EN 62657-2:2017

SLOVENSKI STANDARD
01-december-2017
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SIST EN 62657-2:2015
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Industrial communication networks - Wireless communication networks - Part 2:
Coexistence management (IEC 62657-2:2017)
Industrielle Kommunikationsnetze - Funk-Kommunikationsnetze - Teil 2: Koexistenz-
Management (IEC 62657-2:2017)
Réseaux de communication industriels - Réseaux de communication sans fil - Partie 2:
Gestion de coexistence (IEC 62657-2:2017)
Ta slovenski standard je istoveten z: EN 62657-2:2017
ICS:
25.040.40 Merjenje in krmiljenje Industrial process
industrijskih postopkov measurement and control
35.110 Omreževanje Networking
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN 62657-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2017
ICS 25.040.40; 33.040; 35.100 Supersedes EN 62657-2:2015
English Version
Industrial communication networks - Wireless communication
networks - Part 2: Coexistence management
(IEC 62657-2:2017)
Réseaux de communication industriels - Réseaux de Industrielle Kommunikationsnetze - Funk-
communication sans fil - Partie 2: Gestion de coexistence Kommunikationsnetze - Teil 2: Koexistenz-Management
(IEC 62657-2:2017) (IEC 62657-2:2017)
This European Standard was approved by CENELEC on 2017-06-15. 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, Serbia, 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
© 2017 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 62657-2:2017 E
European foreword
The text of document 65C/861/FDIS, future edition 2 of IEC 62657-2, prepared by SC 65C “Industrial
networks” of IEC/TC 65 “Industrial-process measurement, control and automation" was submitted to
the IEC-CENELEC parallel vote and approved by CENELEC as EN 62657-2:2017.

The following dates are fixed:
(dop) 2018-03-15
• latest date by which the document has to be
implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2020-06-15
standards conflicting with the
document have to be withdrawn
This document supersedes EN 62657-2:2015.

Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Endorsement notice
The text of the International Standard IEC 62657-2:2017 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 61158 Series NOTE Harmonized as EN 61158 Series.
IEC 61360 Series NOTE Harmonized as EN 61360 Series.
IEC 61784-1 NOTE Harmonized as EN 61784-1.
IEC 61784-2 NOTE Harmonized as EN 61784-2.
IEC 61918 NOTE Harmonized as EN 61918.
IEC 62591 NOTE Harmonized as EN 62591.
IEC 62601 NOTE Harmonized as EN 62601.
IEC 62734 NOTE Harmonized as EN 62734.
IEC 62890 NOTE Harmonized as EN 62890.
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.

NOTE 1 When an International Publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available here:
www.cenelec.eu
Publication Year Title EN/HD Year

IEC 62657-1 2017 Industrial communication networks - EN 62657-1 201X
Wireless communication networks -
Part 1: Wireless communication
requirements and spectrum considerations
IEC 62443 Series Industrial communication networks - EN 62443 Series
Network and system security
At draft stage.
IEC 62657-2 ®
Edition 2.0 2017-05
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
INTERNATIONALE
ICS 25.040.40; 33.040; 35.100 ISBN 978-2-8322-4214-8

– 2 – IEC 62657-2:2017 © IEC 2017

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 . 21
3.3 Conventions . 22
4 Coexistence concept in industrial automation . 22
4.1 Overview. 22
4.2 Objective . 24
4.3 Necessity to implement a coexistence management . 26
4.4 Interference potential . 28
4.5 Ancillary conditions . 29
4.6 Requirements to wireless devices for support of coexistence management . 30
4.7 Concepts . 30
4.7.1 Manual coexistence management . 30
4.7.2 Automated non-collaborative metrics-based coexistence management . 31
4.7.3 Automated collaborative metrics-based coexistence management . 31
4.8 Best practices to achieve coexistence . 32
4.9 Coexistence conceptual model . 34
4.10 Coexistence management and selection of a wireless solution . 36
4.11 Coexistence management system . 38
5 Coexistence management parameters . 38
5.1 General . 38
5.1.1 Definition and usage of parameters . 38
5.1.2 Physical link . 38
5.2 Adjacent channel selectivity . 38
5.3 Antenna gain . 39
5.4 Antenna radiation pattern . 39
5.5 Antenna type . 39
5.6 Availability . 39
5.7 Bandwidth . 40
5.8 Bit rate of physical link . 40
5.9 Centre frequency . 40
5.10 Characteristic of the area of operation . 40
5.11 Communication load . 40
5.12 Cut-off frequency . 42
5.13 Data throughput . 43
5.14 Device type information . 43
5.15 Distance between wireless devices . 43
5.16 Duty cycle . 44
5.17 Dwell time . 46
5.18 Equivalent isotropic radiated power. 47
5.19 Equivalent radiated power . 47
5.20 Frequency band . 47

IEC 62657-2:2017 © IEC 2017 – 3 –
5.21 Frequency channel . 47
5.22 Frequency hopping procedure . 48
5.23 Future expansion plan . 48
5.24 Geographical dimension of the plant . 48
5.25 Infrastructure device . 48
5.26 Initiation of data transmission . 48
5.27 ISM application . 49
5.28 Length of user data per transfer interval. 49
5.29 Limitation from neighbours of the plant . 49
5.30 Maximum number of retransmissions . 49
5.31 Mechanism for adaptivity . 49
5.32 Medium access control mechanism . 50
5.33 Modulation . 50
5.34 Natural environmental condition . 50
5.35 Network topology . 50
5.36 Packet loss rate . 51
5.37 Position of wireless devices . 51
5.38 Power spectral density . 51
5.39 Purpose of the automation application . 52
5.40 Receiver blocking . 52
5.41 Receiver input level . 52
5.42 Receiver sensitivity . 53
5.43 Regional radio regulations . 53
5.44 Relative movement . 53
5.45 Response time . 53
5.46 Security level . 54
5.47 Spatial coverage of the wireless communication network . 54
5.48 Spurious response . 54
5.49 Total radiated power . 54
5.50 Transfer interval . 54
5.51 Transmission gap . 55
5.52 Transmission time . 56
5.53 Transmitter output power . 59
5.54 Transmitter sequence . 59
5.55 Transmitter spectral mask . 60
5.56 Update time . 60
5.57 Wireless device density . 61
5.58 Wireless communication network density . 61
5.59 Wireless technology or standard . 62
6 Coexistence management information structures . 62
6.1 General . 62
6.2 General plant characteristic . 63
6.3 Application communication requirements . 64
6.3.1 Overview . 64
6.3.2 Requirements influencing the characteristic of wireless solutions . 65
6.3.3 Performance requirements . 66
6.4 Characteristic of wireless system type and wireless device type . 66
6.4.1 Overview . 66
6.4.2 Wireless system type . 67

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6.4.3 Wireless device type . 67
6.5 Characteristic of wireless solution . 70
6.5.1 Overview . 70
6.5.2 Characteristic of a wireless network solution. 70
6.5.3 Characteristic of a wireless device solution . 71
7 Coexistence management process . 72
7.1 General . 72
7.1.1 Overview . 72
7.1.2 Documentation . 72
7.1.3 Suitable documentation method . 75
7.1.4 Application of tools . 76
7.2 Establishment of a coexistence management system . 76
7.2.1 Nomination of a coexistence manager . 76
7.2.2 Responsibility of a coexistence manager . 77
7.2.3 Support by radio experts . 77
7.2.4 Training . 77
7.3 Maintaining coexistence management system . 78
7.4 Phases of a coexistence management process . 78
7.4.1 Investigation phase . 78
7.4.2 Planning phase . 81
7.4.3 Implementation phase. 83
7.4.4 Operation phase . 84
8 Coexistence parameter templates . 86
Bibliography . 90

Figure 1 – Issues of consideration . 25
Figure 2 – Applications using frequency spectrum . 26
Figure 3 – Progression of expense to achieve coexistence corresponding to the
application classes . 30
Figure 4 – Separation of wireless systems according to frequency and time . 33
Figure 5 – Coexistence conceptual model . 35
Figure 6 – Flow chart of the coexistence conceptual model . 36
Figure 7 – Selection of a wireless system in the coexistence management process . 37
Figure 8 – Communication load in case of two wireless devices . 41
Figure 9 – Communication load in the case of several wireless devices . 42
Figure 10 – Cut-off frequencies derived from maximum power level . 43
Figure 11 – Distance of the wireless devices . 44
Figure 12 – Duty cycle . 45
Figure 13 – Maximum dwell time . 46
Figure 14 – Power spectral density of an IEEE 802.15.4 system . 52
Figure 15 – Communication cycle, application event interval and machine cycle . 55
Figure 16 – Minimum transmission gap . 56
Figure 17 – Example of the density functions of transmission time . 57
Figure 18 – Example of the distribution functions of transmission time . 58
Figure 19 – Transmitter sequence . 59
Figure 20 – Transmitter spectral mask of an IEEE 802.15.4 system . 60

IEC 62657-2:2017 © IEC 2017 – 5 –
Figure 21 – Example of distribution functions of the update time . 61
Figure 22 – Principle for use of coexistence parameters . 63
Figure 23 – Parameters to describe the general plant characteristic . 63
Figure 24 – Parameters to describe application communication requirements . 65
Figure 25 – Parameters to describe wireless network type and device type . 66
Figure 26 – Power spectral density and transmitter spectral mask of a DECT system . 68
Figure 27 – Medium utilization in time and frequency of a DECT system . 68
Figure 28 – Parameters to describe a wireless solution . 70
Figure 29 – Relations of the documents in a coexistence management system
specification. 75
Figure 30 – Planning of a wireless system in the coexistence management process . 82
Figure 31 – Implementation and operation of a wireless system in the coexistence
management process . 85

Table 1 – Example of a classification of application communication requirements . 24
Table 2 – Application profile dependent observation time values . 45
Table 3 – Parameter options for frequency channel . 48
Table 4 – List of parameters used to describe the general plant characteristic . 64
Table 5 – List of parameters used to describe the requirements influencing the
characteristic of wireless solutions . 65
Table 6 – List of parameters used to describe performance requirements . 66
Table 7 – List of parameters used to describe the wireless system type . 67
Table 8 – List of parameters used to describe the transmitter of a wireless device type . 69
Table 9 – List of parameters used to describe the receiver of a wireless device type . 69
Table 10 – List of parameters used to describe a wireless network solution . 70
Table 11 – List of parameters used to describe the transmitter of a wireless device
solution . 71
Table 12 – List of parameters used to describe the receiver of a wireless device
solution . 72
Table 13 – Template used to describe the general plant characteristic . 86
Table 14 – Template used to describe the application communication requirements . 87
Table 15 – Template used to describe the wireless system type . 87
Table 16 – Template used to describe a wireless device type . 88
Table 17 – Template used to describe the wireless network solution . 88
Table 18 – Template used to describe a wireless device solution . 89
Table 19 – Template used to describe an ISM application . 89

– 6 – IEC 62657-2:2017 © IEC 2017
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
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2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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6) All users should ensure that they have the latest edition of this publication.
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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.
This second edition cancels and replaces the first edition published in 2013. This edition
constitutes a technical revision.
This second edition includes the following significant technical changes with respect to the
previous edition:
a) update of the normative references, terms, definitions, symbols and abbreviations;
b) addition of terms;
IEC 62657-2:2017 © IEC 2017 – 7 –
c) checking of the life-cycle terms of this document versus the terms used in IEC 62890:—
and addition of explanations;
d) addition and modification of text to make the text more readable;
e) alignment of some definitions and specifications of coexistence parameters in order to
facilitate their future inclusion in the IEC Common Data Dictionary (IEC CDD) maintained
by the IEC.
The text of this standard is based on the following documents:
FDIS Report on voting
65C/861/FDIS 65C/873/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.
A list of all the 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 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.
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.
___________
Under preparation. Stage at the time of publication: IEC/AFDIS 62890:2017.

– 8 – IEC 62657-2:2017 © IEC 2017
INTRODUCTION
The overall market for wireless network solutions spans a range of diverse applications, with
differing performance and functional requirements. Within this overall market, the industrial
automation domain could include:
• process automation, covering for example the following industry branches:
– oil and gas, refining,
– chemical,
– pharmaceutical,
– mining,
– pulp & paper,
– water & wastewater,
– steel
• electric power such as:
– power generation (for example wind turbine),
– power transmission and distribution (grid),
• factory automation, covering for example the following industry branches:
– food and beverage,
– automotive,
– machinery,
– semiconductor.
Industrial automation requirements for wireless networks are different from those of, for
example, the telecommunications, commercial and consumer markets. These industrial
automation requirements are identified and provided in IEC 62657-1.
Industrial premises may contain a variety of wireless network technologies and other sources
of radio frequency emissions.
This document is intended for designers and persons responsible for production and process
plants, system integrators and mechanical engineers having to integrate and start up wireless
systems in machines and plants, and producers of industrial wireless solutions. In particular, it
is intended to motivate exchange of information between automation and radio engineers.
Many wireless industrial automation applications are also located in physical environments
over which the operator/owner can exert control. That is, within a physical facility where the
presence and operation of all radio frequency emitting devices are under the control of a
single entity. This allows wireless management strategies to be employed which are not
feasible for equipment installed in public or other unmanaged areas.

IEC 62657-2:2017 © IEC 2017 – 9 –
In industrial automation, many different wireless networks may operate in the same premises. ®
2 3
Examples of these networks are IEC 62591 [8] (WirelessHART ), IEC 62601 [9] (WIA-PA)
and IEC 62734 [10] (ISA100.11a); all these networks use IEEE 802.15.4 [19] for the process
automation applications. Other examples of wireless networks are specified in IEC 61784-1
[4] and IEC 61784-2 [5] CPs that use IEEE 802.11 [17] and IEEE 802.15.1 [18] for factory
automation applications. Different to wired fieldbuses, the wireless communication devices
can interfere with others on the same premises or environment, disturbing each other. Other
sources of radio frequency energy in these bands, often at high energy levels, include radio-
frequency process heating, plastic welding, plasma lamps, and microwave irradiation devices.
Clearly, without a means to manage the coexistence of these varied emitters, it would be
problematic to ensure that wireless networks meet the time-criticality and other performance
requirements of industrial automation.
The IEC 62657 series has two parts:
• Part 1: Wireless communication requirements and spectrum considerations
• Part 2: Coexistence management
IEC 62657-1 provides general requirements for industrial automation and spectrum
considerations that are the basis for industrial communication solutions. This document
specifies the coexistence management of wireless devices to ensure predicable performance.
It is intended to facilitate harmonization of future adjustments to international, national, and
local regulations.
This document 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 document describes
mechanisms to manage the potential mutual interference that might occur due to the
operation of multiple wireless devices in a plant.
This document provides guidance to the users of wireless networks on selection and proper
use of wireless networks. To provide suitable wireless devices to the market, it also serves
vendors in describing the behaviours of wireless devices to build wireless networks matching
the application requirements.
This document 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.

___________
Numbers in square brackets refer to the bibliography.
WirelessHART is the registered trade name of the FieldComm Group, see www.fieldcommgroup.org. 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.

– 10 – IEC 62657-2:2017 © IEC 2017
INDUSTRIAL COMMUNICATION NETWORKS –
WIRELESS COMMUNICATION NETWORKS –

Part 2: Coexistence management

1 Scope
This document:
• specifies the fundamental assumptions, concepts, parameters, and procedures 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 document provides a major contribution to national and regional regulations. It does not
exempt devices from conforming to all requirements of national and regional regulations.
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 62657-1:— , Industrial communication networks – Wireless communication networks –
Wireless communication requirements and spectrum considerations
IEC 62443 (all parts), Industrial communication networks – Network and system security
3 Terms, definitions, abbreviated terms and conventions
3.1 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:
___________
Under preparation. Stage at the time of publication: IEC/RFDIS 62657-1:2017.

IEC 62657-2:2017 © IEC 2017 – 11 –
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1.1
adjacent channel interference
interference that occurs from wireless devices using adjacent frequency channels
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 type
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] [21]
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
industrial automation application
application of measurement and automatic control in the industrial automation domain
3.1.7
automation application data length
user data length
number of octets that are exchanged at the reference interface
3.1.8
availability,
ability of an item to be in a state to perform as required function under given conditions at a
given instant of time or over a given time interval, assuming that the required external
resources are provided
Note 1 to entry: This ability depends on the combined aspects of the reliability performance, the maintainability
performance, and the maintenance support performance.
Note 2 to entry: Required external resources, other than maintenance resources, do not affect the availability
performance of the item.
[SOURCE: IEC 60050-191:1990, 191-02-05]
3.1.9
bandwidth
difference between upper cut-off frequency and lower cut-off frequency

– 12 – IEC 62657-2:2017 © IEC 2017
3.1.10
cellular topology
cellular network topology
network topology where the geographical area is divided in cells
Note 1 to entry: A device can move from one cell to another cell. Devices that are in a cell communicate through
a central hub. Hubs in different cells are interconnected.
3.1.11
centre frequency
geometric mean of lower cut-off frequency and upper cut-off frequency of a frequency channel
3.1.12
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.
3.1.13
coexistence
wireless communication coexistence
state in which all wireless communication solutions of a plant using shared medium fulfil all
their application communication requirements
Note 1 to entry: In IEEE 802.15.2-2003 [19] the coexistence is defined as a characteristic of a device.
3.1.14
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
3.1.15
coexistence management
process to establish and to maintain coexistence that includes technical and organizational
measures
3.1.16
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
3.1.17
communication load
amount of user data to be transmitted from the automation application within a certain period
of time
3.1
...