IEC 62657-2:2017/AMD1:2019
(Amendment)Amendment 1 - Industrial communication networks - Wireless communication networks - Part 2: Coexistence management
Amendment 1 - Industrial communication networks - Wireless communication networks - Part 2: Coexistence management
Amendement 1 - Réseaux de communication industriels - Réseaux de communication sans fil - Partie 2: Gestion de coexistence
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IEC 62657-2
®
Edition 2.0 2019-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
A MENDMENT 1
AM ENDEMENT 1
Industrial communication networks – Wireless communication networks –
Part 2: Coexistence management
Réseaux de communication industriels – Réseaux de communication sans fil –
Partie 2: Gestion de coexistence
IEC 62657-2:2017-05/AMD1:2019-09(en-fr)
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IEC 62657-2
®
Edition 2.0 2019-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
A MENDMENT 1
AM ENDEMENT 1
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; 33.040.40; 35.110 ISBN 978-2-8322-7266-4
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® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
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– 2 – IEC 62657-2:2017/AMD1:2019
© IEC 2019
FOREWORD
This amendment has been prepared by subcommittee 65C: Industrial networks, of IEC
technical committee 65: Industrial-process measurement, control and automation.
The text of this amendment is based on the following documents:
FDIS Report on voting
65C/968/FDIS 65C/976/RVD
Full information on the voting for the approval of this amendment can be found in the report
on voting indicated in the above table.
The committee has decided that the contents of this amendment and the base publication will
remain unchanged until the stability date indicated on the IEC website under
"http://webstore.iec.ch" in the data related to the specific publication. At this date, the
publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
_____________
INTRODUCTION
This Amendment 1 to the second edition includes the following significant technical changes:
a) 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.
3 Terms, definitions, abbreviated terms and conventions
3.1 Terms and definitions
Replace the existing terms and definitions by the following:
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
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© IEC 2019
3.1.3
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 – Deletion of “loss-free” before “reference
antenna”, deletion of the two notes and synonyms] [21]
3.1.4
antenna radiation pattern
variation of the field intensity of an antenna as an angular function with respect to the axis
3.1.5
antenna type
structure or device used to collect or radiate electromagnetic waves
3.1.6
application communication requirements
quantitative requirements specifying the required conditions and the required characteristics
of wireless communication solutions at the communication interface that is met in order to
achieve the purpose of the automation application
3.1.7
automation application
industrial automation application
application of measurement and automatic control in the industrial automation domain
3.1.8
automation application data length
user data length
number of octets that are exchanged at the reference interface
3.1.9
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, modified – Deletion of third note to entry]
3.1.10
bandwidth
frequency bandwidth
difference between upper cut-off frequency and lower cut-off frequency
3.1.11
bit rate of the physical link
measure of the number of binary digits transferred per second
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3.1.12
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.
3.1.13
center frequency
geometric mean of lower cut-off frequency and upper cut-off frequency of a frequency channel
3.1.14
channel number
unsigned integer number identifying a wireless communication channel in accordance to an
authoritative document or rule
3.1.15
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.
3.1.16
characteristic of the area of operation
distinguishing properties of the area where the wireless communication network is operated
3.1.17
characteristic of wireless communication solution
parameters of wireless communication solutions which are implementations of wireless
communication systems and devices
3.1.18
characteristic of wireless device solution
parameters related to individual nodes within a network implementing a wireless
communication solution
3.1.19
characteristic of wireless device type
specification of transmitter and receiver parameters
3.1.20
characteristic of wireless network solution
parameters related to a network as a whole used implementing a wireless communication
solution
3.1.21
characteristic of wireless system type
parameters describing the kind of wireless communication system
3.1.22
characteristic of wireless system type and wireless device type
parameters that characterize the model of a wireless system or a wireless device by providing
the parameters to specify a wireless system type and a wireless device type
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IEC 62657-2:2017/AMD1:2019 – 5 –
© IEC 2019
3.1.23
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.
3.1.24
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
3.1.25
coexistence management
process to establish and to maintain coexistence that includes technical and organizational
measures
3.1.26
coexistence management information
parameters for the wireless coexistence management process
3.1.27
coexistence manager
role of a nominated person to manage coexistence
3.1.28
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
3.1.29
communication load
amount of user data to be transmitted from the automation application within a certain period
of time
3.1.30
cut-off frequency
frequency limit, nearest to the frequency where the spectral power density drops below a
certain level, defining the frequency bandwidth
3.1.31
data throughput
ratio of the number of user data per time period, transferred within a consumer at the
reference interface to the application
3.1.32
device type information
manufacturer name, manufacturer contact, the type and version of hardware and software
3.1.33
distance between wireless devices
geographical distance between devices within a three-dimensional space
3.1.34
duty cycle
ratio of the transmitter sequence referenced to a given observation time for the used
frequency channel
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3.1.35
dwell time
period spent at a particular frequency during any single hop of a frequency hopping system
3.1.36
equivalent isotropic radiated power
product of the power supplied to the antenna and the antenna gain in a given direction
relative to an isotropic antenna (absolute or isotropic gain)
[SOURCE: Radio Regulations (2012) – Art. 1 § 1.161, modified – Term modified from
isotropically to isotropic and definition reformatted according to the ISO/IEC Directives Part 2]
3.1.37
effective radiated power
product of the power supplied to the antenna and its gain relative to a half-wave dipole in a
given direction
[SOURCE: Radio Regulations (2012) – Art. 1 § 1.162, modified – Deleted “(in a given
direction)” and definition reformatted according to the ISO/IEC Directives Part 2]
3.1.38
electromagnetic interference
EMI
degradation of the performance of an equipment, transmission channel or system caused by
an electromagnetic disturbance
Note 1 to entry: In French, the terms "perturbation électromagnétique" and "brouillage électromagnétique"
designate respectively the cause and the effect, and should not be used indiscriminately.
Note 2 to entry: In English, the terms "electromagnetic disturbance" and "electromagnetic interference" designate
respectively the cause and the effect, and should not be used indiscriminately.
[SOURCE: IEC 60050-161:1990/AMD1:1997, 161-01-06, modified – Corrected mistakes in the
Notes to entry]
3.1.39
frequency band
range in the frequency spectrum that is assigned by regulatory organizations for use for
specific applications or a group of applications
Note 1 to entry: The ITU as international regulatory organization assigns only radio communication services to a
specific range in the frequency spectrum.
3.1.40
frequency channel
span of the frequency spectrum which is characterized by lower cut-off frequency and upper
cut-off frequency or by center frequency and bandwidth
3.1.41
frequency hopping procedure
sequence of frequency channels used for transmission (hopping sequence) and dwell time
3.1.42
future expansion plan
possible installation of new wireless communication solutions and buildings that can affect
coexistence
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IEC 62657-2:2017/AMD1:2019 – 7 –
© IEC 2019
3.1.43
general plant characteristics
parameters that characterizes the plant in general with respect to all wireless communication
applications
3.1.44
geographical dimension of the plant
length, width and height of the intended space of the wireless system
3.1.45
industrial automation application
control or management systems used in industrial production, including supervisory control
and data acquisition systems, distributed control systems, and other control system
configurations often found in the industrial sectors and critical infrastructures
3.1.46
industrial communication network
data communications sub-systems for industrial-process measurement and control as well as
on instrumentation systems used for research, development or testing purposes
3.1.47
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.
3.1.48
infrastructure device
device that is essential for building up a wireless communication system according to a
technology or standard, but not having an interface to an automation application
EXAMPLE Router or base stations without interfaces to the wired industrial network or without automation
application functions.
3.1.49
initiation of data transmission
method that specifies how the application initiates the data transfer
3.1.50
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
3.1.51
interference
radio frequency interference
effect of unwanted energy due to one or a combination of emissions, radiations, or inductions
upon reception in a radio communication system, manifested by any performance
degradation, misinterpretation, or loss of information which could be extracted in the absence
of such unwanted energy
[SOURCE: Database ITU Terms and Definitions]
3.1.52
industrial, scientific and medical application
operation of equipment or appliances designed to generate and use locally radio frequency
energy for industrial, scientific, medical, domestic or similar purposes, excluding applications
in the field of telecommunications
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[SOURCE: Radio Regulations (2012) – Art. 1 § 1.15]
3.1.53
jitter
time variation of an expected occurrence
Note 1 to entry: Examples are variation of transmission time and update time.
3.1.54
length of user data per transfer interval
number of the octets sent out during a transfer interval, where the octets that are added
because of the requirements of the wireless communication protocol are subtracted
Note 1 to entry: The application data length affects the communication load and might account for the temporal
separation of the wireless communication systems.
3.1.55
life-cycle
length of time from the start of the development phase of a product type to the product
abandonment
1
[SOURCE: IEC 62890:— , 3.1.19]
3.1.56
limitation from neighbours of the plant
description of the neighbors of the plant that are likely to cause limitations for wireless
communication
EXAMPLE High power radio source(s).
3.1.57
linear topology
linear network topology
topology where the nodes are connected in series, with two nodes connected to only one
other node and all others each connected to two other nodes (that is, connected in the shape
of a line)
Note 1 to entry: This topology corresponds to that of an open ring.
[SOURCE: IEC 61918:2013, 3.1.44, modified – Added an admitted term]
3.1.58
lower cut-off frequency
frequency furthest below the frequency of maximum power where the power spectral density
drops below a certain level
3.1.59
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
3.1.60
maximum number of retransmissions
upper limit of how many times user data are allowed being retransmitted automatically by the
communication stack because of transmission errors
____________
1
Under preparation. Stage at the time of publication: IEC 62890/FDIS:2019.
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© IEC 2019
3.1.61
mechanism for adaptivity
technique or procedure to increase coexistence capability
3.1.62
medium access control mechanism
transmission technique how to access the medium
Note 1 to entry: Examples are CSMA, TDMA, or combination of both.
3.1.63
mesh topology
mesh network topology
topology in which redundant physically-diverse routing paths are available between each pair
of network nodes
Note 1 to entry: Wireless mesh topology is usable to extend coverage via multi-hop capability and/or to facilitate
communication reliability by providing redundant paths between devices.
[SOURCE: IEC 62734:2014, 3.1.2.95, modified – Added an admitted term]
3.1.64
metrics
set of quantitative indicators corresponding to selected properties of a communication device,
equipment, or wireless communication system
3.1.65
modulation
process of varying one or more properties of a periodic waveform with a modulating signal
that contains information to be transmitted
3.1.66
natural environmental condition
condition that surrounds the wireless device and wireless system
Note 1 to entry: Examples are temperature, humidity, air pressure.
3.1.67
network
all of the media, connectors, repeaters, routers, gateways and associated node
communication elements by which a given set of communicating devices are interconnected
[SOURCE: IEC 61158-2:2014, 3.1.30]
3.1.68
node
end-point of a branch in a network
[SOURCE: IEC 61918:2013, 3.1.50]
3.1.69
other frequency user
user which generates and uses radio frequency energy without having the objective of
telecommunication
Note 1 to entry: Examples are welding machine, electrical drive and frequency converter.
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3.1.70
out-of-band emission
emission on a frequency or frequencies immediately outside the necessary bandwidth which
results from the modulation process, but excluding spurious emissions
[SOURCE: Radio Regulations (2012) – Art. 1 § 1.144]
3.1.71
packet loss rate
ratio of number of packets, transferred from the application at the reference interface within
the producer, and the number of packets, transferred at the reference interface to the
application within the consumer
3.1.72
performance requirements
requirements describing the time and error behavior necessary to achieve the purpose of the
automation application
3.1.73
physical link
relation between radio transceivers (physical end points) of two wireless devices
3.1.74
plant
managed facility, typically with a physically protected perimeter, hosting the physical process,
operation, personnel, equipment
3.1.75
point-to-point topology
point-to-point network topology
topology where two nodes are directly connected to each other
3.1.76
position of wireless device
geographical position of the three dimensional space in absolute or relative coordinates where
the device is located
3.1.77
power spectral density
distribution as a function of frequency of the power per unit bandwidth of the spectral
components of a signal or a noise having a continuous spectrum and a finite mean power
[SOURCE: IEC 60050-713:1998,713-09-12]
3.1.78
purpose of the automation application
summary of the automation application supported by the wireless network to the extent
needed to provide a useful overview of the requirements imposed on the wireless network
3.1.79
radio channel
model considers the characteristic of the frequency channel, the environmental conditions, the
distance between the wireless devices, the antenna characteristic
3.1.80
radio resource
means used by multiple wireless communication solutions for the purpose of radio signal
transmission
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© IEC 2019
3.1.81
radio robustness
attribute of wireless communication to fulfil the designated function despite the presence of
other active wireless 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 [19].
3.1.82
reference interface
exposed interface between an automation application and the wireless communication
function
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.
3.1.83
receiver blocking
effect of a strong interfering signal on the receiver’s ability to detect a low-level wanted signal
3.1.84
receiver input level
received signals with levels above the receiver maximum input level
3.1.85
receiver maximum input level
maximum signal power that the system can tolerate without distortion of the signal
3.1.86
receiver sensitivity
minimal signal power to receive data with a defined bit error rate
3.1.87
regional radio regulation
regulation of important coexistence parameters such as frequency band and output power
related to the region where the wireless application is intended to be used
3.1.88
relative movement
position of a wireless device over time
3.1.89
requirements influencing the characteristic of wireless solutions
application communication requirements that influence the performance of wireless solutions
and thus the coexistence state
3.1.90
response time
time interval between the instant delivery of the first user data bit, or octet, of a packet to the
reference interface of a transmitter, and the instant when the last bit, or octet, of the
confirmation packet is delivered at the reference interface of the same transmitter, which can
be assigned to the request
3.1.91
ring topology
ring network topology
active network where each node is connected in series to two other nodes
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© IEC 2019
[SOURCE: IEC 61918:2013, 3.1.63, modified – ring" has been changed to "ring topology" and
an admitted term has been added]
3.1.92
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.
3.1.93
security level
requirement category for cyber security
3.1.94
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 document. The frequency bands are used by diverse ISM
applications and wireless communication applications.
3.1.95
spatial coverage of the wireless communication network
spatial coverage specified by length, width and height of a cuboid that encloses the wireless
communication network
3.1.96
spurious emission
emission on a frequency or frequencies which are outside the necessary bandwidth and the
level of which may be reduced without affecting the corresponding transmission of
information, including harmonic emissions, parasitic emissions, intermodulation products and
frequency conversion products, but exclude out-of-band emissions
[SOURCE: Radio Regulations (2012) – Art. 1 § 1.145]
3.1.97
spurious response
receiver output due to unwanted signals
Note 1 to entry: That means having frequencies other than those of the tuned frequency channel.
3.1.98
star topology
star network topology
network of three or more devices topology where all devices are connected to a central device
[SOURCE: IEC 61918:2013, 3.1.69, modified – "topology" has been added, "point (which may
be active or passive)" has been replaced by "device", and an admitted term has been added]
3.1.99
telecommunication
any transmission, emission or reception of signs, signals, writings, images and sounds or
intelligence of any nature by wire, radio, optical or other electromagnetic systems
[SOURCE: Radio Regulations (2012) – Art. 1 § 1.3]
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3.1.100
topology of a network
network topology
pattern of the relative positions and interconnections of the individual elements of the network
[SOURCE: IEC 61918:2013, 3.1.73, modified – Deleted the “Note 1 to entry” and added an
admitted term]
3.1.101
total radiated power
spatial power density integrated across the surface of the sphere
3.1.102
transfer interval
time difference between two consecutive transfers of user data from the automation
application via the reference interface to the wireless communication function
3.1.103
transmission gap
gap between two successive channel usages by a transmitter
3.1.104
transmission time
interval from starting the delivery of the first application data octet of
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