance (DM) tolerances + 5,37/–1,94 Triangular 1,49
AN-DM
B27)
δD ± 0,0 0,00
Effect of mains disturbances
mains
B19)
Effect of the environment
env
Superscripts refer to numbered comments in A.2 and in this annex.
All sensitivity coefficients c are assumed to be equal to 1, see A.2.
Combined standard uncertainty 2,93
Expanded uncertainty (U ) 2 u
5,86
CISPR c
---------------------- Page: 9 ----------------------
– 8 – CISPR 16-4-2:2011/AMD2:2018
© IEC 2018
B.10 Rationale for the estimates of input quantities specific to the measurement
method using a Δ-AN
B25) Estimates of the Δ-AN voltage division factors F (F and F )
AN AN_asymmetric AN_symmetric
are assumed to be available from a calibration report, along with their expanded
uncertainties and coverage factors.
B26) CISPR 16-1-2 defines the CM impedance of the 150 Ω Δ-AN as 150 Ω with a

magnitude tolerance of ±30 Ω and a phase tolerance of ± 40°. Taking the extremes of

all combinations of the constrained AN CM impedance and the unconstrained EUT
impedance the estimate of the correction δZ is zero with a deviation of + 5,37/-
AN-CM

3,67 dB. A triangular probability distribution is assumed because there is only a small

chance of encountering the particular combinations of AN impedance and EUT

impedance needed to produce those extremes. The triangular distribution is assumed

to be symmetric.

The actual uncertainty will be reduced if the actual CM impedance does not reach the

tolerance limits.
CISPR 16-1-2 defines the DM impedance of the 150 Ω Δ-AN as 150 Ω with a

magnitude tolerance of ± 30 Ω and a phase tolerance of ±40°. Taking the extremes of

all combinations of the constrained AN differential mode impedance and the
unconstrained EUT impedance the estimate of the correction δZ is zero with a
AN-DM

deviation of +5,37/–1,94 dB. A triangular probability distribution is assumed because

there is only a small chance of encountering the particular combinations of AN
impedance and EUT impedance needed to produce those extremes. The triangular
distribution is assumed to be symmetric.

The actual uncertainty will be reduced if the actual DM impedance does not reach the

tolerance limits.

B27) For measurements using a Δ-AN, disturbances from the AC mains, other kind of

power supply or from an external load are assumed to be suppressed by the Δ-AN

itself or by additional filters inserted in the power supply line – if necessary.

Annex D – Basis for U values in Table 1 – Radiated disturbance
cispr
measurements from 30 MHz to 1 000 MHz
Table D.1 – Horizontally polarized radiated disturbances from 30 MHz to 200 MHz
using a biconical antenna at a distance of 3 m, 10 m or 30 m
Replace the table title by the following new title:

Table D.1 – Horizontally polarized radiated disturbances from 30 MHz to 200 MHz using

a biconical antenna at an OATS/SAC at a distance of 3 m, 10 m or 30 m
Table D.2 – Vertically polarized radiated disturbances from 30 MHz to 200 MHz
using a biconical antenna at a distance of 3 m, 10 m or 30 m
Replace the table title by the following new title:

Table D.2 – Vertically polarized radiated disturbances from 30 MHz to 200 MHz using

a biconical antenna at an OATS/SAC at a distance of 3 m, 10 m or 30 m

Table D.3 – Horizontally polarized radiated disturbances from 200 MHz to 1 GHz using

an LPDA antenna at a distance of 3 m, 10 m or 30 m
Replace the table title by the following new title:
---------------------- Page: 10 ----------------------
CISPR 16-4-2:2011/AMD2:2018 – 9 –
© IEC 2018

Table D.3 – Horizontally polarized radiated disturbances from 200 MHz to 1 GHz using

an LPDA antenna at an OATS/SAC at a distance of 3 m, 10 m or 30 m

Replace, in the “LPDA antenna corrections” section of the table, the “Phase centre location

D4)
” details as follows:
D4)
Phase centre location at 3 m ± 0,20 Rectangular 0,12
aph
or 10 m ± 0,06 Rectangular 0,03
aph
or 30 m ± 0,02 Rectangular 0,01
aph

Replace the expanded uncertainty details located just below Table D.3 by the following:

5,12dB, at a separation of 3 m (with tilting)
5,21 dB, at a separation of 3 m (without tilting)
U(E)= 2u (E)=
Hence, expanded uncertainty c 
5,20 dB, at a separation of 10 m
5,19 dB, at a separation of 30 m

Table D.4 – Vertically polarized radiated disturbances from 200 MHz to 1 GHz using an

LPDA antenna at a distance of 3 m, 10 m or 30 m
Replace the table title by the following new title:

Table D.4 – Vertically polarized radiated disturbances from 200 MHz to 1 GHz using an

LPDA antenna at an OATS/SAC at a distance of 3 m, 10 m or 30 m

Replace, in the “LPDA antenna corrections” section of the table, the “Phase centre location

D4)
” details as follows:
D4)
Phase centre location at 3 m ± 0,20 Rectangular 0,12
aph
or 10 m ± 0,06 Rectangular 0,03
aph
or 30 m Rectangular 0,01
± 0,02
aph

Replace the expanded uncertainty details located just below Table D.4 by the following:

5,14 dB, at a separation of 3 m (with tilting)
6,21 dB, at a separation of 3 m (without tilting)
U(E)= 2u (E)=
Hence, expanded uncertainty 
5,21 dB, at a separation of 10 m
5,18 dB, at a separation of 30 m
D.3 Rationale for the estimates of input quantities specific to radiated
disturbance measurement methods from 30 MHz to 1 000 MHz

Replace, in comment D4), all of the existing text and notes by the following new text and

notes:

D4) The correction δF for phase centre location is negligible for a biconical antenna. The

aph

variation in phase-centre location with frequency for an LPDA antenna can be corrected

as recommended in CISPR 16-2-3.
---------------------- Page: 11 ----------------------
– 10 – CISPR 16-4-2:2011/AMD2:2018
© IEC 2018
For an LPDA antenna, the correction δF was assumed to be applied e.g. by
aph
equivalent corrections of the AFs for the specified measurement distance (see

CISPR 16-2-3). The remaining reduced uncertainty is given in Tables D.3 and D.4 with a

rectangular probability distribution, having a half-width evaluated by considering the

effect of an error of ± 0,07 m in the separation, and assuming that field strength is

inversely proportional to separation. For example for d = 10 m,
20 lg(1 + 0,07/10) = 0,06 dB.

NOTE 4 If a tuned dipole is the measuring antenna, the correction δF is negligible.

aph

NOTE 5 For hybrid antennas, the correction δF for the systematic effect is more complicated [see

aph
comment D12)].
Replace, in comment D11) 2 paragraph, the existing text “Subclause 7.2.3 of
CISPR 16-2-3:2010”, by the following new text:
Subclause 7.3.4 of CISPR 16-2-3:2016

Replace, in comment D12), all of the existing text, equations and notes by the following new

text, equations, notes and tables:

D12) Hybrid antennas are taken into account in the calculation of Tables D.7, D.8 and D.9.

Hybrid antennas, used for radiated disturbance measurements in the frequency range

30 MHz to 1 000 MHz and consisting of a broadband dipole section and an LPDA

antenna section, typically have the following characteristics (different parameters for

specific designs may be provided by antenna manufacturers):
– a frequency range up to about 100 MHz, where the antenna acts like a biconical
antenna (see Tables D.1, D.2 and D.5);
– a transition frequency range from about 100 MHz up to about 200 MHz (see below
within this comment); and
– a frequency range above about 200 MHz where the antenna acts like an LPDA
δF it is considered that
antenna (see Tables D.3, D.4 and D.6). For the correction
adir

the LPDA part is usually closer to the EUT than above in comment D3), which means

that the correction factors are slightly higher and the uncertainties are slightly larger.

In the frequency range up to 100 MHz, the following is assumed:

– the AF variation relative to F for horizontal polarization at a height of 1 m reaches a

maximum vs. frequency of ± 2 dB around 60 MHz and at a height of 4 m the variation

is around ± 0,5 dB (data specific for individual antenna types need to be supplied by

the antenna manufacturer). Since at horizontal polarization the antenna height for

OATS/SAC measurements in the frequency range below 100 MHz is at its maximum,
the lower AF height deviation has been assumed.
In the transition frequency range, the following may be assumed for uncertainty
considerations:

– the antenna gain (in dBi) and, by association, the pattern directivity (in dB), increase

linearly with the frequency (detailed antenna patterns for the correction δF may be

adir
obtained from the manufacturer);
– as the frequency increases, the active phase centre travels linearly from the
broadband dipole elements to the 200 MHz elements of the LPDA part [a detailed
calculation of the AF correction δF is given below in Equation (D.4)];
aph
– the cross polarization suppression is equal to or above 20 dB; and
– the balun imbalance will normally be as low as that of the broadband dipole
elements.
---------------------- Page: 12 ----------------------
CISPR 16-4-2:2011/AMD2:2018 – 11 –
© IEC 2018

It is assumed that the antenna is provided with free-space AFs. Free-space AFs apply

to the location of the phase centre. Because the phase centre location on the antenna is

frequency dependent, the distance from a fixed EUT is also frequency dependent.

Equation (8) of CISPR 16-2-3:2016, as well as Equation (A.1) of CISPR 16-1-6:2014 [18],

suggests a field-strength correction. For a given frequency, the following correction, ΔE in dB,

is added to the measured electric field strength:
 d 
phase  d+ Δd
 
ΔE= 20 lg = 20lg
 
 
d d
 
 
(D.3)

According to a note in CISPR 16-2-3 this correction can also be done using distance-

dependent AFs. In order to correct for the deviation from the reference distance, e.g. 10 m or

3 m, the AF is assumed to be corrected. A marker is assumed to be provided on the antenna

midpoint, which is used to define the EUT-to-antenna distance d. Then, the actual AF F is

a act
calculated using the following equations:
F = F +δF
aact a aph
(D.4)
 dd+ Δ 
where δ F = 20lg
aph  
 
and
a act
is the actual (corrected) AF in dB(m );
is the free-space AF in dB(m );
is the correction for phase centre variation in dB;
aph
d is the EUT-to-antenna midpoint distance in m;
d is the EUT-to-phase-centre distance in m;
phase
---------------------- Page: 13 ----------------------
– 12 – CISPR 16-4-2:2011/AMD2:2018
© IEC 2018
Δd is the distance between phase centre and antenna midpoint (positive if phase
centre further away from the EUT than antenna midpoint) in m.
For the frequency range 30 MHz to 100 MHz,∆d= c , i.e. a constant (the distance
of the broadband dipo
...