ISO/IEC 4005-3:2023

Telecommunications and information exchange between systems — Unmanned aircraft area network (UAAN) — Part 3: Physical and data link protocols for control communication

This document specifies communication protocols for the physical and data link layer for control communication, which is wireless distributed communication network for units related with unmanned aircrafts (UAs) in level II. This document describes control communication, which is one-to-one communication between a UA and a controller.

Télécommunications et échange d'information entre systèmes — Réseau de zone de drones (Unmanned aircraft area network - UAAN) — Partie 3: Protocoles de liaison de données et physiques pour la communication de contrôle

General Information

• Status: Published
• Publication Date: 21-Mar-2023
• ICS: 35.100.10 - Physical layer
• ICS: 35.100.20 - Data link layer
• ICS: 49.020 - Aircraft and space vehicles in general
• Technical Committee: ISO/IEC JTC 1/SC 6 - Telecommunications and information exchange between systems
• Drafting Committee: ISO/IEC JTC 1/SC 6/WG 1 - Physical and data link layers
• Current Stage: 6060 - International Standard published
• Start Date: 22-Mar-2023
• Due Date: 09-Feb-2023
• Completion Date: 22-Mar-2023

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 4005-3
First edition
2023-03
Telecommunications and information
exchange between systems —
Unmanned aircraft area network
(UAAN) —
Part 3:
Physical and data link protocols for
control communication
Télécommunications et échange d'information entre systèmes —
Réseau de zone de drones (Unmanned aircraft area network -
UAAN) —
Partie 3: Protocoles de liaison de données et physiques pour la
communication de contrôle
Reference number
ISO/IEC 4005-3:2023(E)
© ISO/IEC 2023

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ISO/IEC 4005-3:2023(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO/IEC 2023
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
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ISO/IEC 4005-3:2023(E)
Contents Page
Foreword .v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 1
5 Physical layer . 2
5.1 Channel and frame structure for data channel . 2
5.1.1 Number of data channels and bandwidth . 2
5.1.2 Frame structure . 2
5.1.3 Slot transmit time mask . . 3
5.1.4 Subchannels . 3
5.1.5 Initial work resources (IWR) and channel . 4
5.1.6 Dedicated slots and dedicated subchannels . 5
5.2 Channel and frame structure for tone channel . 5
5.2.1 Frame structure and bandwidth . 5
5.2.2 Slot transmit power . 6
5.2.3 Slot block structure . 6
5.2.4 Subslot transmission time mask . 8
5.2.5 Subslot signal waveform. 8
5.3 Encoding procedure . 9
5.4 Physical layer procedure . 9
5.4.1 Synchronization . 9
5.4.2 Subchannel power . 9
5.4.3 Measurements . 9
5.4.4 Coexistence operation . 9
6 Data link layer .10
6.1 General . 10
6.2 Channel mapping and measurements.12
6.2.1 General .12
6.2.2 Mapping of communication resources and subslot sets.12
6.2.3 Interference power calculation . 13
6.2.4 Subchannel map . 14
6.3 Subchannel negotiation for allocation . 14
6.3.1 General . 14
6.3.2 Subchannel negotiation using shared channel . 19
6.3.3 Subchannel negotiation using dedicated slot . 21
6.3.4 Subchannel negotiation using IWR . 23
6.4 Resource allocation competition and generated link confirmation . 26
6.4.1 General . 26
6.4.2 Subchannel resource allocation competition . 27
6.4.3 Generated link confirmation .29
6.4.4 Broadcasting control channel information being allocated or occupied . 31
6.5 Subchannel occupation and collision management . 32
6.5.1 General . 32
6.5.2 Subchannel occupation and return . 32
6.5.3 Collision tone transmission and collision management . 32
6.5.4 Power control in occupation stage .34
6.6 Reallocation . . 35
6.6.1 General . 35
6.6.2 Reallocation decision . 35
6.6.3 Subchannel reallocation procedure .38
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ISO/IEC 4005-3:2023(E)
6.7 Data exchange . 39
6.7.1 General .39
6.7.2 Data packet format . 39
6.8 Synchronization . 43
6.9 Data link layer security . 43
6.10 Interface with upper layers . 45
6.10.1 General . 45
6.10.2 Initialization interface. 45
6.10.3 Dynamic interface . 51
6.11 Interface with other communication layer . 55
6.11.1 General . 55
6.11.2 Interface with SC . 55
6.11.3 Interface with VC . .56
Bibliography .59
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ISO/IEC 4005-3:2023(E)
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are
members of ISO or IEC participate in the development of International Standards through technical
committees established by the respective organization to deal with particular fields of technical
activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other international
organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the
work.
The procedures used to develop this document and those intended for its further maintenance
are described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria
needed for the different types of document should be noted. This document was drafted in
accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives or
www.iec.ch/members_experts/refdocs).
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent
rights. Details of any patent rights identified during the development of the document will be in the
Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents) or the IEC
list of patent declarations received (see https://patents.iec.ch).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see
www.iso.org/iso/foreword.html. In the IEC, see www.iec.ch/understanding-standards.
This document was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 6, Telecommunications and information exchange between systems.
A list of all parts in the ISO/IEC 4005 series can be found on the ISO and IEC websites.
Any feedback or questions on this document should be directed to the user’s national standards
body. A complete listing of these bodies can be found at www.iso.org/members.html and
www.iec.ch/national-committees.
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ISO/IEC 4005-3:2023(E)
Introduction
Unmanned aircrafts (UAs) operating at low altitudes will provide a variety of commercial services in
the near future. UAs that provide these services are distributed in the airspace. In low uncontrolled
airspace, many people operate their own UAs without the assignment of communication channels from
a central control centre.
This document describes control communication, which is a wireless distributed communication. Control
communication allows control pairs of UA and controller distributed over the airspace to communicate
with each other without serious interference. The channel used for control communication has a multi-
channel structure, which enables UAs and controllers to independently use the communication link
occupied by each other. A wireless distributed communication described by this document is intended
to be used in licensed frequency bands.
The ISO/IEC 4005 series consists of the following four parts:
ISO/IEC 4005-1: To support various services for UAs, it describes a wireless distributed communica-
tion model and the requirements that this model shall satisfy.
ISO/IEC 4005-2: It describes communication in which all units involved in UA operation can broad-
cast or exchange information by sharing communication resources with each other.
ISO/IEC 4005-3 (this document): It describes the control communication for the controller to con-
trol the UA.
ISO/IEC 4005-4: It describes video communication for UAs to send video to a controller.
The International Organization for Standardization (ISO) and International Electrotechnical
Commission (IEC) draw attention to the fact that it is claimed that compliance with this document may
involve the use of patents.
ISO and IEC take no position concerning the evidence, validity and scope of these patent rights.
The holders of these patent rights have assured ISO and IEC that they are willing to negotiate licences
under reasonable and non-discriminatory terms and conditions with applicants throughout the world.
In this respect, the statements of the holders of these patent rights are registered with ISO and IEC.
Information may be obtained from the patent database available at www.iso.org/patents.
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights other than those in the patent database. ISO and IEC shall not be held responsible for
identifying any or all such patent rights.
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INTERNATIONAL STANDARD ISO/IEC 4005-3:2023(E)
Telecommunications and information exchange between
systems — Unmanned aircraft area network (UAAN) —
Part 3:
Physical and data link protocols for control communication
1 Scope
This document specifies communication protocols for the physical and data link layer for control
communication, which is wireless distributed communication network for units related with unmanned
aircrafts (UAs) in level II.
This document describes control communication, which is one-to-one communication between a UA
and a controller.
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.
ISO/IEC 4005-1, Telecommunications and information exchange between systems — Unmanned aircraft
area network (UAAN) — Part 1: Communication model and requirements
ISO/IEC 4005-2:2023, Telecommunications and information exchange between systems — Unmanned
aircraft area network (UAAN) — Part 2: Physical and data link protocols for shared communication
ISO/IEC 4005-4, Telecommunications and information exchange between systems — Unmanned aircraft
area network (UAAN) — Part 4: Physical and data link protocols for video communication
ISO 21384-4, Unmanned aircraft systems — Part 4: Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions defined in ISO/IEC 4005-1, ISO/IEC 4005-2,
ISO 21384-4 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
subchannel map
2-bit string indicating whether subchannels are available
Note 1 to entry: In wireless distributed communication, the subchannel map of each unit is generally different.
4 Abbreviated terms
CC Control Communication
1
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ISO/IEC 4005-3:2023(E)
CRC Cyclic Redundancy Check
CSCH Control Subchannel
DLL Data Link Layer
DS Dedicated Slot
FN Frame Number
IWR Initial Work Resource
LFSR Linear Feedback Shift Register
PB Parsing Block
PKH Packet Header
PN Pseudo Noise
SA Source Address
SC Shared Communication
TSB Tone Slot Block
TX Transmission
UTC Coordinated Universal Time
VC Video Communication
VSCH Video Subchannel
5 Physical layer
5.1 Channel and frame structure for data channel
5.1.1 Number of data channels and bandwidth
The number of data channels is N as shown in Figure 1. N is greater than or equal to one. The bandwidth
of one data channel is 1,25 MHz. The N is determined in the upper layer.
Figure 1 — Data channels in frequency region
5.1.2 Frame structure
The frame length of the data channel is 1 sec and consists of 500 slots and one slot time T is 2 ms as
s
shown in Figure 2. FN is a frame number that varies from 0 to 59 and has the same value as the second
of the current time.
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ISO/IEC 4005-3:2023(E)

a
1 frame, T = 1 sec = 500 T
f s.
b
1 slot, T = 2 ms.
s
Figure 2 — Frame structure of the control channel
5.1.3 Slot transmit time mask
The transmission time mask of a slot is shown in Figure 3.

a
2 ms.
b
Modulated signal.
Figure 3 — The transmission time mask of a slot
T , T , T , T are symbol offsets from T and symbol time is 1/672000 sec. Each value is as follows: T is
1 2 3 4 0 1
2, T is 1297, T is 1299, T is 1344.
2 3 4
T is 0 μs as the start time of the slot and the power amplifier is gated on and unmodulated fine signals
0
begin to be transmitted. T is an offset at which modulation signal transmission starts. T is an offset
1 2
at which the transmission of the modulated signal ends. T is an offset at which the power amplifier is
3
gated off, and transmission of unmodulated fine signals is stopped. The transmit power of T to T , T to
0 1 2
T shall be at least 50 dB less than the modulation signal transmit power.
3
5.1.4 Subchannels
5.1.4.1 General
One data channel consists of 20 subchannels as shown in Figure 4. Subchannel y of control channel x is
composed of the following slot set.
CCH = S , S , S , …, S
x,y x,z x,z+20 x,z+40 x,z+480
ye, venframe
z = (1)
yy+(2m− od 4)/2 ×4,  oddframe
 
where
y is subchannel number, y=0, 1, …, 19;
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ISO/IEC 4005-3:2023(E)
S is slot z of control channel x.
x,z


a
CCH
x
b
CCH
x,0
c
CCH
x,1
d
CCH
x,18
e
CCH
x,19
Figure 4 — Subchannel structure of control communication in even frame
A subchannel consists of 25 slots, the i-th slot resource of the subchannel y of the channel x is indicated
by SR and the subchannel y of frequency channel x is indicated by CCH . Therefore, CCH is as
x,y,i x,y x,y
follows.
CCH =…SR ,,SR ,SR (2)
xy,,xy ,,01xy ,,xy ,24
where SR is i-th slot resource of subchannel y of channel x, i=0, …, 24.
x,y,i
5.1.4.2 Up and down link decision of slot resources
For SR , 5 slots satisfying (i mod 5) =(FN mod 5) are downlink and remain 20 slots are uplink, where
x,y,i
mod means modulo operation.
5.1.5 Initial work resources (IWR) and channel
The upper layer can set the initial work resource (IWR) as follows, and the use of the IWR is determined
by the upper layer.
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ISO/IEC 4005-3:2023(E)
Four subchannels of frequency channel N_IWR, CCH , CCH , CCH , CCH
N_IWR,16 N_IWR,17 N_IWR,18 N_IWR,19
are designated as initial work channels. They are newly named IWRCH , IWRCH , IWRCH , IWRCH
0 1 2 3
respectively. These four initial work channels are not used for control, but are initially used to allocate
control subchannels (CSCHs) between the UA and the controller, where N_IWR is received from the
upper layer with UPtoDL.InfoIWRSlot.
The 25 slots of IWRCH are divided into five IWRs in order.
y
IR =ISRI, SR ,,,ISRISR ISR (3)
yi,,xi55xi, +15xi,,,+++25xi 35xi 4
where
y is an IWRCH number and has the value from 0 to 3;
ISR is i-th slot resource of IWRCH .
x,y,i y
5.1.6 Dedicated slots and dedicated subchannels
The upper layer can pre-determine one or more subchannels as dedicated subchannels. In this case,
the tone subslot sets mapped with the dedicated subchannel is not used as a competition tone and can
be used for other purposes. Slots in the dedicated subchannel are used as dedicated slots (DSs). One or
several dedicated slots can be assigned to UAs and controllers in advance. UAs and controllers use the
dedicated slots without competition.
It is recommended to set the dedicated subchannel in frequency channel N_IWR.
Dedicated subchannel information and dedicated slot information are received from an upper layer
through UPtoDL.InfoDedicatedChannel and UPtoDL.InfoDedicatedSlot.
5.2 Channel and frame structure for tone channel
5.2.1 Frame structure and bandwidth
The tone channel of the control communication indicates a competitive tone channel. The frame length
of tone channel is 1 sec and the number of slots per frame is 500. Four tone slots constitute one tone
slock block (TSB). Thus, there are 125 TSBs in one second frame as shown in Figure 5.

a
1 frame, T = 1 second = 500 T
f s.
b
1 slot, T = 2 ms.
s
c
1 slot block, T = 8 ms.
sb
Figure 5 — Frame structure of tone channel in control communication
The bandwidth of the tone channel is 250 kHz. FN is a frame number that varies from 0 to 59 and has
the same value as the second of the current time.
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ISO/IEC 4005-3:2023(E)
5.2.2 Slot transmit power
The maximum slot transmission power of the tone channel, PmaxTCH, is received as UPtoDL.
InfoPowerParamCCH from the upper layer. The transmission power of the tone subslot signal is
determined by adding the PTX_CCHTCH_differ value to the transmission power of the mapped CSCH.
5.2.3 Slot block structure
There are three types of slot blots. TSBtype0, TSBtype1, TSBtype2 are these. The type of each slot blot
of the TCH is received from the upper layer as UPtoDL.InfoTSBTypeMap.
There are 132 subslots in one slot block of TSBtype0. The length T of the subslot is 60 μs. The 132
ss
subslots are divided into four parts, as shown in Figure 6, according to each slot numbers.

a
Type 0.
b
1 slot block, T = 8 ms.
sb
c
T = 60 μs.
ss
d
40 μs.
Figure 6 — Type 0 TSB structure
In case of TSBtype0, n-th slot block is composed as follows.
— (0, 4n), (0, (4n + 1)), (0, (4n + 2)), (0, (4n + 3)), (1, 4n), (1, (4n + 1) ), (1, (4n + 2)), (1, (4n + 3)),. , (32,
4n), (32, (4n + 1)), (32, (4n + 2)), (32, (4n + 3))
where (x, y) is the x-th subslot of the y-th subslot set. The 132 subslots are divided into four subslot sets.
— {S } = {(0, 4n), (1, 4n), ., (32, 4n)}
4n
— {S } = {(0, (4n + 1)), (1, (4n + 1)), ., (32, (4n + 1))}
4n+1
— {S } = {(0, (4n + 2)), (1, (4n + 2)), ., (32, (4n + 2))}
4n+2
— {S } = {(0, (4n + 3)), (1, (4n + 3)), ., (32, (4n + 3))}
4n+3
where {S } is the x-th subslot set.
x
There are a total of 80 subslots in TSBtype1. The length T of the subslot is 100 μs. The 80 subslots are
ss
divided into four parts, as shown in Figure 7, according to each slot number.
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ISO/IEC 4005-3:2023(E)

a
Type1.
b
1 slot block, T = 8 ms.
sb
c
T = 100 μs.
ss
Figure 7 — Type 1 TSB structure
The n-th slot block that belongs to TSBtype1 is composed of the following subslot combinations.
— (0, 4n), (0, (4n + 1)), (0, (4n + 2)), (0, (4n + 3)), (1, 4n), (1, (4n + 1) ), (1, (4n + 2)), (1, (4n + 3)),. , (19,
4n), (19, (4n + 1)), (19, (4n + 2)), (19, (4n + 3))
The 80 subslots make up four subslot sets.
— {S } = {(0, 4n), (1, 4n), ., (19, 4n)}
4n
— {S } = {(0, (4n + 1)), (1, (4n + 1)), ., (19, (4n + 1))}
4n+1
— {S } = {(0, (4n + 2)), (1, (4n + 2)), ., (19, (4n + 2))}
4n+2
— {S } = {(0, (4n + 3)), (1, (4n + 3)), ., (19, (4n + 3))}
4n+3
There are a total of 40 subslots in TSBtype2. The length T of the subslot is 200 μs. The 40 subslots are
ss
divided into four parts, as shown in Figure 8, according to each slot numbers.

a
Type2.
b
1 slot block, T = 8 ms.
sb
c
T = 200 μs.
ss
Figure 8 — Type 2 TSB structure
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ISO/IEC 4005-3:2023(E)
The n-th slot block that belongs to TSBtype2 is composed of the following subslot combinations.
— (0, 4n), (0, (4n + 1)), (0, (4n + 2)), (0, (4n + 3)), (1, 4n), (1, (4n + 1) ), (1, (4n + 2)), (1, (4n + 3)),. , (9, 4n),
(9, (4n + 1)), (9, (4n + 2)), (9, (4n + 3))
The 40 subslots make up four subslot sets.
— {S } = {(0, 4n), (1, 4n), ., (9, 4n)}
4n
— {S } = {(0, (4n + 1)), (1, (4n + 1)), ., (9, (4n + 1))}
4n+1
— {S } = {(0, (4n + 2)), (1, (4n + 2)), ., (9, (4n + 2))}
4n+2
— {S } = {(0, (4n + 3)), (1, (4n + 3)), ., (9, (4n + 3))}
4n+3
Regardless of the typ
...

Deleted: ¶
ISO/IEC FDIS 4005-3
ISO/IEC JTC 1/SC 6
Date: 2022-12-02
Telecommunications and information exchange between
Deleted: -
systems — Unmanned aircraft area network (UAAN) —
Deleted:
Part 3:
Deleted:
Physical and data link protocols for control communication
Télécommunications et échange d'information entre systèmes — Réseau de zone de drones (Unmanned
Deleted: ¶
Page Break
aircraft area network - UAAN) —
¶
ISO/IEC DIS 4005-3:2022(X)¶
Partie 3: Protocoles de liaison de données et physiques pour la communication de contrôle
ISO/IEC JTC 1/SC 6/WG 1¶
Secretariat: KATS¶
Telecommunications and information exchange
between systems —
Deleted: (UAAN) — Part 3: Physical and data link
protocols for control communication
Deleted: ¶
FDIS stage
Deleted: ¶
Warning for DISs¶
This document is not an ISO International Standard. It is
distributed for review and comment. It is subject to
change without notice and may not be referred to as an
International Standard.¶
Recipients of this draft are invited to submit, with their
comments, notification of any relevant patent rights of
which they are aware and to provide supporting
documentation.¶
¶
© ISO 20XX¶
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ISO/IEC FDIS 4005-3:2022(E)
Deleted:
© ISO/IEC 2022 Deleted: DIS
Deleted: 2021(X
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this
publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical,
including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can
be requested from either ISO at the address below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: + 41 22 749 01 11
E-mail: [e-mail]
Deleted: Fax: [phone]¶
Website: www.iso.org
Email
Deleted: www.iso.org
Published in Switzerland
Deleted: ####
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ISO/IEC FDIS 4005-3:2022(E)
Deleted:

Deleted: DIS
Deleted: 2021(X

Deleted: ¶
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ISO/IEC FDIS 4005-3:2022(E)
Deleted:
Foreword
Deleted: DIS
Deleted: 2021(X
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are
members of ISO or IEC participate in the development of International Standards through technical
committees established by the respective organization to deal with particular fields of technical activity.
ISO and IEC technical committees collaborate in fields of mutual interest. Other international
organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the
work.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of document should be noted. This document was drafted in accordance with the editorial
rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives or Deleted: www.iso.org/directives or
www.iec.ch/members_experts/refdocs
www.iec.ch/members_experts/refdocs).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights. Details
of any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents) or the IEC list of patent Deleted: www.iso.org/patents
declarations received (see https://patents.iec.ch).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the World
Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see
www.iso.org/iso/foreword.html. In the IEC, see www.iec.ch/understanding-standards.
Deleted: www.iso.org/iso/foreword.html. In the IEC, see
www.iec.ch/understanding-standards
This document was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 6, Telecommunications and information exchange between systems.
A list of all parts in the ISO/IEC 4005 series can be found on the ISO and IEC websites.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html and www.iec.ch/national-
Deleted: www.iso.org/members.html
committees.
Field Code Changed
Deleted: ####
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ISO/IEC FDIS 4005-3:2022(E)
Deleted:
Introduction
Deleted: DIS
Deleted: 2021(X
Unmanned aircraft (UAs) operating at low altitudes will provide a variety of commercial services in the
near future. UAs that provide these services are distributed in the airspace. In low uncontrolled airspace,
many people operate their own UAs without the assignment of communication channels from a central
control centre. Deleted: center.
This document describes control communication, which is a wireless distributed communication. Control
communication allows control pairs of UA and controller distributed over the airspace to communicate
with each other without serious interference. The channel used for control communication has a multi-
channel structure, which enables UAs and controllers to independently use the communication link
occupied by each other. A wireless distributed communication described by this document is intended to
be used in licensed frequency bands.
The ISO/IEC 4005 series consists of the following four parts:
Deleted: ISO/IEC 4005-1: To support various
ISO/IEC 4005-1: To support various services for UAs, it describes a wireless distributed
services for UAs, it describes a wireless distributed
communication model and the requirements that this model shall satisfy.
communication model and the requirements that
this model shall satisfy.¶
ISO/IEC 4005-2: It describes communication in which all units involved in UA operation can
ISO/IEC 4005-2: It describes communication in
broadcast or exchange information by sharing communication resources with each
which all units involved in UA operation can
other.
broadcast or exchange information by sharing
communication resources with each other.¶
ISO/IEC 4005-3 (this document): It describes the control communication for the controller to
ISO/IEC 4005-3 (this document) : It describes the
control the UA.
control communication for the controller to control
the UA.¶
ISO/IEC 4005-4: It describes video communication for UAs to send video to a controller.
ISO/IEC 4005-4: It describes video communication
The International Organization for Standardization (ISO) and International Electrotechnical Commission
for UAs to send video to a controller.¶
(IEC) draw attention to the fact that it is claimed that compliance with this document may involve the use
of patents. Deleted:
ISO and IEC take no position concerning the evidence, validity and scope of these patent rights. Deleted:
The holders of these patent rights have assured ISO and IEC that they are willing to negotiate licences
under reasonable and non-discriminatory terms and conditions with applicants throughout the world. In
this respect, the statements of the holders of these patent rights are registered with ISO and IEC.
Information may be obtained from the patent database available at www.iso.org/patents. Deleted: www.iso.org/patents.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights other than those in the patent database. ISO and IEC shall not be held responsible for
identifying any or all such patent rights.
Deleted: ¶
Deleted: ####
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ISO/IEC FDIS 4005-3:2022(E)
Telecommunications and information exchange between
Deleted:
systems — Unmanned aircraft area network (UAAN) —
Deleted: —
Deleted:
Part 3:
Deleted:
Physical and data link protocols for control communication
1 Scope
This document specifies communication protocols for the physical and data link layer for control
communication, which is wireless distributed communication network for level II unit-related unmanned Deleted: units
aircraft (UAs).
Deleted: with
This document describes control communication, which is one-to-one communication between a UA and Deleted: in level II.
a controller.
Deleted:
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.
ISO/IEC 4005-1, Telecommunications and information exchange between systems — Unmanned aircraft
Deleted: ISO 21384-4: Unmanned aircraft systems — Part
4: UAS vocabulary¶
area network (UAAN) — Part 1: Communication model and requirements
Deleted:
ISO/IEC 4005-2:20—, Telecommunications and information exchange between systems — Unmanned
Deleted:
aircraft area network (UAAN) — Part 2: Physical and data link protocols for shared communication
Deleted:
ISO/IEC 4005-4, Telecommunications and information exchange between systems — Unmanned aircraft Deleted: :
area network (UAAN) — Part 4: Physical and data link protocols for video communication
Deleted: —
Deleted: https://www.iso.org/obp
ISO 21384-4, Unmanned aircraft systems — Part 4: Vocabulary
Deleted: —
3 Terms and definitions
Deleted: https://www.electropedia.org/
Deleted: ¶
For the purposes of this document, the terms and definitions defined in ISO/IEC 4005-1, ISO/IEC 4005-
Deleted:
2, ISO 21384-4 and the following apply.
Deleted:
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
Deleted:
— ISO Online browsing platform: available at https://www.iso.org/obp
Deleted:
— IEC Electropedia: available at https://www.electropedia.org/ Deleted: ¶
Deleted: CC Control Communication¶
3.1
CRC Cyclic Redundancy Check¶
subchannel map
CSCH Control Subchannel¶
DLL Data Link Layer¶
2-bit string indicating whether subchannels are available
DS Dedicated Slot¶
FN Frame Number¶
Note 1 to entry: In wireless distributed communication, the subchannel map of each unit is generally different.
IWR Initial Work Resource¶
LFSR Linear Feedback Shift Register¶
4 Abbreviated terms PB Parsing Block¶
PKH Packet Header¶
PN Pseudo Noise¶
CC Control Communication
SA Source Address¶
SC Shared Communication¶
CRC Cyclic Redundancy Check
TSB Tone Slot Block¶
TX Transmission¶
CSCH Control Subchannel
UTC Coordinated Universal Time¶
DLL Data Link Layer VC Video Communication¶
VSCH Video Subchannel¶
DS Dedicated Slot
¶
Deleted: ####
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ISO/IEC FDIS 4005-3:2022(E)
FN Frame Number
IWR Initial Work Resource
LFSR Linear Feedback Shift Register
PB Parsing Block
PKH Packet Header
PN Pseudo Noise
SA Source Address
SC Shared Communication
TSB Tone Slot Block
TX Transmission
UTC Coordinated Universal Time
VC Video Communication
VSCH Video Subchannel
5 Physical layer
5.1 Channel and frame structure for data channel
Deleted: The number
5.1.1 Number of data channels and bandwidth
Deleted: Figure 1.
The number of data channels is N as shown in Figure 1. N is greater than or equal to one. The bandwidth
Deleted: .
of one data channel is 1,25 MHz. The N is determined in the upper layer.
Deleted:
1.25MHz 1.25MHz
(#0) (#1)

Figure 1 — Data channels in frequency region
Deleted:
Deleted: 1
5.1.2 Frame structure
Deleted: ¶
The frame length of the data channel is 1 sec and consists of 500 slots and one slot time Ts is 2 ms as Deleted: second
shown in Figure 2. FN is a frame number that varies from 0 to 59 and has the same value as the second of
Deleted:
the current time.
Deleted: Figure 2.
Deleted: ,
Deleted:
a
#0 #1 #2 #3


a
1 frame, T = 1 sec = 500 T
f s.
b
b
1 slot, Ts = 2 ms. Deleted:
Key¶
a
1 frame, Tf = 1 second = 500 Ts¶
Figure 2 — Frame structure of the control channel b
1 slot, T = 2 ms¶
s
Deleted: 2
Deleted: ####
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ISO/IEC FDIS 4005-3:2022(E)
5.1.3 Slot transmit time mask
Deleted: ¶
The transmission time mask of a slot is shown in Figure 3. Deleted: Figure 3.
a
b


T T
0 1
Deleted:
a
2 ms.
Key¶
a
b
2 ms¶
Modulated signal.
b
modulated signal¶
Figure 3 — The transmission time mask of a slot
Deleted: 3
T , T , T , T are symbol offsets from T and symbol time is 1/672000 sec. Each value is as follows: T is 2,
1 2 3 4 0 1 Deleted: Where
T2 is 1297, T3 is 1299, T4 is 1344.
Deleted: second
T0 is 0 μs as the start time of the slot and the power amplifier is gated on and unmodulated fine signals
Deleted: .
begin to be transmitted. T is an offset at which modulation signal transmission starts. T is an offset at
1 2
Deleted: Where,
which the transmission of the modulated signal ends. T3 is an offset at which the power amplifier is gated
Deleted:
off, and transmission of unmodulated fine signals is stopped. The transmit power of T to T , T to T shall
0 1 2 3
be at least 50 dB less than the modulation signal transmit power.
5.1.4 Subchannels
Deleted: ¶
5.1.4.1 General
One data channel consists of 20 subchannels as shown in Figure 4. Subchannel y of control channel x is Deleted: Figure 4.
composed of the following slot set.
CCHx,y = Sx,z, Sx,z+20, Sx,z+40, …, Sx,z+480 Deleted:
𝑦𝑦,   𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒
y, evenframe
𝑧𝑧  =    (1)
Deleted: z=
𝑦𝑦 + 2−⌊(𝑦𝑦 mod 4)/2⌋  ×  4, 𝑜𝑜𝑜𝑜𝑜𝑜𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒
y+−2 (y mod4) / 2 × 4, oddfram

(1)¶
where
 y is subchannel number, y=0, 1, …, 19;
Deleted: ,
 S is slot z of control channel x. Deleted: ;
x,z

Deleted: ¶
...
Deleted: ####
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ISO/IEC FDIS 4005-3:2022(E)


a
CCHx
b
CCH
x,0
c
CCHx,1
d
CCH
x,18
e
CCHx,19
Figure 4 — Subchannel structure of control communication in even frame Deleted: 4—
A subchannel consists of 25 slots, the i-th slot resource of the subchannel y of the channel x is indicated
Deleted: ¶
by SR and the subchannel y of frequency channel x is indicated by CCH . Therefore, CCH is as follows.
x,y,i x,y x,y
Deleted:
𝐶𝐶𝐶𝐶𝐻𝐻 =𝑆𝑆𝑅𝑅 ,𝑆𝑆𝑅𝑅 , … ,𝑆𝑆𝑅𝑅 (2)
𝑥𝑥,𝑦𝑦 𝑥𝑥,𝑦𝑦 ,0 𝑥𝑥,𝑦𝑦 ,1 𝑥𝑥,𝑦𝑦 ,24 Deleted: ,
Deleted: CCH = SR , SR , …, SR (2)¶
x,y x,y,0 x,y,1 x,y,24
where SR is i-th slot resource of subchannel y of channel x, i=0, …, 24.
x,y,i
where¶
...
5.1.4.2 Up and down link decision of slot resources
For SR , 5 slots satisfying (i mod 5) =(FN mod 5) are downlink and remain 20 slots are uplink, where Deleted: ,
x,y,i
mod means modulo operation.
Deleted: . Where
5.1.5 Initial work resources (IWR) and channel
The upper layer can set the initial work resource (IWR) as follows, and the use of the IWR is determined Deleted: ,
by the upper layer.
Deleted: ,
Four subchannels of frequency channel N_IWR, CCH , CCH , CCH , CCH are
N_IWR,16 N_IWR,17 N_IWR,18 N_IWR,19 Deleted: initial work resource
designated as initial work channels. They are newly named IWRCH , IWRCH , IWRCH , IWRCH
0 1 2 3
respectively. These four initial work channels are not used for control, but are initially used to allocate
control subchannels (CSCHs) between the UA and the controller, where N_IWR is received from the upper Deleted: . Where,
layer with UPtoDL.InfoIWRSlot.
The 25 slots of IWRCH are divided into five IWRs in order.
y Deleted: 5 initial work resources
𝐼𝐼𝑅𝑅 =𝐼𝐼𝑆𝑆𝑅𝑅 ,𝐼𝐼𝑆𝑆𝑅𝑅 ,𝐼𝐼𝑆𝑆𝑅𝑅 ,𝐼𝐼𝑆𝑆𝑅𝑅 ,𝐼𝐼𝑆𝑆𝑅𝑅 (3)
Deleted: IR = ISR , ISR , ISR , ISR ,
𝑦𝑦,𝑖𝑖 𝑥𝑥,5𝑖𝑖 𝑥𝑥,5𝑖𝑖 +1 𝑥𝑥,5𝑖𝑖 +2 𝑥𝑥,5𝑖𝑖 +3 𝑥𝑥,5𝑖𝑖 +4 y,i x,5i x,5i+1 x,5i+2 x,5i+3
ISRx,5i+4 (3)¶
where
Deleted: ####
4 © ISO/IEC 2022 – All rights reserved

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ISO/IEC FDIS 4005-3:2022(E)
 y is an IWRCH number and has the value from 0 to 3; Deleted: ,
 ISR is i-th slot resource of IWRCH . Deleted: ;
x,y,i y
5.1.6 Dedicated slots and dedicated subchannels
The upper layer can pre-determine one or more subchannels as dedicated subchannels. In this case, the
tone subslot sets mapped with the dedicated subchannel is not used as a competition tone and can be Deleted: ,
used for other purposes. Slots in the dedicated subchannel are used as dedicated slots (DSs). One or
several dedicated slots can be assigned to UAs and controllers in advance. UAs and controllers use the
dedicated slots without competition.
It is recommended to set the dedicated subchannel in frequency channel N_IWR. Deleted:
Dedicated subchannel information and dedicated slot information are received from an upper layer
through UPtoDL.InfoDedicatedChannel and UPtoDL.InfoDedicatedSlot.
5.2 Channel and frame structure for tone channel
5.2.1 Frame structure and bandwidth
The tone channel of the control communication indicates a competitive tone channel. The frame length
of tone channel is 1 sec and the number of slots per frame is 500. Four tone slots constitute one tone slock
Deleted: second
block (TSB). Thus, there are 125 TSBs in one second frame as shown in Figure 5.
Deleted: ,
Deleted: .
Deleted: Figure 5.
Deleted:
a
b


#0 #1 #2 #3 #4 #5 #6 #7
a
1 frame, T = 1 second = 500 T
f s.
b
1 slot, Ts = 2 ms.
c
1 slot block, T = 8 ms.
sb
c
Key¶
Figure 5 — Frame structure of tone channel in control communication a
1 frame, T = 1 second = 500 T ¶
f s
b
1 slot, T = 2 ms¶
s
c
1 slot block, Tsb = 8 ms¶
The bandwidth of the tone channel is 250 kHz. FN is a frame number that varies from 0 to 59 and has the
Deleted: 5
same value as the second of the current time.
Deleted:
5.2.2 Slot transmit power
Deleted: ,
The maximum slot transmission power of the tone channel, PmaxTCH, is received as
UPtoDL.InfoPowerParamCCH from the upper layer. The transmission power of the tone subslot signal is
determined by adding the PTX_CCHTCH_differ value to the transmission power of the mapped CSCH.
Deleted: control subchannel
5.2.3 Slot block structure
There are three types of slot blots. TSBtype0, TSBtype1, TSBtype2 are these. The type of each slot blot of
the TCH is received from the upper layer as UPtoDL.InfoTSBTypeMap.
There are 132 subslots in one slot block of TSBtype0. The length T of the subslot is 60 μs. The 132 Deleted:
ss
subslots are divided into four parts, as shown in Figure 6, according to each slot numbers.
Deleted: Figure 6
Deleted:
Deleted: ####
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ISO/IEC FDIS 4005-3:2022(E)
Deleted:
a
b
(0,0) (0,1) (0,2) (0,3) (1,0) (1,1) (1,2) (1,3) (16,3)

 c
a
Type 0. Key¶
a
b type0¶
1 slot block, Tsb = 8 ms.
b
1 slot block, T = 8 ms¶
sb
c
T = 60 μs.
ss
c
Tss = 60 μs¶
d d
40 μs. 40 μs¶
Figure 6 — Type 0 TSB structure
Deleted: 6
In case of TSBtype0, n-th slot block is composed as follows.
— (0, 4n), (0, (4n + 1)), (0, (4n + 2)), (0, (4n + 3)), (1, 4n), (1, (4n + 1) ), (1, (4n + 2)), (1, (4n + 3)),. , (32,
4n), (32, (4n + 1)), (32, (4n + 2)), (32, (4n + 3))
where (x, y) is the x-th subslot of the y-th subslot set. The 132 subslots are divided into four subslot sets. Deleted: ,
Deleted: 4
— {S } = {(0, 4n), (1, 4n), ., (32, 4n)}
4n
Deleted:
— {S } = {(0, (4n + 1)), (1, (4n + 1)), ., (32, (4n + 1))}
4n+1
Deleted:
— {S4n+2} = {(0, (4n + 2)), (1, (4n + 2)), ., (32, (4n + 2))}
— {S } = {(0, (4n + 3)), (1, (4n + 3)), ., (32, (4n + 3))}
4n+3
Deleted: ,
where {S } is the x-th subslot set.
x
Deleted:
There are a total of 80 subslots in TSBtype1. The length T of the subslot is 100 μs. The 80 subslots are
ss
Deleted: Figure 7
divided into four parts, as shown in Figure 7, according to each slot number.
Deleted: numbers.
Deleted:
a
b

(0,0) (0,1) (0,2) (0,3) (1,0) (1,1) (1,2) (1,3)

a
Type1.
c
b
1 slot block, T = 8 ms.
sb
Key¶
c
Tss = 100 μs.
a
type1¶
b
1 slot block, Tsb = 8 ms¶
c
T = 100 μs¶
ss
Figure 7 — Type 1 TSB structure
Deleted: 7
Deleted: ####
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ISO/IEC FDIS 4005-3:2022(E)
The n-th slot block that belongs to TSBtype1 is composed of the following subslot combinations.
— (0, 4n), (0, (4n + 1)), (0, (4n + 2)), (0, (4n + 3)), (1, 4n), (1, (4n + 1) ), (1, (4n + 2)), (1, (4n + 3)),. , (19,
4n), (19, (4n + 1)), (19, (4n + 2)), (19, (4n + 3))
Deleted:
The 80 subslots make up four subslot sets. Deleted: 4
— {S4n} = {(0, 4n), (1, 4n), ., (19, 4n)} Deleted:
— {S } = {(0, (4n + 1)), (1, (4n + 1)), ., (19, (4n + 1))} Deleted:
4n+1
— {S } = {(0, (4n + 2)), (1, (4n + 2)), ., (19, (4n + 2))}
4n+2
— {S4n+3} = {(0, (4n + 3)), (1, (4n + 3)), ., (19, (4n + 3))}
Deleted: {S }
4n + 3
There are a total of 40 subslots in TSBtype2. The length T of the subslot is 200 μs. The 40 subslots are Deleted:
ss
divided into four parts, as shown in Figure 8, according to each slot numbers.
Deleted: Figure 8
Deleted:
Deleted:
a
b

(0,0) (0,1) (0,2) (0,3) (1,0) (1,1) (1,2) (1,3)

a
Type2.
b c
1 slot block, T = 8 ms.
sb
c
Tss = 200 μs. Key¶
a
type2¶
b
1 slot block, T = 8 ms¶
sb
Figure 8 — Type 2 TSB structure
c
Tss = 200 μs¶
Deleted: 8
The n-th slot block that belongs to TSBtype2 is composed of the following subslot combinations.
Deleted: n
— (0, 4n), (0, (4n + 1)), (0, (4n + 2)), (0, (4n + 3)), (1, 4n), (1, (4n + 1) ), (1, (4n + 2)), (1, (4n + 3)),. , (9,
4n), (9, (4n + 1)), (9, (4n + 2)), (9, (4n + 3))
The 40 subslots make up four subslot sets. Deleted: 4
— {S4n} = {(0, 4n), (1, 4n), ., (9, 4n)} Deleted:
— {S } = {(0, (4n + 1)), (1, (4n + 1)), ., (9, (4n + 1))} Deleted:
4n+1
— {S } = {(0, (4n + 2)), (1, (4n + 2)), ., (9, (4n + 2))}
4n+2
— {S4n+3} = {(0, (4n + 3)), (1, (4n + 3)), ., (9, (4n + 3))}
Deleted: {S }
4n + 3
Regardless of the type of TSB, there are a total of 500 subslot sets in one frame. Deleted: tone slot block
5.2.4 Subslot transmission time mask
Subslot transmission time mask is shown in Figure 9.
Deleted: Figure 9.
Deleted: ####
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ISO/IEC FDIS 4005-3:2022(E)
Deleted:
a
1 μs 40 μs

c
Key
T 0 μs
0
T1, T2, T3, T4 time offsets from T0 T T
0 1
a
Subslot start.
Deleted: T 0 μs¶
0
b
Subslot end.
T , T , T , T time offsets from T ¶
1 2 3 4 0
c a
Tone signal. subslot start¶
b
subslot end¶
d
Guard time.
c
tone signal¶
d
guard time¶
Figure 9 — Subslot transmission time mask
Deleted: 9
T , T , T , and T are time offsets from T . T is 1 μs, T is 41 μs, and T is 42 μs.
1 2 3 4 0 1 2 3 Deleted: Where,
Deleted:
In TSBtype0, T is 60 μs, guard time is 18 μs.
4
Deleted:
In TSBtype1, T4 is 100 μs, guard time is 58 μs.
Deleted:
In TSBtype2, T4 is 200 μs, guard time is 158 μs.
Deleted:
T0 is the time when the power amplifier is gated on, and unmodulated fine signals begin to be transmitted.
Deleted:
T is the time at which transmission of the modulated signal begins. T is the time at which transmission
1 2
Deleted:
of the modulated signal is terminated. T3 is the time when the power amplifier is gated off and the
transmission of unmodulated fine signals is stopped. The transmission power of the time region from T Deleted:
0
to T1 and the transmission power of the time region from T2 to T3 shall be 50dB or more less than the
modulated signal transmission power.
5.2.5 Subslot signal waveform
The subslot signal waveform is the same as that of shared communication. See ISO/IEC 4005-2:20—,
Deleted: of
5.1.2.3.
The modulation scheme of subslot signal is on-off keying. The subslot signal is started at T1 and Deleted: ,
transmitted during the 40 μs interval. The waveform of the subslot transmission signal uses a raised
Deleted:
cosine function. The subslot signal is generated by the following formula.
Deleted: equation
cos(𝜋𝜋𝜋𝜋(𝑡𝑡−2𝑇𝑇)) (𝑡𝑡−2𝑇𝑇)
𝑔𝑔(𝑡𝑡;𝛼𝛼) = sin𝑐𝑐( ), 0≤𝑡𝑡≤ 4𝑇𝑇 (4)
2
cosπα(t− 2T )
1−(2𝜋𝜋(𝑡𝑡−2𝑇𝑇)/𝑇𝑇) 𝑇𝑇 ( )
 (t− 2)T
Deleted: gt( ;α)= sinc

2
T
1−−(2α(t 2TT) / ) 
where
(4) ¶
 α is 0,75 as a roll-off factor;
 T is 10 μs as a raised cosine period. Deleted:
5.3 Encoding procedure
The encoding procedure is identical with that of shared communication. See ISO/IEC 4005-2:20—, 5.2.
The final encoded signal is located between T1 and T2 in Figure 3, i.e. in the modulated signal part. Deleted: Figure 3, i.e.
5.4 Physical layer procedure
5.4.1 Synchronization
All messages shall be transmitted based on UTC absolute time. All times are measured on UTC. Deleted:
The synchronization mode of the unit includes 'A sync', 'B sync' and 'C sync'.
— A sync is synchronization obtained from UTC.
Deleted: ####
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ISO/IEC FDIS 4005-3:2022(E)
— B sync is secondary synchronization acquired from the synchronization signal of the A sync unit.
— C sync is sync status within 20 sec after sudden loss of sync in A or B sync mode.
Deleted: seconds
A sync unit shall know the date, hour, minute, second, slot number.
The time error of A sync shall be within ±0,4 μs. The time error of B sync shall be within ±4 μs. The time Deleted: 4μs
error of C sync shall be within ±5 μs.
Deleted: 4μs
The frequency error of A sync shall be within ±0,1 ppm. The frequency error of the B sync shall be within Deleted: 5μs
±0,2 ppm. The frequency error of the C sync shall be within ±0,3 ppm.
Deleted: 1ppm
5.4.2 Subchannel power
Deleted: 2ppm
Deleted: 3ppm
The maximum power of the CSCH, PmaxCCH, is received as UPtoDL.InfoPowerParamCCH from the upper
Deleted: control subchannel
layer. The maximum transmission power and minimum transmission power of each CSCH are received
from the upper layer as UPtoDL.InfoPowerParamCCHsub. The power control of each CSCH is described Deleted: control subchannel
in the resource allocation procedure.
Deleted: control subchannel
5.4.3 Measurements
The physical layer shall have the ability to measure the following parameters. The received signal power
of a tone subslot, the received signal power of a data slot, and propagation delay time of the received data
signal shall be measured. The receiving power determination point shall be the receiving antenna
connector.
5.4.4 Coexistence operation
Deleted: Operation
If the hardware of shared communication described in ISO/IEC 4005-2 and the hardware of control
communication described in this document and the hardware of video communication described in
ISO/IEC 4005-4 are completely physically isolated and do not affect each other at all, it shall be allowed
that they do not perform coexistence operations, which is implementation dependent. In general, the
three communications affect each other, and in this case, the following coexistence operations shall be
performed.
The TX operation of a shared slot includes the TX of the corresponding shared slot and the TX operation
in the mapped tone subslot set. The TX operation of a control communication includes TX of the mapped
tone subslot set and CSCH TX. The TX operation of video communication includes TX of a mapped tone
subslot set and VSCH TX.
When a UA periodically broadcasts its information to a shared slot of a shared channel, a shared slot and
a tone subslot set mapped to the shared slot generally require 1 slot and 4 slots, respectively, for TX
operation. If the TX operation of the shared slot used for mandatory periodic broadcasting and the TX
operation of the control channel overlap, the TX operation of the shared slot shall be performed.
A CSCH and a VSCH shall be allocated so that they do not overlap in time.
Deleted: control subchannel
Deleted: video subchannel
The TX time of the tone subslot set mapped with mandatory periodically broadcasted shared slot, the TX
time of the tone subslot set mapped with the CSCH, and the TX time of the tone subslot set mapped with
the VSCH shall not overlap each other. If the control TSB type is TSBtype0, the control tone subslot set
Deleted: tone slot block
and the shared tone subslot set can be located in the same TSB. In this case, the two tone subslot set
Deleted: tone slot block.
numbers shall be different. If the control TSB type is not TSBtype0, the control tone subslot set and the
Deleted: tone slot block
shared tone subslot set cannot be located in the same TSB.
Deleted: tone slot block
The TX operation time of the tone subslot set mapped with a CSCH can overlap the TX time of a VSCH, and
Deleted: control subchannel
in this case, the corresponding video slot cannot be transmitted. The TX operation time of the tone subslot
Deleted: video subchannel
set mapped with a VSCH can overlap with the slot TX time of a CSCH, and in this case, the corresponding
control slot cannot be transmitted. Deleted: video subchannel
Deleted: control subchannel
The coexistence operation of the tone subslot set
...

FINAL
INTERNATIONAL ISO/IEC
DRAFT
STANDARD FDIS
4005-3
ISO/IEC JTC 1/SC 6
Telecommunications and information
Secretariat: KATS
exchange between systems —
Voting begins on:
2022-12-19 Unmanned aircraft area network
(UAAN) —
Voting terminates on:
2023-02-13
Part 3:
Physical and data link protocols for
control communication
Télécommunications et échange d'information entre systèmes —
Réseau de zone de drones (Unmanned aircraft area network -
UAAN) —
Partie 3: Protocoles de liaison de données et physiques pour la
communication de contrôle
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/IEC FDIS 4005-3:2022(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. © ISO/IEC 2022

---------------------- Page: 1 ----------------------
ISO/IEC FDIS 4005-3:2022(E)
FINAL
INTERNATIONAL ISO/IEC
DRAFT
STANDARD FDIS
4005-3
ISO/IEC JTC 1/SC 6
Telecommunications and information
Secretariat: KATS
exchange between systems —
Voting begins on:
Unmanned aircraft area network
(UAAN) —
Voting terminates on:
Part 3:
Physical and data link protocols for
control communication
Télécommunications et échange d'information entre systèmes —
Réseau de zone de drones (Unmanned aircraft area network -
UAAN) —
Partie 3: Protocoles de liaison de données et physiques pour la
communication de contrôle
COPYRIGHT PROTECTED DOCUMENT
© ISO/IEC 2022
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
RECIPIENTS OF THIS DRAFT ARE INVITED TO
ISO copyright office
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
CP 401 • Ch. de Blandonnet 8
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
CH-1214 Vernier, Geneva
DOCUMENTATION.
Phone: [phone]
IN ADDITION TO THEIR EVALUATION AS
Reference number
Email: [e-mail]
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­
ISO/IEC FDIS 4005­3:2022(E)
Website: www.iso.org
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
Published in Switzerland
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN­
DARDS TO WHICH REFERENCE MAY BE MADE IN
ii
  © ISO/IEC 2022 – All rights reserved
NATIONAL REGULATIONS. © ISO/IEC 2022

---------------------- Page: 2 ----------------------
ISO/IEC FDIS 4005-3:2022(E)
Contents Page
Foreword .v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 1
5 Physical layer . 2
5.1 Channel and frame structure for data channel . 2
5.1.1 Number of data channels and bandwidth . 2
5.1.2 Frame structure . 2
5.1.3 Slot transmit time mask . . 3
5.1.4 Subchannels . 3
5.1.5 Initial work resources (IWR) and channel . 4
5.1.6 Dedicated slots and dedicated subchannels . 5
5.2 Channel and frame structure for tone channel . 5
5.2.1 Frame structure and bandwidth . 5
5.2.2 Slot transmit power . 6
5.2.3 Slot block structure . 6
5.2.4 Subslot transmission time mask . 8
5.2.5 Subslot signal waveform. 8
5.3 Encoding procedure . 9
5.4 Physical layer procedure . 9
5.4.1 Synchronization . 9
5.4.2 Subchannel power . 9
5.4.3 Measurements . 9
5.4.4 Coexistence operation . 9
6 Data link layer .10
6.1 General . 10
6.2 Channel mapping and measurements.12
6.2.1 General .12
6.2.2 Mapping of communication resources and subslot sets.12
6.2.3 Interference power calculation . 13
6.2.4 Subchannel map . 14
6.3 Subchannel negotiation for allocation . 14
6.3.1 General . 14
6.3.2 Subchannel negotiation using shared channel . 19
6.3.3 Subchannel negotiation using dedicated slot . 21
6.3.4 Subchannel negotiation using IWR . 23
6.4 Resource allocation competition and generated link confirmation . 26
6.4.1 General . 26
6.4.2 Subchannel resource allocation competition . 27
6.4.3 Generated link confirmation .29
6.4.4 Broadcasting control channel information being allocated or occupied . 31
6.5 Subchannel occupation and collision management . 32
6.5.1 General . 32
6.5.2 Subchannel occupation and return . 32
6.5.3 Collision tone transmission and collision management . 32
6.5.4 Power control in occupation stage .34
6.6 Reallocation . . 35
6.6.1 General . 35
6.6.2 Reallocation decision . 35
6.6.3 Subchannel reallocation procedure .38
iii
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ISO/IEC FDIS 4005-3:2022(E)
6.7 Data exchange . 39
6.7.1 General .39
6.7.2 Data packet format . 39
6.8 Synchronization . 43
6.9 Data link layer security . 43
6.10 Interface with upper layers . 45
6.10.1 General . 45
6.10.2 Initialization interface. 45
6.10.3 Dynamic interface . 51
6.11 Interface with other communication layer . 55
6.11.1 General . 55
6.11.2 Interface with SC . 55
6.11.3 Interface with VC . .56
Bibliography .59
iv
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ISO/IEC FDIS 4005-3:2022(E)
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are
members of ISO or IEC participate in the development of International Standards through technical
committees established by the respective organization to deal with particular fields of technical
activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other international
organizations, governmental and non­governmental, in liaison with ISO and IEC, also take part in the
work.
The procedures used to develop this document and those intended for its further maintenance
are described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria
needed for the different types of document should be noted. This document was drafted in
accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives or
www.iec.ch/members_experts/refdocs).
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent
rights. Details of any patent rights identified during the development of the document will be in the
Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents) or the IEC
list of patent declarations received (see https://patents.iec.ch).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see
www.iso.org/iso/foreword.html. In the IEC, see www.iec.ch/understanding­standards.
This document was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 6, Telecommunications and information exchange between systems.
A list of all parts in the ISO/IEC 4005 series can be found on the ISO and IEC websites.
Any feedback or questions on this document should be directed to the user’s national standards
body. A complete listing of these bodies can be found at www.iso.org/members.html and
www.iec.ch/national­committees.
v
© ISO/IEC 2022 – All rights reserved

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ISO/IEC FDIS 4005-3:2022(E)
Introduction
Unmanned aircraft (UAs) operating at low altitudes will provide a variety of commercial services in
the near future. UAs that provide these services are distributed in the airspace. In low uncontrolled
airspace, many people operate their own UAs without the assignment of communication channels from
a central control centre.
This document describes control communication, which is a wireless distributed communication. Control
communication allows control pairs of UA and controller distributed over the airspace to communicate
with each other without serious interference. The channel used for control communication has a multi­
channel structure, which enables UAs and controllers to independently use the communication link
occupied by each other. A wireless distributed communication described by this document is intended
to be used in licensed frequency bands.
The ISO/IEC 4005 series consists of the following four parts:
ISO/IEC 4005­1: To support various services for UAs, it describes a wireless distributed communica­
tion model and the requirements that this model shall satisfy.
ISO/IEC 4005­2: It describes communication in which all units involved in UA operation can broad­
cast or exchange information by sharing communication resources with each other.
ISO/IEC 4005­3 (this document): It describes the control communication for the controller to con­
trol the UA.
ISO/IEC 4005­4: It describes video communication for UAs to send video to a controller.
The International Organization for Standardization (ISO) and International Electrotechnical
Commission (IEC) draw attention to the fact that it is claimed that compliance with this document may
involve the use of patents.
ISO and IEC take no position concerning the evidence, validity and scope of these patent rights.
The holders of these patent rights have assured ISO and IEC that they are willing to negotiate licences
under reasonable and non-discriminatory terms and conditions with applicants throughout the world.
In this respect, the statements of the holders of these patent rights are registered with ISO and IEC.
Information may be obtained from the patent database available at www.iso.org/patents.
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights other than those in the patent database. ISO and IEC shall not be held responsible for
identifying any or all such patent rights.
vi
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FINAL DRAFT INTERNATIONAL STANDARD ISO/IEC FDIS 4005-3:2022(E)
Telecommunications and information exchange between
systems — Unmanned aircraft area network (UAAN) —
Part 3:
Physical and data link protocols for control communication
1 Scope
This document specifies communication protocols for the physical and data link layer for control
communication, which is wireless distributed communication network for level II unit­related
unmanned aircraft (UAs).
This document describes control communication, which is one­to­one communication between a UA
and a controller.
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.
ISO/IEC 4005­1, Telecommunications and information exchange between systems — Unmanned aircraft
area network (UAAN) — Part 1: Communication model and requirements
ISO/IEC 4005­2:20—, Telecommunications and information exchange between systems — Unmanned
aircraft area network (UAAN) — Part 2: Physical and data link protocols for shared communication
ISO/IEC 4005­4, Telecommunications and information exchange between systems — Unmanned aircraft
area network (UAAN) — Part 4: Physical and data link protocols for video communication
ISO 21384­4, Unmanned aircraft systems — Part 4: Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions defined in ISO/IEC 4005-1, ISO/IEC 4005-2,
ISO 21384-4 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
subchannel map
2­bit string indicating whether subchannels are available
Note 1 to entry: In wireless distributed communication, the subchannel map of each unit is generally different.
4 Abbreviated terms
CC Control Communication
1
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ISO/IEC FDIS 4005-3:2022(E)
CRC Cyclic Redundancy Check
CSCH Control Subchannel
DLL Data Link Layer
DS Dedicated Slot
FN Frame Number
IWR Initial Work Resource
LFSR Linear Feedback Shift Register
PB Parsing Block
PKH Packet Header
PN Pseudo Noise
SA Source Address
SC Shared Communication
TSB Tone Slot Block
TX Transmission
UTC Coordinated Universal Time
VC Video Communication
VSCH Video Subchannel
5 Physical layer
5.1 Channel and frame structure for data channel
5.1.1 Number of data channels and bandwidth
The number of data channels is N as shown in Figure 1. N is greater than or equal to one. The bandwidth
of one data channel is 1,25 MHz. The N is determined in the upper layer.
Figure 1 — Data channels in frequency region
5.1.2 Frame structure
The frame length of the data channel is 1 sec and consists of 500 slots and one slot time T is 2 ms as
s
shown in Figure 2. FN is a frame number that varies from 0 to 59 and has the same value as the second
of the current time.
2
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ISO/IEC FDIS 4005-3:2022(E)

a
1 frame, T = 1 sec = 500 T
f s.
b
1 slot, T = 2 ms.
s
Figure 2 — Frame structure of the control channel
5.1.3 Slot transmit time mask
The transmission time mask of a slot is shown in Figure 3.

a
2 ms.
b
Modulated signal.
Figure 3 — The transmission time mask of a slot
T , T , T , T are symbol offsets from T and symbol time is 1/672000 sec. Each value is as follows: T is
1 2 3 4 0 1
2, T is 1297, T is 1299, T is 1344.
2 3 4
T is 0 μs as the start time of the slot and the power amplifier is gated on and unmodulated fine signals
0
begin to be transmitted. T is an offset at which modulation signal transmission starts. T is an offset
1 2
at which the transmission of the modulated signal ends. T is an offset at which the power amplifier is
3
gated off, and transmission of unmodulated fine signals is stopped. The transmit power of T to T , T to
0 1 2
T shall be at least 50 dB less than the modulation signal transmit power.
3
5.1.4 Subchannels
5.1.4.1 General
One data channel consists of 20 subchannels as shown in Figure 4. Subchannel y of control channel x is
composed of the following slot set.
CCH = S , S , S , …, S
x,y x,z x,z+20 x,z+40 x,z+480
ye, venframe
z = (1)
yy+(2m− od 4)/2 ×4,  oddframe
 
where
y is subchannel number, y=0, 1, …, 19;
3
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ISO/IEC FDIS 4005-3:2022(E)
S is slot z of control channel x.
x,z


a
CCH
x
b
CCH
x,0
c
CCH
x,1
d
CCH
x,18
e
CCH
x,19
Figure 4 — Subchannel structure of control communication in even frame
A subchannel consists of 25 slots, the i­th slot resource of the subchannel y of the channel x is indicated
by SR and the subchannel y of frequency channel x is indicated by CCH . Therefore, CCH is as
x,y,i x,y x,y
follows.
CCH =…SR ,,SR ,SR (2)
xy,,xy ,,01xy ,,xy ,24
where SR is i­th slot resource of subchannel y of channel x, i=0, …, 24.
x,y,i
5.1.4.2 Up and down link decision of slot resources
For SR , 5 slots satisfying (i mod 5) =(FN mod 5) are downlink and remain 20 slots are uplink, where
x,y,i
mod means modulo operation.
5.1.5 Initial work resources (IWR) and channel
The upper layer can set the initial work resource (IWR) as follows, and the use of the IWR is determined
by the upper layer.
4
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ISO/IEC FDIS 4005-3:2022(E)
Four subchannels of frequency channel N_IWR, CCH , CCH , CCH , CCH
N_IWR,16 N_IWR,17 N_IWR,18 N_IWR,19
are designated as initial work channels. They are newly named IWRCH , IWRCH , IWRCH , IWRCH
0 1 2 3
respectively. These four initial work channels are not used for control, but are initially used to allocate
control subchannels (CSCHs) between the UA and the controller, where N_IWR is received from the
upper layer with UPtoDL.InfoIWRSlot.
The 25 slots of IWRCH are divided into five IWRs in order.
y
IR =ISRI, SR ,,,ISRISR ISR (3)
yi,,xi55xi, +15xi,,,+++25xi 35xi 4
where
y is an IWRCH number and has the value from 0 to 3;
ISR is i­th slot resource of IWRCH .
x,y,i y
5.1.6 Dedicated slots and dedicated subchannels
The upper layer can pre-determine one or more subchannels as dedicated subchannels. In this case,
the tone subslot sets mapped with the dedicated subchannel is not used as a competition tone and can
be used for other purposes. Slots in the dedicated subchannel are used as dedicated slots (DSs). One or
several dedicated slots can be assigned to UAs and controllers in advance. UAs and controllers use the
dedicated slots without competition.
It is recommended to set the dedicated subchannel in frequency channel N_IWR.
Dedicated subchannel information and dedicated slot information are received from an upper layer
through UPtoDL.InfoDedicatedChannel and UPtoDL.InfoDedicatedSlot.
5.2 Channel and frame structure for tone channel
5.2.1 Frame structure and bandwidth
The tone channel of the control communication indicates a competitive tone channel. The frame length
of tone channel is 1 sec and the number of slots per frame is 500. Four tone slots constitute one tone
slock block (TSB). Thus, there are 125 TSBs in one second frame as shown in Figure 5.

a
1 frame, T = 1 second = 500 T
f s.
b
1 slot, T = 2 ms.
s
c
1 slot block, T = 8 ms.
sb
Figure 5 — Frame structure of tone channel in control communication
The bandwidth of the tone channel is 250 kHz. FN is a frame number that varies from 0 to 59 and has
the same value as the second of the current time.
5
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ISO/IEC FDIS 4005-3:2022(E)
5.2.2 Slot transmit power
The maximum slot transmission power of the tone channel, PmaxTCH, is received as UPtoDL.
InfoPowerParamCCH from the upper layer. The transmission power of the tone subslot signal is
determined by adding the PTX_CCHTCH_differ value to the transmission power of the mapped CSCH.
5.2.3 Slot block structure
There are three types of slot blots. TSBtype0, TSBtype1, TSBtype2 are these. The type of each slot blot
of the TCH is received from the upper layer as UPtoDL.InfoTSBTypeMap.
There are 132 subslots in one slot block of TSBtype0. The length T of the subslot is 60 μs. The 132
ss
subslots are divided into four parts, as shown in Figure 6, according to each slot numbers.

a
Type 0.
b
1 slot block, T = 8 ms.
sb
c
T = 60 μs.
ss
d
40 μs.
Figure 6 — Type 0 TSB structure
In case of TSBtype0, n­th slot block is composed as follows.
— (0, 4n), (0, (4n + 1)), (0, (4n + 2)), (0, (4n + 3)), (1, 4n), (1, (4n + 1) ), (1, (4n + 2)), (1, (4n + 3)),. , (32,
4n), (32, (4n + 1)), (32, (4n + 2)), (32, (4n + 3))
where (x, y) is the x­th subslot of the y­th subslot set. The 132 subslots are divided into four subslot sets.
— {S } = {(0, 4n), (1, 4n), ., (32, 4n)}
4n
— {S } = {(0, (4n + 1)), (1, (4n + 1)), ., (32, (4n + 1))}
4n+1
— {S } = {(0, (4n + 2)), (1, (4n + 2)), ., (32, (4n + 2))}
4n+2
— {S } = {(0, (4n + 3)), (1, (4n + 3)), ., (32, (4n + 3))}
4n+3
where {S } is the x­th subslot set.
x
There are a total of 80 subslots in TSBtype1. The length T of the subslot is 100 μs. The 80 subslots are
ss
divided into four parts, as shown in Figure 7, according to each slot number.
6
  © ISO/IEC 2022 –
...