SIST EN 62761:2014

Guidelines for the measurement method of nonlinearity for surface acoustic wave (SAW) and bulk acoustic wave (BAW) devices in radio frequency (RF)

EN IEC 62761 gives the measurement method for nonlinear signals generated in the radio frequency (RF) surface acoustic wave (SAW) and bulk acoustic wave (BAW) devices such as filters and duplexers, which are used in telecommunications, measuring equipment, radar systems and consumer products. The IEC 62761 includes basic properties of non-linearity, and guidelines to setup the measurement system and to establish the measurement procedure of nonlinear signals generated in SAW/BAW devices. It is not the aim of this standard to explain theory, nor to attempt to cover all the eventualities which may arise in practical circumstances. This standard draws attention to some of the more fundamental questions, which the user has to consider before he/she places an order for an RF SAW/BAW device for a new application. Such a procedure will be the user's insurance against unsatisfactory performance.

Leitfaden zum Messverfahren für die Nichtlinearität von Oberflächenwellen-(OFW-) und Volumenwellen-(BAW-)Bauelementen für Hochfrequenzanwendungen

Lignes directrices pour la méthode de mesure des non-linéarités pour les dispositifs à ondes acoustiques de surface (OAS) et à ondes acoustiques de volume (OAV) pour fréquences radioélectriques (RF)

IEC 62761:2014-02(en-fr) présente la méthode de mesure pour des signaux non-linéaires générés dans les dispositifs à ondes acoustiques de surface (OAS) et à ondes acoustiques de volume (OAV) pour les fréquences radioélectriques (RF), tels que les filtres et les duplexeurs utilisés dans les télécommunications, les équipements de mesure, les systèmes radar et les produits de grande consommation. Il inclut des propriétés de base de la non-linéarité, et des lignes directrices pour installer le système de mesure et pour établir la procédure de mesure des signaux non-linéaires générés dans des dispositifs à OAS/OAV.

Smernice za metodo merjenja nelinearnosti površinskega zvočnega vala (SAW) in visokofrekvenčnega zvočnega vala (BAW) pri napravah v radiofrekvenčnem območju (IEC 62761:2014)

Standard EN IEC 62761 določa metodo merjenja nelinearnih signalov površinskih zvočnih valov (SAW) in visokofrekvenčnih zvočnih valov (BAW) pri napravah v radiofrekvenčnem območju, kot so filtri in dupleksorji, ki se uporabljajo v telekomunikacijah, merilni opremi, radarskih sistemih in potrošniških proizvodih. Standard IEC 62761 zajema osnovne lastnosti nelinearnosti ter smernice za vzpostavitev merilnega sistema in določitev postopka merjenja nelinearnih signalov, ki jih proizvajajo naprave SAW/BAW. Cilj tega standarda ni pojasniti teorijo, niti poskusiti zajeti vseh morebitnih primerov, do katerih lahko pride v praktičnih okoliščinah. Ta standard opozarja na nekatera bolj temeljna vprašanja, o katerih bi moral razmisliti uporabnik(-ca), preden naroči RF napravo SAW/BAW za novo uporabo. S tem se bo zavaroval pred nezadovoljivo izvedbo.

General Information

• Status: Published
• Publication Date: 12-Aug-2014
• Technical Committee: I11 - Imaginarni 11
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 14-Jul-2014
• Due Date: 18-Sep-2014
• Completion Date: 13-Aug-2014
• Ref Project: EN 62761:2014 - Guidelines for the measurement method of nonlinearity for surface acoustic wave (SAW) and bulk acoustic wave (BAW) devices in radio frequency (RF)

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 62761:2014
01-september-2014
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YLVRNRIUHNYHQþQHJD]YRþQHJDYDOD%$:SULQDSUDYDKYUDGLRIUHNYHQþQHP
REPRþMX,(&
Guidelines for the measurement method of nonlinearity for surface acoustic wave (SAW)
and bulk acoustic wave (BAW) devices in radio frequency (RF)
Lignes directrices pour la méthode de mesure des non-linéarités pour les dispositifs à
ondes acoustiques de surface (OAS) et à ondes acoustiques de volume (OAV) pour
fréquences radioélectriques (RF)
Ta slovenski standard je istoveten z: EN 62761:2014
SIST EN 62761:2014 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 62761:2014

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SIST EN 62761:2014


EUROPEAN STANDARD EN 62761

NORME EUROPÉENNE

EUROPÄISCHE NORM
May 2014
ICS 31.140

English Version
Guidelines for the measurement method of nonlinearity for
surface acoustic wave (SAW) and bulk acoustic wave (BAW)
devices in radio frequency (RF)
(IEC 62761:2014)
Lignes directrices pour la méthode de mesure des non- Leitfaden zum Messverfahren für die Nichtlinearität von
linéarités pour les dispositifs à ondes acoustiques de Oberflächenwellen-(OFW-) und Volumenwellen-
surface (OAS) et à ondes acoustiques de volume (OAV) (BAW-)Bauelementen für Hochfrequenzanwendungen
pour fréquences radioélectriques (RF) (IEC 62761:2014)
(CEI 62761:2014)
This European Standard was approved by CENELEC on 2014-03-26. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.


European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2014 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
 Ref. No. EN 62761:2014 E

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SIST EN 62761:2014
EN 62761:2014 - 2 -
Foreword
The text of document 49/1091/FDIS, future edition 1 of IEC 62761, prepared by IEC/TC 49
"Piezoelectric, dielectric and electrostatic devices and associated materials for frequency control,
selection and detection" was submitted to the IEC-CENELEC parallel vote and approved by
CENELEC as EN 62761:2014.
The following dates are fixed:
– latest date by which the document has to be implemented at (dop) 2014-12-26
national level by publication of an identical national
standard or by endorsement
– latest date by which the national standards conflicting with (dow) 2017-03-26
the document have to be withdrawn

Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such
patent rights.
Endorsement notice
The text of the International Standard IEC 62761:2014 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:
IEC 60862-1:2003 NOTE Harmonized as EN 60862-1:2003 (not modified).
IEC 62047-7:2011 NOTE Harmonized as EN 62047-7:2011 (not modified).
IEC 62575-2:2012 NOTE Harmonized as EN 62575-2:2012 (not modified).

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SIST EN 62761:2014




IEC 62761

®


Edition 1.0 2014-02




INTERNATIONAL



STANDARD




NORME



INTERNATIONALE
colour

inside










Guidelines for the measurement method of nonlinearity for surface acoustic

wave (SAW) and bulk acoustic wave (BAW) devices in radio frequency (RF)




Lignes directrices pour la méthode de mesure des non-linéarités pour les

dispositifs à ondes acoustiques de surface (OAS) et à ondes acoustiques de

volume (OAV) pour fréquences radioélectriques (RF)
















INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE

PRICE CODE
INTERNATIONALE

CODE PRIX T


ICS 31.140 ISBN 978-2-8322-1425-1



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

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SIST EN 62761:2014
– 2 – 62761 © IEC:2014
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
3.1 General terms . 6
3.2 Response related terms . 8
3.3 Nonlinearity related terms . 9
4 Basic properties of nonlinear system . 10
4.1 Behaviours of nonlinear system . 10
4.2 Measurement setup for nonlinearity . 12
4.2.1 Harmonics measurement . 12
4.2.2 IMD Measurement . 14
4.3 Influence of circuit impedance for nonlinearity measurement . 16
4.4 Influence of circuit nonlinearity . 18
5 Nonlinearity measurement . 18
5.1 Measurement equipment . 18
5.1.1 Signal generator and power amplifier . 18
5.1.2 Spectrum analyser . 18
5.1.3 Network analyser (optional) . 19
5.1.4 Accessories . 19
5.2 Measurement Specifications . 19
5.3 Measurement procedure . 21
5.3.1 DUT check . 21
5.3.2 Setup and check . 21
5.3.3 Data acquisition . 21
5.3.4 DUT final check . 22
5.4 Report. 22
Bibliography . 23

Figure 1 – FBAR configuration . 7
Figure 2 – SMR configuration. 8
Figure 3 – Fundamental and harmonics output as a function of input signal power. 12
Figure 4 – Basic setup for the harmonics measurement . 13
Figure 5 – Practical setup for the harmonics measurement . 13
Figure 6 – Setup when the circulator/isolator is used . 14
Figure 7 – Practical setup for the IMD measurement (two-tone test) . 15
Figure 8 – Practical setup for three-tone measurement . 16
Figure 9 – Setup for IMD2 measurement of SAW/BAW antenna duplexers . 16
Figure 10 – Range of deviation resulting from δ in dB . 17
Figure 11 – Ideal IMD2 measurement setup for RF SAW/BAW duplexers . 20
Figure 12 – Setup for the measurement of input signal intensity . 22

Table 1 – Frequencies f and f of input signals and target frequency f . 20
a b t

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62761 © IEC:2014 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

GUIDELINES FOR THE MEASUREMENT METHOD OF NONLINEARITY FOR
SURFACE ACOUSTIC WAVE (SAW) AND BULK ACOUSTIC WAVE (BAW)
DEVICES IN RADIO FREQUENCY (RF)

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
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with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62761 has been prepared by IEC technical committee 49:
Piezoelectric, dielectric and electrostatic devices and associated materials for frequency
control, selection and detection.
The text of this standard is based on the following documents:
FDIS Report on voting
49/1091/FDIS 49/1098/RVD

Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

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SIST EN 62761:2014
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The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site 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.

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.

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SIST EN 62761:2014
62761 © IEC:2014 – 5 –
INTRODUCTION
Radio frequency (RF) surface acoustic wave (SAW) and bulk acoustic wave (BAW) devices
such as filters and duplexers are now widely used in various communication systems. Due to
their small physical size, energy concentration causes generation of nonlinear signals even
when relatively small electric power is applied, and they may interfere with the
communications.
The features of these RF SAW/BAW devices are their small size, light weight, omission of
impedance and/or frequency tuning, high stability and high reliability. Nowadays, RF
SAW/BAW devices with low insertion attenuation are widely used in various applications in
the RF range.
In such applications, suppression of transmission and generation of unnecessary signals is
highly demanded. Since nonlinearity in the RF SAW/BAW devices will generate such signals,
its ultimate suppression is always crucial. In the same time, measurement method of
nonlinear signals should be well established from industrial points of view.
In passive filters like RF SAW/BAW ones, frequency selectivity is realized by impedance
matching/mismatching with peripheral circuitry. Thus impedance of peripheral circuitry shall
be set as specified for reliable and reproducible filter characterization. This is also true for
non-linear characteristics. It should be noted that even-order non-linearity, which is not
common in general passive electronic components, may occur in RF SAW/BAW devices
employing piezoelectric materials for electrical excitation and detection of SAWs/BAWs. This
is because crystallographic asymmetry is necessary for existence of piezoelectricity.
Therefore, measurement methods should be specifically established for non-linear behavior of
RF SAW/BAW devices.
This standard has been compiled in response to a generally expressed desire on the part of
both users and manufacturers for general Information on test condition guidance of RF
SAW/BAW filters, so that the filters may be used to their best advantage. To this end, general
and fundamental characteristics have been explained in this standard.

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SIST EN 62761:2014
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GUIDELINES FOR THE MEASUREMENT METHOD OF NONLINEARITY FOR
SURFACE ACOUSTIC WAVE (SAW) AND BULK ACOUSTIC WAVE (BAW)
DEVICES IN RADIO FREQUENCY (RF)



1 Scope
This International Standard gives the measurement method for nonlinear signals generated in
the radio frequency (RF) surface acoustic wave (SAW) and bulk acoustic wave (BAW) devices
such as filters and duplexers, which are used in telecommunications, measuring equipment,
radar systems and consumer products.
The IEC 62761 includes basic properties of non-linearity, and guidelines to setup the
measurement system and to establish the measurement procedure of nonlinear signals
generated in SAW/BAW devices.
It is not the aim of this standard to explain theory, nor to attempt to cover all the eventualities
which may arise in practical circumstances. This standard draws attention to some of the
more fundamental questions, which the user has to consider before he/she places an order
for an RF SAW/BAW device for a new application. Such a procedure will be the user's
insurance against unsatisfactory performance.
2 Normative references
None
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1 General terms
3.1.1
BAW duplexer
antenna duplexer composed of RF BAW resonators
3.1.2
BAW filter
filter characterised by a bulk acoustic wave which is usually generated by a pair of electrodes
and propagates along a thin film thickness direction
3.1.3
bulk acoustic wave
BAW
acoustic wave, propagating between the top and bottom surface of a piezoelectric structure
and traversing the entire thickness of the piezoelectric bulk
Note 1 to entry: The wave is excited by metal electrodes attached to both sides of the piezoelectric layer.
3.1.4
cut-off frequency
frequency of the pass-band at which the relative attenuation reaches a specified value

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3.1.5
duplexer
device used in the frequency division duplex system, which enables the system to receive and
transmit signal through a common antenna simultaneously
3.1.6
film bulk acoustic resonator
FBAR
thin film BAW resonator consisting of a piezoelectric layer sandwiched between two electrode
layers with stress free top and bottom surface supported mechanically at the edge on a
substrate with cavity structure as shown in Figure 1 or membrane structure as an example
Note 1 to entry: This note applies to the French language only.
Upper electrode



Piezoelectric material
Supporting
h
layer


Lower electrode
Supporting
substrate
IEC  0652/14

Figure 1 – FBAR configuration
3.1.7
Receiver (Rx) band
frequency band used in a receiver part to detect signals from an antenna
3.1.8
Rx filter
filter used in a receiver part to eliminate unnecessary signals
Note 1 to entry: The Rx filter is a basic part of a duplexer.
3.1.9
SAW filter
filter characterised by one or more surface acoustic wave transmission line or resonant
elements, where the surface acoustic wave is usually generated by an interdigital transducer
and propagates along a substrate
3.1.10
solidly mounted resonator
SMR
BAW resonator, supporting the electrode/piezoelectric layer/electrode structure by a
sequence of additional thin films of alternately low and high acoustic impedance Z with
a
quarter wavelength layer, and these layers act as acoustic reflectors and decouple the
resonator acoustically from the substrate as shown in Figure 2 for example
Note 1 to entry: This note applies to the French language only.

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SIST EN 62761:2014
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Upper electrode



Piezoelectric material h

Lower electrode



Lower Z layer
a

Higher Z layer
a


 Supporting
substrate
IEC  0653/14

Figure 2 – SMR configuration
3.1.11
surface acoustic wave
SAW
acoustic wave, propagating along a surface of an elastic substrate, whose amplitude decays
exponentially with substrate depth
[SOURCE: IEC 60862-1:2003, 2.2.1.1]
3.1.12
transmitter (Tx) band
frequency band used in a transmitter part to emit signals from an antenna
3.1.13
Tx filter
filter used in a transmitter part to eliminate unnecessary signals. It is a basic part of a
duplexer
3.2 Response related terms
3.2.1
insertion attenuation
logarithmic ratio of the power delivered directly to the load impedance before insertion of the
duplexer to the power delivered to the load impedance after insertion of the duplexer
3.2.2
pass band
band of frequencies in which the relative attenuation is equal to or less than a specified value
3.2.3
reflectivity
dimensionless measure of the degree of mismatch between two impedances Z and Z , i.e.,
1 2
Z − Z
1 2
, where Z and Z represent respectively the input and source impedance or the
1 2
Z + Z
1 2
output and load impedance
Note 1 to entry: The absolute value of reflectivity is called the reflection coefficient.

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3.2.4
relative attenuation
difference between the attenuation at a given frequency and the attenuation at the reference
frequency
3.2.5
stop band
band of frequencies in which the relative attenuation is equal to or greater than a specified
value
3.2.6
transition band
band of frequencies between the cut-off frequency and the nearest point of the adjacent stop
band
3.3 Nonlinearity related terms
3.3.1
harmonics
non-linear distortion of a device response characterized by the appearance of frequencies at
the output equal to integral multiples of the original signal frequency
3.3.2
hysteresis
memory effect
phenomenon where the output is not determined only from the input and depends also on the
internal state, in other words, the history of the input
3.3.3
intercept point
IP
power level where intensity of the non-linear signal generated by the intermodulation distortion (IMD) is equal to
that of two input signals at the output
Note 1 to entry: This note applies to the French language only.
3.3.4
intermodulation distortion
IMD
non-linear distortion of a device response characterized by the appearance of frequencies at the output equal to
the differences (or sums) of integral multiples of the two or more component frequencies present at the input
Note 1 to entry: This note applies to the French language only.
3.3.5
jammer signal
incoming unnecessary signal
3.3.6
nonlinear distortion
distortion of the signal waveform caused by nonlinearity of the system where the signal
transmits
Note 1 to entry: When the distortion is originated to the frequency dependence of the system signal transfer
function, it is called the linear distortion.
3.3.7
one decibel compression point
input power where gain, the ratio of the output to the input, decreases by 1 dB from the value
when the input is very weak

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3.3.8
saturation
phenomenon where gain, the ratio of the output to the input, decreases and approaches to
zero when the input is large
3.3.9
three tone test
non-linearity measurement applying three sinusoidal signals with different frequencies
simultaneously
3.3.10
triple beat test
same as the three tone test
3.3.11
two tone test
non-linearity measurement applying two sinusoidal signals with different frequencies
simultaneously
4 Basic properties of nonlinear system
4.1 Behaviours of nonlinear system
Let us consider a response y(x) of a circuit or a device when a signal x is applied. When the
hysteresis (memory effect) is negligible or ignored, the Maclaurin expansion of y with respect
to x gives
1 1
2 3
  (1)
y(x) = c x + c x + c x +
1 2 3
2 3
where c is the expansion coefficient. It should be noted that c = 0 for even m, when the
m m
circuit/device satisfies y(− x) = − y(x).
Here we consider a case when two sinusoidal signals with frequencies f and f and
a b
amplitudes a and a are simultaneously applied, namely, x = a cos(2πf t) + a cos(2πf t), and
a b a a b b
a is much greater than a . Then y is approximately given by
a b
2 2
   
c a c a
3 a 3 a
   
y ≈ c a 1+ cos(2πf t) + c a 1+ cos(2πf t)
1 a a 1 b b
   
4c 2c
 1   1 
2 2 3
c a c a c a
2 a 2 a 3 a
   + + cos(4πf t) + cos(6πf t)
a a
4 4 4
c a a c a a
2 a b 2 a b
  (2)
   + cos{2π ( f + f )t}+ cos{2π ( f − f )t}
a b a b
2 2
2 2
c a a c a a
3 a b 3 a b
   + cos{2π (2 f + f )t}+ cos{2π (2 f − f )t}
a b a b
4 4
   +
Equation (2) indicates how nonlinearity influences to the circuit/device output. Namely, the
first two terms indicate change in the transmission coefficients for a and a , and express
a b
saturation due to large signal input (usually c /c is negative). The three terms in the second
3 1
line express generation of harmonics with f = mf (m: integer). The two terms in the third line
a
express generation of new signals with f = f ± f called the second-order intermodulation
a b

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distortion (IMD2). The remaining two terms in the fourth line express those with f = |2f ± f | or
a b
f = |2f ± f | called the third-order intermodulation distortion (IMD3).
b a
Here we consider a wireless receiver tuned for a signal with f = f . Incident signals with f = f /2
t t
and f = f /3 may be detected by the receiver after the harmonics generation, and may interfere
t
the main signal detection. Similarly, when two signals with f and f satisfying either
a b
f = |f ± f |, |2f ± f | or |f ± 2f | are incident to the receiver simultaneously, signals with f = f
t a b a b a b t
generated by IMD2 or IMD3 may also interfere the main signal detection. For transceivers
operating in the frequency division duplex (FDD) mode, transmitting signals with f=f may
a
cause IMD2 and/or IMD3 with an incident signal with f = f , and generated signals with f = f
b t
may also interfere the main signal detection. For transmitters, nonlinearity causes emission of
spurious signals, which may interfere with other wireless communications. These examples
clearly reveal importance to characterise nonlinear behaviour of RF systems and components
as well as the suppression.
For the characterisation of the transmission compression (saturation), we often use the input
signal level where the transmission coefficient decreases by 1 dB, which is called the 1dB
compression point (P ). On the other hand, so called the intercept point is used for the IMD
1dB
characterisation. That is, power P of the IMD2 signal with f = |f ± f | is expressed as
a±b a b
P = P P /OIP2 when signal levels are much lower than the saturation levels. In the
a±b oa ob
expression, P and P are the output power with f and f and OIP2 is called the output
oa ob a b
second-order intercept point. In decibels, the relation is rewritten as
OIP2 = P + P – P (3)
oa ob a±b
In Equation (3), all variables are expressed in dBm.
Similarly, power P of the IMD3 signal with f = |2f ± f | is expressed as
2a ± b a b
2 2
=P P /OIP3 when signal levels are much lower than the saturation levels. In the
P
2a±b oa ob
equation, OIP3 is called the output third-order intercept point. In decibels, the relation is
rewritten as
OIP3 = P + 1/2 × P – 1/2 × P (4)
oa ob 2a ± b
In Equation (4), all variables are expressed in dBm.
It should be noted that the intercept point is also defined by the input signal level P (= P )
ia ib
giving P = OIP2 and P = OIP3. The input second- and third-order intercept points IIP2
a ± b 2a ± b
and IIP3 are related to OIP2 and OIP3 as
IIP2 = OIP2 + IA (5)
and
IIP3 = OIP3 + IA (6)
where IA is the insertion attenuation in dB of the device measured with very weak input signal
level.
Figure 3 shows typical variation of P (n = 1), P (n = 2) and P (n = 3) with P (= P ).
oa a±b 2a±b ia ib
OIPn and IIPn can be estimated graphically from the intersection points between extrapolated
two linear lines. In this case, IIP2 and IIP3 are about 25 dBm and 33 dBm
...