ISO/IEC 17982:2012

Information technology — Telecommunications and information exchange between systems — Close Capacitive Coupling Communication Physical Layer (CCCC PHY)

ISO 17982:2012 specifies the CCCC PHY for Full duplex and Broadcast communication in time slots on frequency division multiplex channels.

Technologies de l'information — Téléinformatique — Couche physique pour communication par couplage capacitif fermé

General Information

• Status: Withdrawn
• Publication Date: 30-Jul-2012
• Withdrawal Date: 30-Jul-2012
• ICS: 35.100.10 - Physical layer
• Technical Committee: ISO/IEC JTC 1/SC 6 - Telecommunications and information exchange between systems
• Drafting Committee: ISO/IEC JTC 1/SC 6 - Telecommunications and information exchange between systems
• Current Stage: 9599 - Withdrawal of International Standard
• Completion Date: 03-May-2021

Relations

• Revised: ISO/IEC 17982:2021 - Information technology — Telecommunications and information exchange between systems — Close capacitive coupling communication physical layer (CCCC PHY)
• Effective Date: 23-Apr-2020

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 17982
First edition
2012-08-01


Information technology —
Telecommunications and information
exchange between systems — Close
Capacitive Coupling Communication
Physical Layer (CCCC PHY)
Technologies de l'information — Téléinformatique — Couche physique
pour communication par couplage capacitif fermé




Reference number
ISO/IEC 17982:2012(E)
©
ISO/IEC 2012

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ISO/IEC 17982:2012(E)

COPYRIGHT PROTECTED DOCUMENT


©  ISO/IEC 2012
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56  CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail [e-mail]
Web www.iso.org
Published in Switzerland

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ISO/IEC 17982:2012(E)
Contents Page
Foreword . v
Introduction . vi
1  Scope . 1
2  Conformance . 1
3  Normative references . 1
4  Terms, definitions and acronyms . 1
5  Conventions and notations . 2
5.1  Representation of numbers . 2
5.2  Names . 2
6  General . 2
7  Reference plate-electrode assembly . 4
8  PHY parameters . 5
8.1  Voltage conditions . 5
8.2  Bit representation . 6
8.2.1  Bit duration . 6
8.2.2  Bit encoding . 6
8.3  Transmission . 6
8.4  DC balance of a P-PDU . 6
8.5  Reception of a P-PDU . 7
9  P-PDU . 7
9.1  Structure . 7
9.2  Space . 7
9.3  Level adjust . 7
9.4  Pre-amble and Sync . 7
9.5  Attribute . 8
9.6  TDS number . 8
9.7  Sequence number . 9
9.7.1  Initial and range . 9
9.7.2  Acknowledgement . 9
9.8  Payload . 9
9.9  CRC . 9
9.10  Post-amble . 9
9.11  Null P-PDU . 9
9.12  Data P-PDU . 9
10  PHY Data Unit (P-DU) . 9
11  Segmentation and Reassembly . 10
12  TDS . 10
13  LBT and synchronisation . 11
13.1  LBT . 11
13.2  Synchronisation . 11
14  Association procedure. 11
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ISO/IEC 17982:2012(E)
15  Communication .13
15.1  Full duplex communication .13
15.2  Broadcast communication .15
Annex A (normative) Tests .17

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ISO/IEC 17982:2012(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. In the field of information
technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. Draft International
Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75 % of the national bodies casting a vote.
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.
ISO/IEC 17982 was prepared by Ecma International (as ECMA-401) and was adopted, under a special “fast-
track procedure”, by Joint Technical Committee ISO/IEC JTC 1, Information technology, in parallel with its
approval by national bodies of ISO and IEC.
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ISO/IEC 17982:2012(E)
Introduction
This International Standard specifies the PHY protocol and for wireless communication between the Close
Capacitive Coupling Communication (CCCC) devices.

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INTERNATIONAL STANDARD ISO/IEC 17982:2012(E)

Information technology — Telecommunications and information
exchange between systems — Close Capacitive Coupling
Communication Physical Layer (CCCC PHY)
1 Scope
This International Standard specifies the CCCC PHY for Full duplex and Broadcast communication in time
slots on frequency division multiplex channels.
2 Conformance
Conforming entities implement:
 both Talker and Listener,
 listen before talk (LBT) for both Talker and Listener,
 the capability to execute association on FDC2 and to communicate on (FDC0 and FDC1), (FDC3 and
FDC4), or (FDC0, FDC1, FDC3 and FDC4),
 the capability for Talkers and Listeners to use any of the 8 TDS on a FDC,
 both Full duplex and Broadcast communication, and pass the tests in Annex A as specified herein.
3 Normative references
The following referenced documents are indispensable for the application 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 7498-1:1994, Information technology — Open Systems Interconnection — Basic Reference Model:
The Basic Model
ITU-T V.41, Data communication over the telephone network — Code-independent error-control system
4 Terms, definitions and acronyms
For the purposes of this document, the following terms and definitions apply, in addition to those defined in
ISO/IEC 7498-1:1994.
CRC Cyclic Redundancy Check
D Divisor
DUT Device Under Test
FDC Frequency Division Channel
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ISO/IEC 17982:2012(E)
LBT Listen Before Talk
LEN Length
Listener entity that does not initiate communication
P-DU PHY Data Unit
P-PDU PHY PDU
PHY Physical layer
RFU Reserved for Future Use
TDS Time Division Slot
Talker entity that initiates communication
5 Conventions and notations
5.1 Representation of numbers
The following conventions and notations apply in this document.
- A sequence of characters of ‘A’, ‘B’, ‘C”, ‘D, ‘E’ or ‘F’ and decimal digits in parentheses represent numbers
in hexadecimal notation unless followed by a ‘b’ character see next.
- Numbers in binary notation and bit patterns are represented by a sequence of 0 and 1 digits or ‘X’
characters in parentheses followed by a ‘b’ character, e.g. (0X11X010)b. Where X indicates that the
setting of a bit is not specified, and the leftmost bit is the most significant bit unless the sequence is a bit
pattern.
5.2 Names
The names of basic elements, e.g. specific fields, are written with a capital initial letter.
6 General
The protocol architecture of CCCC follows ISO/IEC 7498-1 as the basic model. CCCC devices communicate
through mediators, such as conductive and dielectric materials.
Plate-electrodes for CCCC device E and F are equivalent to the reference plate-electrode assembly.
The plate-electrode A faces to the imaginary point at infinity and the plate-electrode B faces to the mediator.
The plate-electrode C faces to the mediator and the plate-electrode D faces to the imaginary point at infinity.
See Figure 1.
Figure 2 is the equivalent circuit of Figure 1. The voltage of X is the potential of the point at infinity. The
voltage of Y is the potential of the point at infinity. It is deemed that the potential of X and Y is identical.
Therefore, X and Y is imaginary short. Consequently, device E and F is able to send and receive signal.
Regarding the information transfers from CCCC device E to F, the device E changes the voltage between
plate-electrode A and B. It changes the electric charge between plate-electrode B and the mediator. The
change in electric charge affects the device F by the capacitive coupling between plate-electrode C and
mediator. Plate-electrodes A and B and plate-electrodes C and D have potential differences of reverse
polarity; therefore device F senses the information as changes in voltage between plate-electrode C and D.
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ISO/IEC 17982:2012(E)
Plate-Electrode B
Plate-Electrode C
point at infinity
Electrostatic Electrostatic
Capacity Capacity
Mediator
Conductive
materials
point at infinity
or
point at infinity
Dielectric
materials
Plate-Electrode D
Closed Capacitive Closed Capacitive
Plate-Electrode A Coupling Com munication Coupling Com munication
Device E Device F
point at infinity

Figure 1 — Electrical model

Figure 2 — Equivalent circuit
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ISO/IEC 17982:2012(E)
Information transfer between CCCC device E and F takes place by the synchronous communication, see
13.1. 8.2.1 specifies 5 frequency division channels (FDC) by division of the centre frequency. Each FDC
consists of a sequence of time-segments. Each time-segment consists of 8 time division slots (TDS) for time
division multiple-access, see Clause 12. Peers use the Listen Before Talk (LBT) procedure in 13.1 to
ascertain that a TDS is not occupied. The TDSs are negotiated using the association procedure specified in
Clause 14.
15.1 and 15.2 specify Full duplex and Broadcast communication respectively. In Full duplex communication,
Talkers and Listeners exchange P-PDUs (see Clause 9) by synchronous communication. In Broadcast
communication Talkers broadcast P-PDUs and Listeners receive P-PDUs without acknowledging.
Length information and CRC is added to the SDU to construct a PHY Data Unit (P-DU), see Clause 10. The
sender segments the P-DU into P-PDUs. The receiving entity reassembles the P-PDUs into the P-DU, see
Clause 11, and forwards the SDU to its PHY User as illustrated in Figure 3.

Figure 3 — PHY model
7 Reference plate-electrode assembly
The reference plate-electrode assembly for the CCCC devices shall consist of plate-electrode A and plate-
electrode B specified in Figure 4. Dimensional characteristics are specified for those parameters deemed to
be mandatory.
a = 20,0 ± 0,1 mm
b = 20,0 ± 0,1 mm
The distance c between plate-electrode A and B shall be 5,0 ± 0,1 mm by horizontal flat surface.
d = 0,30 ± 0,03 mm
The displacement of centre of area e between plate-electrode A and B shall be at most 0,1 mm.
The material of the plate-electrodes shall be 99% to 100% copper or equivalent.
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ISO/IEC 17982:2012(E)
The twisted-pair wire shall be connected inside the circle area f specified in Figure 4. The f has a diameter of
2,0 ± 0,5 mm. The twisted-pair wire shall be stranded wire and 26, 27, or 28 specified American Wire Gauge
(AWG). The length of the twisted-pair wire for the reference plate-electrode assembly shall be less than 1,0 m.
a c
e
 b
f
Plate-Electrode A
d
d Twist-pair wire
Plate-Electrode B

Figure 4 — CCCC reference plate-electrode assembly
8 PHY parameters
8.1 Voltage conditions
The following conditions of the voltage between the outer and the inner plate-electrode shall be used for
communication.
 +m volts
 –m volts
 0 volt
 OPEN
The value m depends on implementations. 0 volt is achieved by shorting the two plate-electrodes in a plate-
electrode assembly. OPEN is achieved by disconnection of the plate-electrode assembly from the driver
circuits.
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ISO/IEC 17982:2012(E)
8.2 Bit representation
8.2.1 Bit duration
The centre frequency f is 40,68 MHz  50 ppm.
c
The bit duration T equals D/f seconds.
c
Table 1 specifies the relation between FDC and D.
Table 1 — FDC and D
FDC D
0 11
1 7
2 5
3 3
4 1

8.2.2 Bit encoding
Manchester bit encoding is specified in Figure 5. Depending on the relative orientation, bits are received with
either positive or negative polarity. The half bit time transition shall be between 0,4 T and 0,6 T.
Bit (1)b encoding

Bit (0)b encoding

Figure 5 — Bit encoding
8.3 Transmission
P-PDUs shall be transmitted byte-wise in the sequence specified in 9.1. Bytes shall be transmitted with least
significant bit first.
8.4 DC balance of a P-PDU
The DC balance of a P-PDU is (Sp - Sn) / (Sp + Sn) x 100 [%] where Sp is the integral of the positive voltage
parts of one P-PDU and where Sn is the integral of the negative voltage parts of one P-PDU. The DC balance
shall be less than  10 % per P-PDU.
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ISO/IEC 17982:2012(E)
8.5 Reception of a P-PDU
While receiving a P-PDU, receivers shall put the voltage condition to OPEN.
9 P-PDU
9.1 Structure
Figure 6 specifies the P-PDU as a sequence of 0,5 T of Space, 1,5 T of Level adjust, 2 T of Pre-amble, 5 T of
Sync, 2 T of Attribute, 3 T of TDS number, 2 T of Sequence number, 32 T of Payload, 16 T of CRC, and 2 T of
Post-amble. The P-PDU continues/ends with 1,5T of Level adjust and another 0,5T Space. The bit encoding
specified in 8.2.2 shall be applied to Attribute, TDS number, Sequence number, Payload, and CRC.
66 T is represented by t , t , t , … t .
1 2 3 66

Figure 6 — P-PDU structure
9.2 Space
The Space duration shall be 0,5 T with voltage condition OPEN.
9.3 Level adjust
Level adjust shall be 1,5 T of 0 volt.
9.4 Pre-amble and Sync
Figure 7 specifies Pre-amble and Sync patterns. The transmitter shall apply pattern P. If the receiver detects
Sync pattern P then it shall decode the bits in a P-PDU as positive polarity. If the receiver detects Sync pattern
Q then it shall decode the bits in a P-PDU as negative polarity. The divisor value shall be detected from Pre-
amble and Sync. Other patterns shall not be handled as Pre-amble and Sync.
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ISO/IEC 17982:2012(E)

Figure 7 — Pre-amble and Sync patterns
9.5 Attribute
Table 2 specifies the bit encodings of the attribute settings in a P-PDU.
Table 2 — Attribute settings
 Definition
FDC2 FDC0, FDC1, FDC3, and FDC4
t t
10 11
0 0 Association Request 1 or Null P-PDU
Association Response 2
0 1 Association Response 2 or The last Data P-PDU
Association Request 2
1 0 RFU The first Data P-PDU
1 1 RFU Data P-PDU between the first and the last Data P-PDU
If a receiver gets RFU attribute settings it shall ignore the P-PDU and stay mute.
9.6 TDS number
The TDS number field shall indicate the slot number in which the P-PDU is send; numbers 1 to 8 are identified
by (000)b to (111)b.
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ISO/IEC 17982:2012(E)
9.7 Sequence number
9.7.1 Initial and range
P-PDUs shall be identified by the sequence numbers in the range of (00)b to (11)b. The first P-PDU shall have
(00)b in the sequence number field.
9.7.2 Acknowledgement
To acknowledge correct reception, receivers shall increment the sequence number by 1 (modulo 4) from the
correctly received P-PDU as the sequence number in the next P-PDU.
9.8 Payload
The payload field of a P-PDU contains 4 bytes.
9.9 CRC
The scope of CRC shall be the last 1 T of Sync as a bit, Attribute, TDS number, Sequence number, and
Payload. The CRC shall be calculated according to ITU-T V.41 with pre-set value (FF FF). If the CRC of the
received P-PDU and the calculated CRC upon reception differ, the P-DU shall be ignored.
Example: with Attribute (11)b, TDS number (010)b, Sequence number (10)b, Payload (55 AA 00 FF) the CRC is (6F AB).
9.10 Post-amble
Post-ambles consist of 1,5 T of Level adjust and 0,5 T of Space.
9.11 Null P-PDU
Null P-PDUs have Attribute of (00)b and a payload (00 00 00 00).
9.12 Data P-PDU
Data P-PDUs have a payload with a (possibly segmented) P-DU.
10 PHY Data Unit (P-DU)
Figure 8 specifies the P-DU. It shall consist of LEN, SDU, and CRC.

Figure 8 — PHY Data Unit (P-DU)
LEN contains the length of SDU in bytes + 2. The CRC shall be calculated over the LEN value and the SDU
according to ITU-T V.41. The pre-set value shall be (FFFF).
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ISO/IEC 17982:2012(E)
11 Segmentation and Reassembly
P-DU shall be segmented and reassembled into 4 byte payloads of P-PDU as illustrated in Figure 9, by using
the Attribute settings in Table 2.

Figure 9 — Segmentation and Reassembly
12 TDS
A TDS is 64 T wide. A P-PDU which is 66 T wide (see Figure 6), shall be transmitted in one TDS. See
Figure 11.
TDSs shall be numbered from 1 to 8 in each time segment as illustrated in Figure 10.

Figure 10 — Time-segment and TDS

Figure 11 — Mapping of a P-PDU and a TDS
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Pre-amble
Sync
Attribute
TDS n
Sequence
Payload
CRC

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ISO/IEC 17982:2012(E)
This International Standard specifies Full duplex and Broadcast communication. A TDS is used for
unidirectional communication. A Full duplex channel consists of two TDSs and one TDS is used for Broadcast
communication.
The TDS may be either fixed by configuration or be negotiated.
Talkers may either use fixed configured TDS(s) on FDC1 or FDC3 or alternatively negotiate using TDS(s) on
FDC1 or FDC3 using the association procedure. Talkers that select FDC0 or FDC4 shall negotiate TDS using
the association procedure in Clause 14.
Before using a TDS, entities shall use LBT and synchronisation.
13 LBT and synchronisation
13.1 LBT
During LBT, entities shall listen for 576 T on the selected FDC to seek a free TDS. A TDS is occupied when
the entities receive a correct P-PDU.
13.2 Synchronisation
If all TDSs on the FDC that the Talker selects are found to be free using LBT, then that Talker shall generate
the TDS timing on its selected FDC. Otherwise the Talkers shall synchronise to the TDS timing on the FDC
using LBT. Listeners shall always synchronise to the TDS timing on the FDC using LBT.
14 Association procedure
Talkers use the association procedure to negotiate the communication TDS(s). During this procedure, Talkers
and Listeners exchange the P-PDUs on 2 Full duplex TDS in FDC2, in the following steps:
1. Talker selects a free association TDS in the range from 0 to 3 in FDC2, using LBT.
2. Talker selects (1 for Broadcast and 2 for Full duplex) free slot(s) in an FDC other than FDC2, using LBT.
3. Talker sends Association Request 1 P-PDU specified in Table 3 on the association TDS from step 1 with
Attribute (00)b, Sequence number (00)b and FDC/TDS(s) from step 2 and the selected communication
mode.
4. Listener sends Association Response 1 P-PDU specified in Table 4 on the association TDS number + 4
with Attribute (01)b, Sequence number (01)b and random number.
5. Talker sends Association Request 2 P-PDU specified in Table 4 on the association TDS from step 1 with
Attribute (01)b, Sequence number (10)b and the random number from Association Response 1.
6. Listener sends Association Response 2 P-PDU specified in Table 3 on the association TDS number + 4
with Attribute (00)b, Sequence number (11)b and FDC/TDS(s) from Association Request 1.
7. Peers attempt communication as specified in Clause 15 on the FDC/TDS(s) from Association Request 1.
8. If the FDC/TDS(s) from Association Request 1 are occupied peers may repeat this association procedure.
Figure 12 illustrates steps 3 to 6.
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ISO/IEC 17982:2012(E)

Figure 12 — Association
Table 3 — Payload with parameters of Association Request 1 and Association Response 2 P-PDU
Payload
Settings
t
48

t
47

.

.
Shall be one’s complement of t , t , t , t , t , t , t , t , t , t , t , t , t , t , t , t
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
.



t
34

t
33
t RFU
32
t RFU
31
t RFU
30
t RFU
29
t RFU
28
t
0 Full duplex 0 Broadcast
27
t 0 communication 1 communication Other settings are RFU
26
t 0 0
25
t 0 Listener 1 Listener 0 Listener 1 Listener 0 Listener 1 Listener 0 Listener 1 Listener
24
t 0 uses 0 uses 1 uses 1 uses 0 Uses 0 uses 1 uses 1 uses
23
t 0 TDS 1 0 TDS 2 0 TDS 3 0 TDS 4 1 TDS 5 1 TDS 6 1 TDS 7 1 TDS 8
22
t 0 Talker 1 Talker 0 Talker 1 Talker 0 Talker 1 Talker 0 Talker 1 Talker
21
t
20 0 uses 0 uses 1 uses 1 uses 0 Uses 0 uses 1 uses 1 uses
t 0 TDS 1 0 TDS 2 0 TDS 3 0 TDS 4 1 TDS 5 1 TDS 6 1 TDS 7 1 TDS 8
19
t 0 Use FDC 0 1 Use FDC 4 Other settings are RFU
18
t 0 1
17

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ISO/IEC 17982:2012(E)
Table 4 — Payload with parameters of Association Response 1 and Association Request 2 P-PDU
Payload Settings
t
48
t
47

.

.
. Shall be one’s complement of t , t , t , t , t , t , t , t , t , t , t , t , t , t , t , t
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32


t
34

t
33
t
32

t
31

.

.
Random number
.



t
18

t
17

15 Communication
Entities exchange P-PDUs (see Clause 11) using either Full duplex or Broadcast communication.
Entities shall send Null P-PDUs when there is no P-DU (see Clause 10) pending until the PHY User stops
communication.
15.1 Full duplex communication
See 9.7.1 for the rules on the sequence numbering.
The sender shall resend the current P-PDU until it is acknowledged. See 9.7.2.
The next P-PDU shall have a sequence number of the (last received sequence number + 1) modulo 4.
Figure 13 illustrates Full duplex communication without any errors.
Figure 14 illustrates a Full duplex communication flow with receive errors.
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ISO/IEC 17982:2012(E)

Figure 13 — Example flow of Full duplex communication

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ISO/IEC 17982:2012(E)
Talker Listener
Sequence number (00)b
reset the sequence number Send
Receive
Sequence number (00)b
Resend same P-PDU
Receive
Sequence number (00)b
Resend same P-PDU
Receive
increment the sequence number
Sequence number (01)b
Send
Receive (fail)
Sequence number (00)b
Resend same P-PDU
Receive
Sequence number (01)b
Resend same P-PDU
Receive
Sequence number (10)b
Send
Receive (fail)
Sequence number (01)b
Resend same P-PDU
Receive

Figure 14 — Example flow of Full duplex communication with some resending
15.2 Broadcast communication
Broadcast communication is unidirectional and unacknowledged.
For broadcast communication, the Talker (hereafter referred to as Broadcaster) shall use the LBT procedure
in 13.1 to find a free TDS on FDC0 or FDC4.
Any numbers of receivers may receive broadcasted P-PDUs.
See 9.7.1 for the rules on the sequence numbering.
The Broadcaster may repeatedly send identical P-PDUs. The next P-PDU shall have a sequence number of
the (last sent sequence number + 1) modulo 4.
Note: Repeating identical P-PDUs may increase communication robustness.
Figure 15 illustrates broadcast communication flow. In this example, the Broadcaster sends identical P-PDUs
in 2 time-segments.
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ISO/IEC 17982:2012(E
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