Surface acoustic wave (SAW) and bulk acoustic wave (BAW) duplexers of assessed quality - Part 2: Guidelines for the use

IEC 62604-2:2022 is available as IEC 62604-2:2022 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 62604-2:2022 applies to duplexers which can separate receiving signals from transmitting signals and are key components for two-way radio communications, and which are generally used in mobile phone systems compliant with CDMA systems such as N-CDMA in second generation mobile telecommunication systems (2G), W-CDMA / UMTS (3G) or LTE (4G). These guidelines draw attention to some fundamental questions about the theory of SAW and BAW duplexers and how to use them, which will be considered by the user before he places an order for SAW and BAW duplexers for a new application. Such a procedure will be the user’s insurance against unsatisfactory performance. Because SAW and BAW duplexers have very similar performance for the usage, it is useful and convenient for users that both duplexers are described in one standard. This edition includes the following significant technical changes with respect to the previous edition:
- the term "cross-isolation" has been added to Clause 3;
- multiplexers are described.
NOTE In this document, SAW and BAW duplexers are treated simultaneously because both duplexers are used in the same manner, especially in mobile phone systems and have the same requirements of characteristics, test method and so on.

Duplexeurs à ondes acoustiques de surface (OAS) et à ondes acoustiques de volume (OAV) sous assurance de la qualité - Partie 2 : Lignes directrices d’utilisation

IEC 62604-2:2022 est disponible sous forme de IEC 62604-2:2022 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.L’IEC 62604-2:2022 s’applique aux duplexeurs qui peuvent séparer les signaux en réception des signaux en émission et constituent des composants essentiels pour les radiocommunications bilatérales. Ils sont généralement utilisés dans les systèmes de téléphonie mobile conformes aux systèmes d’accès multiple par répartition en code (AMRC) comme les systèmes N-CDMA des systèmes de télécommunication mobile de seconde génération (2G), les systèmes W-CDMA/UMTS (3G) ou les systèmes LTE (4G). Les présentes lignes directrices attirent l’attention sur certaines des questions fondamentales concernant la théorie des duplexeurs à OAS et à OAV, et leurs modalités d’utilisation, qui sont à prendre en considération par l’utilisateur avant de commander un duplexeur à OAS ou à OAV pour une nouvelle application. Ainsi, l’utilisateur évite d’être confronté à des performances non satisfaisantes. Dans la mesure où les duplexeurs à OAS et à OAV présentent des performances très similaires dans leur utilisation, il est utile et pratique pour les utilisateurs que les deux types soient décrits dans une seule norme. Cette édition inclut les modifications techniques majeures suivantes par rapport à l’édition précédente:
- ajout du terme "isolation de polarisation croisée" à l’Article 3;
- description des multiplexeurs.

General Information

Status
Published
Publication Date
31-Aug-2022
Current Stage
PPUB - Publication issued
Completion Date
01-Sep-2022
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IEC 62604-2
Edition 3.0 2022-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Surface acoustic wave (SAW) and bulk acoustic wave (BAW) duplexers of
assessed quality –
Part 2: Guidelines for the use
Duplexeurs à ondes acoustiques de surface (OAS) et à ondes acoustiques de
volume (OAV) sous assurance de la qualité –
Partie 2: Lignes directrices d’utilisation
IEC 62604-2:2022-09(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 62604-2
Edition 3.0 2022-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Surface acoustic wave (SAW) and bulk acoustic wave (BAW) duplexers of
assessed quality –
Part 2: Guidelines for the use
Duplexeurs à ondes acoustiques de surface (OAS) et à ondes acoustiques de
volume (OAV) sous assurance de la qualité –
Partie 2: Lignes directrices d’utilisation
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.140 ISBN 978-2-8322-4875-1

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
---------------------- Page: 3 ----------------------
– 2 – IEC 62604-2:2022 © IEC 2022
CONTENTS

FOREWORD ........................................................................................................................... 4

INTRODUCTION ..................................................................................................................... 6

1 Scope .............................................................................................................................. 7

2 Normative references ...................................................................................................... 7

3 Terms and definitions ...................................................................................................... 7

3.1 Response characteristics related terms ................................................................... 7

3.2 SAW and BAW duplexers related terms .................................................................. 8

4 Technical considerations ................................................................................................. 8

5 Fundamentals of SAW and BAW duplexers...................................................................... 8

5.1 Basic function ......................................................................................................... 8

5.1.1 General ........................................................................................................... 8

5.1.2 TX filter response (filter response from TX port to antenna port) ...................... 9

5.1.3 RX filter response (filter response from antenna port to RX port) ................... 10

5.1.4 Isolation (isolation from TX port to RX port) ................................................... 10

5.2 Basic structure ...................................................................................................... 11

5.3 Principle of operation ............................................................................................ 11

5.4 Diplexer ................................................................................................................ 14

5.5 Multiplexer ............................................................................................................ 15

6 SAW and BAW duplexer characteristics ......................................................................... 15

6.1 General conditions for SAW and BAW duplexers .................................................. 15

6.2 Typical characteristics of SAW and BAW duplexers .............................................. 18

6.2.1 UMTS duplexer .............................................................................................. 18

6.2.2 US CDMA duplexer ........................................................................................ 18

6.2.3 PCS CDMA duplexer ..................................................................................... 18

6.2.4 LTE Band 1 + Band 3 multiplexer................................................................... 19

7 Application guidelines .................................................................................................... 23

7.1 Power durability .................................................................................................... 23

7.2 Harmonics and inter-modulation distortion ............................................................ 23

7.3 Measurement method for the duplexer .................................................................. 23

7.4 Electrostatic voltage protection ............................................................................. 25

Bibliography .......................................................................................................................... 26

Figure 1 – Basic duplexer configuration .................................................................................. 9

Figure 2 – Basic TX filter response example of SAW and BAW duplexers ............................. 10

Figure 3 – Basic RX filter response example of SAW and BAW duplexers ............................. 10

Figure 4 – Basic isolation characteristics example of SAW and BAW duplexers .................... 11

Figure 5 – The block diagram of a duplexer .......................................................................... 12

Figure 6 – Demanded condition of TX part for duplexers ....................................................... 13

Figure 7 – Phase rotation in TX part ..................................................................................... 13

Figure 8 – Demanded condition of RX part for duplexers ...................................................... 14

Figure 9 – Basic diplexer configuration ................................................................................. 14

Figure 10 – Basic multiplexer configuration ........................................................................... 15

Figure 11 – Typical wide range frequency response of TX filter ............................................ 16

Figure 12 – Typical wide range frequency response of RX filter for upper local system ......... 17

---------------------- Page: 4 ----------------------
IEC 62604-2:2022 © IEC 2022 – 3 –

Figure 13 – Phase shifter by microstrip line on the surface of a ceramic package ................. 17

Figure 14 – Lumped element phase shifter ........................................................................... 17

Figure 15 – Duplexer configuration ....................................................................................... 18

Figure 16 – Frequency characteristics of SAW duplexer for UMTS Band 1 system ................ 20

Figure 17 – Frequency characteristics of a SAW duplexer for US CDMA system ................... 21

Figure 18 – Frequency characteristics of BAW duplexer for PCS CDMA system ................... 22

Figure 19 – Frequency characteristics of SAW Band 1 + Band 3 multiplexer for LTE............. 23

Figure 20 – Four-port-type network analyzer for duplexer measurement ............................... 24

Figure 21 – Four-port-type network analyzer for measurement of a balanced RX port

duplexer................................................................................................................................ 25

Table 1 – Frequency allocation for typical LTE frequency division duplex (FDD) bands .......... 9

---------------------- Page: 5 ----------------------
– 4 – IEC 62604-2:2022 © IEC 2022
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SURFACE ACOUSTIC WAVE (SAW) AND BULK
ACOUSTIC WAVE (BAW) DUPLEXERS
OF ASSESSED QUALITY –
Part 2: Guidelines for the use
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, Technical Reports,

Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their

preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with

may participate in this preparatory work. International, governmental and non-governmental organizations liaising

with the IEC also participate in this preparation. IEC collaborates closely 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

interested IEC National Committees.

3) IEC Publications have the form of recommendations for international use and are accepted by IEC National

Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC

Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any

misinterpretation by any end user.

4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications

transparently to the maximum extent possible in their national and regional publications. Any divergence between

any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.

5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity

assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

services carried out by independent certification bodies.

6) All users should ensure that they have the latest edition of this publication.

7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and

members of its technical committees and IEC National Committees for any personal injury, property damage or

other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and

expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC

Publications.

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.

IEC 62604-2 has been prepared by IEC technical committee 49: Piezoelectric, dielectric and

electrostatic devices and associated materials for frequency control, selection and detection. It

is an International Standard.

This third edition cancels and replaces the second edition published in 2017. This edition

constitutes a technical revision.

This edition includes the following significant technical changes with respect to the previous

edition:
a) the term "cross-isolation" has been added to Clause 3;
b) multiplexers are described.

NOTE In this document, SAW and BAW duplexers are treated simultaneously because both duplexers are used in

the same manner, especially in mobile phone systems and have the same requirements of characteristics, test

method and so on.
---------------------- Page: 6 ----------------------
IEC 62604-2:2022 © IEC 2022 – 5 –
The text of this International Standard is based on the following documents:
Draft Report on voting
49/1361/CDV 49/1376/RVC

Full information on the voting for its approval can be found in the report on voting indicated in

the above table.
The language used for the development of this International Standard is English.

This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in

accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available

at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are

described in greater detail at www.iec.ch/standardsdev/publications.

A list of all parts in the IEC 62604 series, published under the general title Surface acoustic

wave (SAW) and bulk acoustic wave (BAW) duplexers of assessed quality, can be found on the

IEC website.

The committee has decided that the contents of this document will remain unchanged until the

stability date indicated on the IEC website under webstore.iec.ch in the data related to the

specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

IMPORTANT – The "colour inside" logo on the cover page of this document 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.

---------------------- Page: 7 ----------------------
– 6 – IEC 62604-2:2022 © IEC 2022
INTRODUCTION

While in 2G systems mainly dielectric duplexers have been used, the ongoing miniaturization

in 3G and 4G mobile communication systems promoted the development and application of

acoustic wave duplexers due to their small size, light weight and good electrical performance.

While standard surface acoustic wave (SAW) duplexers have been employed for applications

with moderate requirements regarding the steepness of individual filters, applications with

narrow duplex gap (e.g. Bands 2, 3, 8, 25), i.e., the frequency gap between receiving and

transmitting bands, require the application of temperature-compensated (TC) SAW or bulk

acoustic wave (BAW) technology, because of their better temperature characteristics and

resonator Q-factors.

Standard specifications, such as those of IEC, of which these guidelines form a part, and

national specifications or detail specifications issued by manufacturers will define the available

combinations of centre frequency, pass bandwidth and insertion attenuation for each sort of

transmitting and receiving filters and the isolation level between transmitter and receiver ports,

etc. These specifications are compiled to include a wide range of SAW and BAW duplexers with

standardized performances. It cannot be over-emphasized that the user should, wherever

possible, select his duplexers from these specifications, when available, even if it can lead to

making small modifications to his circuit to enable the use of standard duplexers. This applies

particularly to the selection of the nominal frequency band.
---------------------- Page: 8 ----------------------
IEC 62604-2:2022 © IEC 2022 – 7 –
SURFACE ACOUSTIC WAVE (SAW) AND BULK
ACOUSTIC WAVE (BAW) DUPLEXERS
OF ASSESSED QUALITY –
Part 2: Guidelines for the use
1 Scope

This part of IEC 62604 applies to duplexers which can separate receiving signals from

transmitting signals and are key components for two-way radio communications, and which are

generally used in mobile phone systems compliant with CDMA systems such as N-CDMA in

second generation mobile telecommunication systems (2G), W-CDMA / UMTS (3G) or LTE (4G).

These guidelines draw attention to some fundamental questions about the theory of SAW and

BAW duplexers and how to use them, which will be considered by the user before he places an

order for SAW and BAW duplexers for a new application. Such a procedure will be the user’s

insurance against unsatisfactory performance. Because SAW and BAW duplexers have very

similar performance for the usage, it is useful and convenient for users that both duplexers are

described in one standard.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies.

For undated references, the latest edition of the referenced document (including any

amendments) applies.

IEC 60862-1, Surface acoustic wave (SAW) filters of assessed quality – Part 1: Generic

specification

IEC 62575-1, Radio frequency (RF) bulk acoustic wave (BAW) filters of assessed quality –

Part 1: Generic specification
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following

addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1 Response characteristics related terms
3.1.1
guard band

unused part of the radio spectrum between radio bands, for the purpose of preventing

interference
---------------------- Page: 9 ----------------------
– 8 – IEC 62604-2:2022 © IEC 2022
3.1.2
cross-isolation

leakage power ratio from one of the TX ports to one of the RX ports from another nominal

frequency band in a multiplexer
3.2 SAW and BAW duplexers related terms
3.2.1
phase shifter
device which changes the phase of signals, not the frequency of them
Note 1 to entry: This is a basic part of a duplexer.
3.2.2
void

vacancy in the IDT electrode caused by stress migration resulting from diffusing and/or transfer

of metal atoms forming part of the electrode
3.2.3
hillock

projection on the side or upper surface of the electrode caused by stress migration resulting

from diffusing and/or transfer of metal atoms forming part of the electrode
4 Technical considerations

It is of prime interest to a user that the duplexer characteristics should satisfy particular

specifications. The selection of the front-end circuits in user equipment and SAW and BAW

duplexers to meet such specifications should be a matter of agreement between the user and

the manufacturer.

Duplexer characteristics are usually expressed in terms of centre frequency, pass bandwidth and

insertion attenuation for each of transmitting and receiving filter parts in the duplexer and

isolation level between the transmitter and receiver ports. Since the SAW and BAW duplexer is

used in RF front-end of the user equipment, lower insertion attenuation, higher

isolation/rejection level, stronger power durability and smaller/thinner package dimensions are

strictly required.
5 Fundamentals of SAW and BAW duplexers
5.1 Basic function
5.1.1 General

Duplexers are necessary for frequency division duplex (FDD) equipment to receive and transmit

signals simultaneously. Duplexers are 3-port devices which consist of an antenna port, a

transmitter port (TX port) and a receiver port (RX port), as shown in Figure 1. The duplexer has

three basic functions:
• to transfer the transmitting signal from the TX port to the antenna port;
• to transfer the receiving signal from the antenna port to the RX port;

• to prevent transfer of the transmitting signal and noise from the TX port to the RX port.

The transmitting and the receiving frequencies are determined corresponding to each mobile

communication system. For example, Table 1 shows typical allocated frequency bands for LTE.

---------------------- Page: 10 ----------------------
IEC 62604-2:2022 © IEC 2022 – 9 –
Figure 1 – Basic duplexer configuration
Table 1 – Frequency allocation for typical
LTE frequency division duplex (FDD) bands
Downlink Downlink
Uplink frequency Band Uplink frequency
frequency frequency
Band
(MHz) (MHz) (MHz) (MHz)
1 1 920 – 1 980 2 110 – 2 170 16 2 010 – 2 025 2 585 – 2 600
2 1 850 – 1 910 1 930 – 1 990 17 704 – 716 734 – 746
3 1 710 – 1 785 1 805 – 1 880 18 815 – 830 860 – 875
4 1 710 – 1 755 2 110 – 2 155 19 830 – 845 875 – 890
5 824 – 849 869 – 894 20 832 – 862 791 – 821
6 830 – 840 875 – 885 21 1 447,9 – 1 462,9 1 495,5 – 1 510,9
7 2 500 – 2 570 2 620 – 2 690 22 3 410 – 3 490 3 510 – 3 590
8 880 – 915 925 – 960 23 2 000 – 2 020 2 180 – 2 200
9 1 749,9 – 1 784,9 1 844,9 – 1 879,9 24 1 626,5 – 1 660,5 1 525 – 1 559
10 1 710 – 1 770 2 110 – 2 170 25 1 850 – 1 915 1 930 – 1 995
11 1 427,9 – 1 447,9 1 475,9 – 1 495,9 26 814 – 849 859 – 894
12 699 – 716 729 – 746 27 807 – 824 852 – 869
13 777 – 787 746 – 756 28 703 – 748 758 – 803
14 788 – 798 758 – 768 30 2 305 – 2 315 2 350 – 2 360
15 1 900 – 1 920 2 600 – 2 620 31 452,5 – 457,5 462,5 – 467,5

NOTE For a user equipment, uplink frequency means transmitting frequency and downlink frequency means

receiving frequency respectively.
5.1.2 TX filter response (filter response from TX port to antenna port)

Figure 2 shows an example of frequency characteristics of the TX filter. The required frequency

characteristics are low insertion attenuation in the transmitting frequency band (f ), high

insertion attenuation in the receiving frequency band (f ) and good impedance matching.

---------------------- Page: 11 ----------------------
– 10 – IEC 62604-2:2022 © IEC 2022
5.1.3 RX filter response (filter response from antenna port to RX port)

Figure 3 shows an example of frequency characteristics of the RX filter. The required frequency

characteristics are low insertion attenuation in the receiving band (f ) and high insertion

attenuation in the transmitting frequency band (f ).
5.1.4 Isolation (isolation from TX port to RX port)

Figure 4 shows an example of isolation characteristics. One of the important functions for

duplexers is isolation characteristics, which show the frequency dependence of the leakage

power from the TX port to the RX port.
Figure 2 – Basic TX filter response example of SAW and BAW duplexers
Figure 3 – Basic RX filter response example of SAW and BAW duplexers
---------------------- Page: 12 ----------------------
IEC 62604-2:2022 © IEC 2022 – 11 –
Figure 4 – Basic isolation characteristics example of SAW and BAW duplexers
5.2 Basic structure

Duplexers are 3-port devices/modules, which enable to transmit and receive signals

simultaneously through a common antenna. A basic structure of duplexers is shown in Figure 5.

SAW and BAW duplexers consist of a transmitter (TX) part and a receiver (RX) part. These two

parts, which can add a phase shifter, are connected to an antenna port. The phase shifter is

utilized to prevent the interaction between the filters. In Figure 5, Z and Z correspond to the

t r

impedance of the TX and RX part at the antenna port side, whereas Z is the impedance of the

antenna port. The following conditions shall be fulfilled to achieve the duplexer functions.

Z ≅ Z and |Z | >> |Z | in the TX pass band
t o r o
Z ≅ Z and |Z | >> |Z | in the RX pass band
r o t o

DMS (double mode SAW) type filters which are also known as LCRF (longitudinally coupled

1) 2)

resonator filters) , ladder type SAW and BAW filters and other type of SAW filters such as

interdigitated interdigital transducer (lIDT) resonator filters can be adopted as TX and RX

filters. High power durability is required in the TX filters.
5.3 Principle of operation

In the TX pass band, the impedance of the TX part in the antenna port side (Z ) is almost the

), while that of the RX part (Z ) is much higher, which means that at
same as that of antenna (Z
o r
the antenna port, the RX part has large reflection coefficient in this band.
Z ≅ Z and |Z | >> |Z | in the TX pass band
t o r o

On the other hand, in the RX pass band, the impedance of the RX part at the antenna port side

(Z ) is almost the same as that of antenna (Z ), while that of the TX part (Z ) is much higher.

r o t
This also means the TX part has large reflection coefficient in this band.
___________
See IEC 60862-2:2012, 5.3.
See IEC 60862-2:2012, 5.2.
See IEC 60862-2:2012, 5.4.
---------------------- Page: 13 ----------------------
– 12 – IEC 62604-2:2022 © IEC 2022
Z ≅ Z and |Z | >> |Z | in the RX pass band
r o t o
Figure 5 – The block diagram of a duplexer

The transmitting signal applied to the TX port passes through the TX filter and then flows to the

antenna port, not the RX filter. The received signal from the antenna port does not flow to the

TX filter, but to the RX filter. As a result, the TX part and the RX part can share the common

antenna port. In the following explanation, the impedance of the antenna (Z ) is assumed to be

50 Ω. The S curve of the TX part at the antenna port side shall satisfy the demanded conditi

...

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