IEC 62657-2:2013

IEC 62657-2 ®
Edition 1.0 2013-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Industrial communication networks – Wireless communication networks –
Part 2: Coexistence management

Réseaux de communication industriels – Réseaux de communication sans fil –
Partie 2: Gestion de coexistence

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IEC 62657-2 ®
Edition 1.0 2013-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Industrial communication networks – Wireless communication networks –

Part 2: Coexistence management

Réseaux de communication industriels – Réseaux de communication sans fil –

Partie 2: Gestion de coexistence

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XC
ICS 25.040.40; 33.040; 35.110 ISBN 978-2-8322-1048-2

– 2 – 62657-2 © IEC:2013
CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope . 10
2 Normative references . 10
3 Terms, definitions, abbreviated terms and conventions . 10
3.1 Terms and definitions . 10
3.2 Abbreviated terms . 15
3.3 Conventions . 16
4 Coexistence concept in industrial automation . 16
4.1 Overview . 16
4.1.1 General . 16
4.1.2 Manual coexistence management . 18
4.1.3 Automated non-collaborative metrics-based coexistence
management. 18
4.1.4 Automated collaborative metrics-based coexistence management . 18
4.2 Objective . 18
4.3 Necessity to implement a coexistence management . 20
4.4 Interference potential . 22
4.5 Ancillary conditions . 24
4.6 Best practices to achieve coexistence . 24
4.7 Coexistence conceptual model . 27
4.8 Coexistence management and selection of a wireless communication

solution . 29
4.9 Coexistence management system . 31
5 Coexistence management parameters . 31
5.1 General . 31
5.2 Explanation of coexistence parameters . 31
5.2.1 Adjacent channel selectivity . 31
5.2.2 Antenna gain . 31
5.2.3 Antenna radiation pattern . 32
5.2.4 Bandwidth . 32
5.2.5 Bit rate of physical link . 32
5.2.6 Centre frequency . 32
5.2.7 Characteristic of the area of operation . 32
5.2.8 Communication load . 32
5.2.9 Cut-off frequency . 33
5.2.10 Data throughput . 34
5.2.11 Duty cycle . 34
5.2.12 Effective radiated power (EIRP, ERP) . 35
5.2.13 Frequency hopping procedure . 36
5.2.14 Future expansion plan . 36
5.2.15 Geographical dimension of the plant . 36
5.2.16 Infrastructure components . 36
5.2.17 Initiation of data transmission . 36
5.2.18 Length of user data per transmission interval . 36
5.2.19 Limitation from neighbors of the plant . 36
5.2.20 Maximum dwell time . 37

62657-2 © IEC:2013 – 3 –
5.2.21 Maximum number of retransmissions . 37
5.2.22 Maximum transmitter sequence . 37
5.2.23 Mechanisms for adaptivity . 38
5.2.24 Medium access control mechanism. 39
5.2.25 Modulation . 39
5.2.26 Natural environmental conditions . 39
5.2.27 Device characterization parameters . 39
5.2.28 Other frequency users . 39
5.2.29 Packet loss rate (PLR) . 39
5.2.30 Physical links . 40
5.2.31 Positions of wireless devices and distances between them . 40
5.2.32 Power spectral density (PSD) . 40
5.2.33 Purpose of the automation application . 41
5.2.34 Radio channel . 41
5.2.35 Radio propagation conditions . 41
5.2.36 Receiver blocking . 42
5.2.37 Receiver maximum input level . 42
5.2.38 Receiver sensitivity. 42
5.2.39 Regional radio regulations . 42
5.2.40 Relative movement . 42
5.2.41 Reliability required . 42
5.2.42 Response time . 43
5.2.43 Security level required . 43
5.2.44 Spatial coverage of the wireless communication network . 43
5.2.45 Spurious response . 43
5.2.46 Topology . 44
5.2.47 Total radiated power (TRP). 44
5.2.48 Transmission gap . 44
5.2.49 Transmission interval . 45
5.2.50 Transmission time . 45
5.2.51 Transmitter spectral mask . 47
5.2.52 Type of antenna . 48
5.2.53 Update time . 48
5.2.54 Used frequency bands . 49
5.2.55 Wireless devices . 49
5.2.56 Wireless communication networks . 49
5.2.57 Wireless technology or standard . 50
6 Coexistence management information structures . 50
6.1 General . 50
6.2 General plant characteristic . 51
6.3 Application communication requirements . 52
6.3.1 Overview . 52
6.3.2 Requirements influencing the characteristic of wireless solutions . 52
6.3.3 Performance requirements . 53
6.4 Characteristic of wireless system type and wireless device type . 53
6.4.1 Overview . 53
6.4.2 Characteristic of wireless system type . 54
6.4.3 Characteristic of wireless devices type . 55
6.5 Characteristic of wireless communication solution . 57

– 4 – 62657-2 © IEC:2013
6.5.1 Overview . 57
6.5.2 Characteristic of a wireless network solution . 58
6.5.3 Characteristic of wireless devices solution . 58
7 Coexistence management process . 59
7.1 General . 59
7.1.1 Overview . 59
7.1.2 Documentation . 60
7.1.3 Suitable documentation method . 62
7.1.4 Application of tools . 63
7.2 Establishment of a coexistence management system . 63
7.2.1 Nomination of a coexistence manager . 63
7.2.2 Responsibility of a coexistence manager . 64
7.2.3 Support by radio experts. 64
7.2.4 Training . 64
7.3 Maintaining coexistence management system . 65
7.4 Phases of a coexistence management process . 65
7.4.1 Investigation phase . 65
7.4.2 Planning phase . 68
7.4.3 Implementation phase . 70
7.4.4 Operation phase . 71
8 Coexistence parameter templates. 73
Bibliography . 77

Figure 1 – Area of consideration . 20
Figure 2 – Examples of wireless equipment in industrial environments . 21
Figure 3 – Progression of expense to achieve coexistence corresponding to the
application classes . 24
Figure 4 – Separation of wireless communication systems according to frequency and
time . 25
Figure 5 – Coexistence conceptual model . 28
Figure 6 – Flow chart of the coexistence conceptual model . 29
Figure 7 – Selection of a wireless communication system in the coexistence
management process . 30
Figure 8 – Communication load in case of two wireless devices . 33
Figure 9 – Communication load in the case of several wireless devices . 33
Figure 10 – Cut-off frequencies derived from maximum power level . 34
Figure 11 – Duty cycle . 35
Figure 12 – Maximum dwell time . 37
Figure 13 – Maximum transmitter sequence . 38
Figure 14 – Distance of the radio components . 40
Figure 15 – Power spectral density of an IEEE 802.15.4 system . 41
Figure 16 – Minimum transmission gap . 44
Figure 17 – Communication cycle, application event interval and machine cycle . 45
Figure 18 – Example of the density functions of transmission time . 46
Figure 19 – Example of the distribution functions of transmission time . 47
Figure 20 – Transmitter spectral mask of an IEEE 802.15.4 system . 48

62657-2 © IEC:2013 – 5 –
Figure 21 – Example of distribution functions of the update time . 49
Figure 22 – Principle for use of coexistence parameters . 50
Figure 23 – Parameters to describe the general plant characteristic . 51
Figure 24 – Parameters to describe application communication requirements . 52
Figure 25 – Parameters to describe wireless network type and device type . 54
Figure 26 – Power spectral density and transmitter spectral mask of a DECT system . 56
Figure 27 – Medium utilization in time and frequency of a DECT system . 56
Figure 28 – Parameters to describe a wireless communication solution . 58
Figure 29 – Relations of the documents in a coexistence management system
specification . 62
Figure 30 – Planning of a wireless communication system in the coexistence
management process . 69
Figure 31 – Implementation and operation of a wireless communication system in the
coexistence management process . 72

Table 1 – Classification of application communication requirements . 19
Table 2 – Application profile dependent observation time values . 35
Table 3 – List of parameters used to describe the general plant characteristic . 51
Table 4 – List of parameters used to describe the requirements influencing the
characteristic of wireless solutions . 53
Table 5 – List of parameters used to describe performance requirements . 53
Table 6 – List of parameters used to describe the wireless system type . 55
Table 7 – List of parameters used to describe the transmitter of a wireless device type . 57
Table 8 – List of parameters used to describe the receiver of a wireless device type . 57
Table 9 – List of parameters used to describe a wireless network solution . 58
Table 10 – List of parameters used to describe the transmitter of a wireless device
solution . 59
Table 11 – List of parameters used to describe the receiver of a wireless device
solution . 59
Table 12 – Template used to describe the general plant characteristic . 73
Table 13 – Template used to describe the application communication requirements . 74
Table 14 – Template used to describe the wireless system type . 74
Table 15 – Template used to describe a wireless device type . 75
Table 16 – Template used to describe the wireless network solution . 75
Table 17 – Template used to describe a wireless device solution . 76

– 6 – 62657-2 © IEC:2013
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL COMMUNICATION NETWORKS –
WIRELESS COMMUNICATION NETWORKS –

Part 2: Coexistence management

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
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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 62657-2 has been prepared by subcommittee 65C: Industrial
networks, of IEC technical committee 65: Industrial-process measurement, control and
automation.
The text of this standard is based on the following documents:
FDIS Report on voting
65C/736/FDIS 65C/740/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 first edition cancels and replaces IEC/TS 62657-2, published in 2011.

62657-2 © IEC:2013 – 7 –
The main changes with respect to the TS are:
a) updated the normative references, terms, definitions, symbols, abbreviations;
b) corrected spelling;
c) changed figures to make them consistent with the text and vice versa;
d) added and modified text to make the text more readable.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of the IEC 62657 series, under the general title Industrial communication
networks – Wireless communication networks, can be found on the IEC website.
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.
– 8 – 62657-2 © IEC:2013
INTRODUCTION
The market is in need of network solutions, each with different performance characteristics
and functional capabilities, matching diverse application requirements. Industrial automation
applications cover different industrial application domains like:
– process automation, covering for example the following industry branches
• oil & gas, refining,
• chemical,
• pharmaceutical,
• mining,
• pulp & paper,
• water & wastewater,
• steel
– electric power like
• power generation (for example wind turbine),
• power distribution (grid),
– factory automation, covering for example the following industry branches
• food & beverage,
• automotive,
• machinery,
• semiconductor.
Industrial automation applications require behaviors of wireless communication networks that
are different from those that are used for example in telecommunications or for commercial
like a remote control or toy. These industrial automation requirements are identified and
provided in IEC/TS 62657-1.
In industrial automation, many different wireless communication networks may operate in the ®
1 2
same premises. Examples of these networks are IEC 62591 [6] (WirelessHART ),
IEC 62601 [7] (WIA-PA) and IEC/PAS 62734 [9] (ISA100.11a); all these networks use
IEEE 802.15.4 [18] for the process automation applications. Other examples of wireless
networks are specified in IEC 61784-1 [3] and IEC 61784-2 [4] CPs that use IEEE 802.11 [14]
and IEEE 802.15.1 [16] for factory automation applications. Different to wired fieldbuses, the
wireless communication interfaces can interfere with others on the same premises or
environment, disturbing each other. Therefore, without a predictable assuredness of
coexistence, it could be problematic to have multiple wireless communication networks in the
same facility or environment, especially because the time-criticality, the safety and the
security of the operation may not be ensured in such an environment.
This part of the IEC 62657 addresses the coexistence management for a predictable
assuredness of coexistence.
______________
Figures in square brackets refer to the Bibliography.
WirelessHART is the registered trade name of the HART Communication Foundation. This information is given
for the convenience of users of this document and does not constitute an endorsement by IEC of the product
named. Equivalent products may be used if they can be shown to lead to the same results.

62657-2 © IEC:2013 – 9 –
The IEC 62657 series has two parts:
• Part 1: Wireless communication requirements and spectrum considerations
• Part 2: Coexistence management
IEC/TS 62657-1 [8] provides general requirements of industrial automation and spectrum
considerations that are the basis for industrial communication solutions. This second part of
IEC 62657 specifies the coexistence management with a predictable assuredness of
coexistence. It is intended to facilitate harmonization of future adjustments to international,
national, and local regulations.
This Part 2 of IEC 62657 provides the coexistence management concept and process. Based
on the coexistence management process, a predictable assuredness of coexistence can be
achieved for a given spectrum with certain application requirements.
This Part 2 of IEC 62657 provides guidance to the users of wireless communication networks
on selection and proper use of wireless communication networks. To provide suitable wireless
devices to the market, it also serves vendors in describing the behaviors of wireless devices
to build wireless communication networks matching the application requirements.
This Part 2 of IEC 62657 is based on analyses of a number of International Standards, which
focus on specific technologies. The intention of this standard is not to invent new parameters
but to use already defined ones and to be technology independent.

– 10 – 62657-2 © IEC:2013
INDUSTRIAL COMMUNICATION NETWORKS –
WIRELESS COMMUNICATION NETWORKS –

Part 2: Coexistence management

1 Scope
This Part 2 of IEC 62657
• specifies the fundamental assumptions, concepts, parameters, and procedure for wireless
communication coexistence;
• specifies coexistence parameters and how they are used in an application requiring
wireless coexistence;
• provides guidelines, requirements, and best practices for wireless communication's
availability and performance in an industrial automation plant; it covers the life cycle of
wireless communication coexistence;
• helps the work of all persons involved with the relevant responsibilities to cope with the
critical aspects at each phase of life cycle of the wireless communication coexistence
management in an industrial automation plant. Life cycle aspects include: planning,
design, installation implementation, operation, maintenance, administration and training;
• provides a common point of reference for wireless communication coexistence for
industrial automation sites as a homogeneous guideline to help the users assess and
gauge their plant efforts;
• deals with the operational aspects of wireless communication coexistence regarding both
the static human/tool-organization and the dynamic network self-organization.
This Part 2 of IEC 62657 will provide a major contribution to national and regional regulations.
It does not exempt devices to conform to all requirements of national and regional regulations.
EXAMPLE 1 This Part 2 of IEC 62657 could be listed as a harmonized standard in the Official Journal of the
European Union (OJEU) to address the requirements of the European R&TTE directive, Article 3.2 [20], in addition
to other applicable harmonized standards.
EXAMPLE 2 This Part 2 of IEC 62657 could be listed in the Korean Enforcement Decree of the Radio Regulation
Law, Article 18 [21].
2 Normative references
None
3 Terms, definitions, abbreviated terms and conventions
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1.1
adjacent channel interference
interference that occurs when two or more wireless applications use adjacent frequency
channels
62657-2 © IEC:2013 – 11 –
3.1.2
adjacent channel selectivity
ability of a radio receiver to respond to the desired signal and to reject signals in adjacent
frequency channels
3.1.3
antenna
structure or device used to collect or radiate electromagnetic waves
3.1.4
antenna gain
ratio of the power required at the input of a reference antenna to the power supplied to the
input of the given antenna to produce, in a given direction, the same field strength at the
same distance
[SOURCE: Federal Standard 1037C:1996, modified] [19]
3.1.5
antenna radiation pattern
variation of the field intensity of an antenna as an angular function with respect to the axis
3.1.6
automation application
application of measurement and automatic control in the industrial automation domains
3.1.7
automation application data length
number of octets that are exchanged at the communication interface
3.1.8
bandwidth
difference between upper cut-off frequency and lower cut-off frequency
3.1.9
centre frequency
geometric mean of lower cut-off frequency and upper cut-off frequency of a radio channel
3.1.10
channel occupation
time in which the medium is busy
Note 1 to entry: Beyond the pure transfer of user data, this time includes all time slices necessary to process the
transmission protocol, for example to transfer an acknowledgement.
3.1.11
co-channel
emissions or transmissions in the same frequency channel
[SOURCE: IEC 60050-713:1998, 713-06-23, modified] [1]
3.1.12
coexistence
wireless communication coexistence
state in which all wireless communication solutions of a plant using shared medium fulfill all
their application communication requirements
Note 1 to entry: This is consistent with the definition of coexistence in IEEE 802.15.2-2003 [17].

– 12 – 62657-2 © IEC:2013
3.1.13
coexistence assessment
undertaking of an investigation in order to arrive at a judgment, based on evidence of the
suitability of a set of products and their installation to achieve coexistence
[SOURCE: derived from IEC 62278:2002, 3.2] [5]
3.1.14
coexistence management
process to establish and to maintain coexistence that includes technical and organizational
measures
3.1.15
coexistence planning
process that describes the allocation of wireless communication resources (time, frequencies,
coding, space) to each wireless communication system in order to achieve coexistence
3.1.16
communication interface
exposed interface between an automation application and the wireless component
Note 1 to entry: There is no consistently defined interface for measurement and automation. The interface of the
device might be a serial or a parallel hardware interface, a fieldbus interface, a software interface, or serial,
parallel, discrete, and analog interface.
3.1.17
communication load
requirement of the automation application to transfer a certain amount of user data within a
certain period of time
3.1.18
duty cycle
ratio of the transmitter sequence referenced to a given observation time for the used radio
channel
3.1.19
dwell time
period spent at a particular frequency during any single hop of a frequency hopping system
3.1.20
effective radiated power
ERP
power supplied to the antenna multiplied by antenna gain
3.1.21
frequency band
range in the frequency spectrum that is assigned by regulatory organizations for use for
specific applications
3.1.22
frequency channel
part of a frequency band that is used under a specification (standard or device specification)
by a wireless communication system
Note 1 to entry: The coordinated use of different frequency channels is one of the measures to achieve
coexistence.
62657-2 © IEC:2013 – 13 –
3.1.23
immunity
ability of an item to continue operating properly in the event of an interference, up to a certain
level of interference, and to be resilient above this level
Note 1 to entry: Immunity of an item is achieved by adding to the robustness of the item the ability to be resilient
to interference.
3.1.24
intermodulation sensitivity
levels of out-of-band interfering signals that, when mixed in the receiver front-end, produce an
in-band third order non-linearity product
3.1.25
jitter
time variation of an expected occurrence
Note 1 to entry: Examples are variation of transmission time and update time.
3.1.26
lower cut-off frequency
frequency furthest below the frequency of maximum power where the power spectral density
drops below a certain level
3.1.27
mechanisms for adaptivity
measures to modify one or more of the systems operational parameters in order to improve
the systems robustness against interferences and to minimize the medium utilization
3.1.28
metrics
set of quantitative indicators corresponding to selected properties of a communication device,
equipment, or wireless communication system
3.1.29
plant
the facility under consideration, including its physical area of operation, personnel, equipment
and all other contents
3.1.30
power spectral density
signal power per defined bandwidth
3.1.31
radio channel
span of the frequency spectrum which is characterized by lower cut-off frequency and upper
cut-off frequency or by centre frequency and bandwidth
3.1.32
(radio) resource
means used by multiple wireless communication solutions for the purpose of radio signal
transmission
3.1.33
radio robustness
attribute of wireless communication to fulfill the designated function despite the presence of
other active wireless communication applications interfering in the sphere of influence
Note 1 to entry: This term has the same meaning as the definition of the term coexistence in IEEE 802.15.2-2003,
3.1.2 [17].
– 14 – 62657-2 © IEC:2013
3.1.34
receiver blocking
effect of a strong out-of-band interfering signal on the receiver’s ability to detect a low-level
wanted signal
3.1.35
receiver maximum input level
maximum signal power that the system can tolerate without distortion of the signal
3.1.36
receiver sensitivity
minimal signal power to receive data with a defined bit error rate
3.1.37
robustness
ability of an item to continue operating properly in the event of an interference, up to a certain
level of the interference
Note 1 to entry: The robustness of an item may be increased with measures that modify one or more of its
operational parameters.
3.1.38
shared medium
resource of frequency band in particular area shared by several wireless applications
Note 1 to entry: In the industrial, scientific and medical (ISM)-bands many wireless applications are used. Due to
this joint use, the term shared medium is used in this part of IEC 62657. The frequency bands are used by diverse
ISM and wireless applications.
3.1.39
spurious response
receiver output due to unwanted signals
Note 1 to entry: That means having frequencies other than those of the tuned frequency channel.
3.1.40
total radiated power
spatial power density integrated across the surface of the sphere
3.1.41
transmission gap
gap between two successive channel usages by a transmitter
3.1.42
transmission interval
time difference between two consecutive transfers of user data from the automation
application via the communication interface to the communication module
3.1.43
transmission sequence duration
time that a transmitter uses the spectrum for the specific sequence in order to transfer data
3.1.44
transmitter spectral mask
maximum limit of power spectral density over
...