FprEN IEC 62980:2022

Parasitic communication protocol for radio-frequency wireless power transmission

This standard defines procedures for transferring power to non-powered IoT devices using the existing ISM band communication infrastructure and RF WPT and a protocol for a two-way, long-distance wireless network in which IoT devices and APs communicate using backscatter modulation of ISM-band signals. Three components are required for two-way, long-distance wireless communication using backscatter modulation of ISM-band signals: an STA that transmits wireless power and data packets to SSNs by forming ISM-band signal channels between HIE-APs, a batteryless SSN that changes the sensitivity of the channel signals received from the STA using backscatter modulation, and an HIE-AP that practically decodes the channel signals whose sensitivity was changed by the SSN. In this standard, the procedures for CW-type RF WPT using communication among these three components are specified based on application of the CSI or RSSI detection method of ISM-band communication. This standard proposes a convergence communication protocol than can deploy sensors, which can operate at low power (dozens of microwatts or less) without batteries, collect energy, and perform communication, to transmit power to SSNs using RF WPT based on parasitic communication. This method can be applied to application service areas such as domestic IoT, the micro-sensor industry, and industries related to environmental monitoring in the future

Parasitäres Kommunikationsprotokoll für drahtlose Hochfrequenz-Leistungsübertragung

Protocole de communication parasite pour le transfert d'énergie sans fil par rayonnement radiofréquence

L'IEC 62980:2022 définit les procédures de transfert d'énergie vers des dispositifs d'IoT au moyen de l'infrastructure de communication existante sur les bandes ISM et du WPT RF, ainsi qu'un protocole de réseau sans fil longue distance bidirectionnel qui permet aux dispositifs d'IoT et aux points d'accès de communiquer par modulation de rétrodiffusion des signaux sur les bandes ISM. La communication sans fil longue distance bidirectionnelle fondée sur la modulation de rétrodiffusion des signaux sur les bandes ISM exige trois éléments: • une STA qui assure le transfert sans fil de l'énergie et des paquets de données vers les SSN en créant des canaux de signaux dans les bandes ISM entre HIE-AP ; • un SSN sans batterie qui modifie, par modulation de rétrodiffusion, la sensibilité des signaux de canal reçus depuis la STA ; et • un HIE-AP qui décode de manière pratique les signaux du canal dont la sensibilité a été modifiée par le SSN. Dans le présent document, les procédures de WPT RF de type CW qui utilisent la communication entre ces trois éléments sont spécifiées à partir de l'application d'une méthode de détection des CSI ou du RSSI de la communication sur les bandes ISM. Le présent document propose un protocole de communication convergent qui peut déployer des capteurs, lesquels peuvent fonctionner à faible puissance (quelques dizaines de microwatts ou moins) sans batteries, collecter de l'énergie et assurer une communication, afin d'alimenter des SSN au moyen d'un WPT RF fondé sur une communication parasite. Cette méthode pourra être appliquée ultérieurement à des services d'application tels que l'IoT domestique, l'industrie des microcapteurs et les industries impliquées dans la surveillance de l'environnement.

Lažni komunikacijski protokol za brezžični radiofrekvenčni prenos električne energije (TA 15)

General Information

• Status: Not Published
• ICS: 29.240.99 - Other equipment related to power transmission and distribution networks
• Technical Committee: CLC/TC 100X - Audio, video and multimedia systems and equipment and related sub-systems
• Drafting Committee: IEC/TC 100 - IEC_TC_100
• Current Stage: 5020 - Vote circulated
• Due Date: 25-Oct-2021
• Ref Project: kSIST FprEN IEC 62980:2022 - Parasitic communication protocol for radio-frequency wireless power transmission (TA 15)

Standards Content (sample)

SLOVENSKI STANDARD
oSIST prEN IEC 62980:2021
01-marec-2021
Lažni komunikacijski protokol za brezžični radiofrekvenčni prenos električne
energije (TA 15)

Parasitic communication protocol for radio-frequency wireless power transmission (TA

15)

Protocole de communication parasite pour le transfert d'énergie sans fil par rayonnement

radiofréquence (TA 15)
Ta slovenski standard je istoveten z: prEN IEC 62980:2021
ICS:
33.160.01 Avdio, video in avdiovizualni Audio, video and audiovisual
sistemi na splošno systems in general
oSIST prEN IEC 62980:2021 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN IEC 62980:2021
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oSIST prEN IEC 62980:2021
100/3533/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 62980 ED1
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2021-01-08 2021-04-02
SUPERSEDES DOCUMENTS:
100/3379/CD, 100/3458A/CC
IEC TA 15 : WIRELESS POWER TRANSFER
SECRETARIAT: SECRETARY:
Korea, Republic of Mr Ock-Woo Nam
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:
Other TC/SCs are requested to indicate their interest, if
any, in this CDV to the secretary.
FUNCTIONS CONCERNED:
EMC ENVIRONMENT QUALITY ASSURANCE SAFETY

SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING

Attention IEC-CENELEC parallel voting
The attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft
for Vote (CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
CENELEC online voting system.

This document is still under study and subject to change. It should not be used for reference purposes.

Recipients of this document are invited to submit, with their comments, notification of any relevant patent rights of

which they are aware and to provide supporting documentation.
TITLE:

Parasitic communication protocol for radio-frequency wireless power transmission (TA 15)

PROPOSED STABILITY DATE: 2025
NOTE FROM TC/SC OFFICERS:

Copyright © 2020 International Electrotechnical Commission, IEC. All rights reserved. It is permitted to download this

electronic file, to make a copy and to print out the content for the sole purpose of preparing National Committee positions.

You may not copy or "mirror" the file or printed version of the document, or any part of it, for any other purpose without

permission in writing from IEC.
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oSIST prEN IEC 62980:2021
IECCDV 62980 ED1© IEC 2020 2 100/3533/CDV
Rev Date Description
01 2017.10.11 Circulation to experts for review
02 2018.01.18 Modified draft version of working document after getting
comments or proposed change of NP voting
03 2018.09.04 Modified draft version of working document after getting
editorial comments or proposed change from experts
04 2019.04.05 1 CD circulation document
05 2020.01.02 modified after 1 CD circulation document
06 2020.05.21 2 CD circulation document
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23 CONTENTS

25 1. Scope ............................................................................................................................... 8

26 2. Normative references ....................................................................................................... 8

27 3. Definitions and terminology .............................................................................................. 8

28 4. Overview ........................................................................................................................ 11

29 5. Communication procedures for RF WPT ......................................................................... 13

30 5.1. General ................................................................................................................. 13

31 5.2. Communication procedures for parasitic downlink communication ......................... 13

32 5.3. Communication procedures for parasitic uplink communication ............................. 14

33 5.4. Backscatter downlink/uplink data flow ................................................................... 15

34 5.5. WPT process ......................................................................................................... 16

35 Physical Layer ................................................................................................................ 18

36 6.1. Modulation/coding method ..................................................................................... 18

37 6.1.1. Downlink modulation method ..................................................................... 18

38 6.1.2. Uplink modulation method ......................................................................... 18

39 Downlink coding method ............................................................................ 18

6.1.3.

40 6.1.4. Uplink coding method ................................................................................ 19

41 6.2. Frame structure ..................................................................................................... 20

42 6.2.1. Downlink frame structure ........................................................................... 20

43 6.2.2. Uplink frame structure ............................................................................... 21

44 7. Datalink Layer ................................................................................................................ 24

45 7.1. Message definition ................................................................................................ 24

46 7.1.1. Select step ................................................................................................ 27

47 7.1.2. Inventory step ............................................................................................ 28

48 7.1.3. Access step ............................................................................................... 31

49 Data encoding ....................................................................................................... 32

7.2.

50 7.2.1. FM0 encoding ............................................................................................ 33

51 7.2.2. Miller encoding .......................................................................................... 34

52 8. RF WPT control protocol ................................................................................................ 36

53 Wireless charging architecture .............................................................................. 36

8.1.

54 8.1.1. Power control purpose of RF WPT ............................................................. 36

55 8.1.2. HIE-AP operation control ........................................................................... 37

56 8.1.3. SSN operation control ............................................................................... 37

57 8.2. RF WPT process ................................................................................................... 38

58 8.2.1. General WPT management ........................................................................ 39

59 SSN control ............................................................................................... 40

8.2.2.

60 8.2.3. SSN static parameter ................................................................................ 41

61 8.2.4. SSN dynamic parameter ............................................................................ 42

62 Figure 1 — Example/Application Usage of RF-WPT ............................................................. 11

63 Figure 2 — RF-WPT structure of using parasitic Wi-Fi communication technology ................ 12

64 Figure 3 — Parasitic downlink/uplink communication procedures .......................................... 13

65 Figure 4 — Specific parasitic downlink communication procedures ....................................... 14

66 Figure 5 — Specific parasitic uplink communication procedures ............................................ 15

67 Figure 6 — Data flow during parasitic downlink/uplink communication .................................. 16

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68 Figure 7 — RF WPT access procedures ............................................................................... 16

69 Figure 8 — RF WPT control protocol ..................................................................................... 17

70 Figure 9 — PIE method packet configuration ........................................................................ 18

71 Figure 10 — Modulation and coding of the downlink preamble .............................................. 19

72 Figure 11 — Modulation and coding of the downlink preamble .............................................. 19

73 Figure 12 — Modulation and coding of the uplink preamble .................................................. 19

74 Figure 13 — Modulation and coding of the uplink payload ..................................................... 19

75 Figure 14 — Physical layer structure of the downlink frame .................................................. 20

76 Figure 15 — Physical layer structure of the uplink frame ....................................................... 22

77 Figure 16 — Model of command transmission between the STA and SSN ............................. 24

78 Figure 17 — Diagram of sequential command transmission between the STA and SSN ........ 25

79 Figure 18 — SSN memory structure ...................................................................................... 26

80 Figure 19 — Message exchange in the select step................................................................ 27

81 Figure 20 — CRC-16 circuit example .................................................................................... 28

82 Figure 21 — Message exchange method of the inventory step .............................................. 29

83 Figure 22 — Basic functions for FM0 encoding ..................................................................... 33

84 Figure 23 — State diagram for FM0 encoding generation ...................................................... 33

85 Figure 24 — Basic functions for Miller encoding .................................................................... 34

86 Figure 25 — State diagram for FM0 encoding generation ...................................................... 34

88 Table 1 – Downlink preamble structure ................................................................................. 20

89 Table 2 – Downlink payload structure ................................................................................... 21

90 Table 3 – Downlink frame check CRC ................................................................................... 21

91 Table 4 – Uplink preamble structure ...................................................................................... 22

92 Table 5 – Uplink frame detection field structure .................................................................... 22

93 Table 6 – Downlink payload structure ................................................................................... 23

94 Table 7 – CMD list ................................................................................................................ 25

95 Table 8 – Responses for each CMD ...................................................................................... 25

96 Table 9 – Select CMD ........................................................................................................... 28

97 Table 10 – Valid response .................................................................................................... 28

98 Table 11 – Query CMD field .................................................................................................. 29

99 Table 12 – QueryRep CMD field ........................................................................................... 30

100 Table 13 – QueryAdj CMD field ............................................................................................. 30

101 Table 14 – Valid_Query response field .................................................................................. 30

102 Table 15 – Ack CMD field ..................................................................................................... 31

103 Table 16 – Valid_Ack response field list ................................................................................ 31

104 Table 17 – Read CMD field ................................................................................................... 31

105 Table 18 – Data field of the response to the read command .................................................. 32

106 Table 19 – Write CMD field ................................................................................................... 32

107 Table 20 – Data field of the response to the write command ................................................. 32

108 Table 21 – WPT CMD field .................................................................................................... 39

109 Table 22 – WPT sub-CMD list ............................................................................................... 40

110 Table 23 – SSN control field ................................................................................................. 40

111 Table 24 – Detailed WPT field description ............................................................................. 40

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112 Table 25 – Response to the SSN control CMD ...................................................................... 41

113 Table 26 – SSN static parameter field ................................................................................... 41

114 Table 27 – Rectifier maximum power field ............................................................................. 41

115 Table 28 – Rectifier minimum constant voltage ..................................................................... 41

116 Table 29 – Rectifier maximum constant voltage .................................................................... 42

117 Table 30 – Rectifier minimum constant voltage ..................................................................... 42

118 Table 31 – SSN dynamic parameter field .............................................................................. 42

119 Table 32 – Rectifier dynamic voltage field ............................................................................. 42

120 Table 33 – Rectifier dynamic current field ............................................................................. 42

121 Table 34 – Output dynamic voltage of the battery terminal .................................................... 43

122 Table 35 – Output dynamic current of the battery terminal .................................................... 43

123 Table 36 – Battery temperature of the SSN ........................................................................... 43

124 Table 37 – SSN critical state field ......................................................................................... 43

125 Table 38 – Rectifier desired minimum voltage ....................................................................... 43

126
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127 INTERNATIONAL ELECTROTECHNICAL COMMISSION
128 ____________
129
130 PARASITIC COMMUNICATION PROTOCOL
131 FOR RADIO-FREQUENCY WIRELESS POWER TRANSMISSION
132
133 FOREWORD

134 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising all national

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164 International Standard IEC XXX has been prepared by subcommittee XX: TITLE, of IEC technical

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167

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180 PUBLICATION STAGE.
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181 INTRODUCTION

182 The [IEC 62980 (Parasitic communication protocol for radio-frequency wireless power

183 transmission)] standard provides a parasitic backscatter communication protocol for battery-

184 less internet-of-things (IoT) devices and sensors for radio-frequency (RF) wireless power

185 transmission (WPT) without additional infrastructure.
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186 Parasitic communication protocol for radio-frequency wireless power
187 transmission
188
189 1. Scope

190 This standard defines procedures for transferring power to non-powered IoT devices using the

191 existing ISM band communication infrastructure and RF WPT and a protocol for a two-way,

192 long-distance wireless network in which IoT devices and APs communicate using backscatter

193 modulation of ISM-band signals. Three components are required for two-way, long-distance

194 wireless communication using backscatter modulation of ISM-band signals: an STA that

195 transmits wireless power and data packets to SSNs by forming ISM-band signal channels

196 between HIE-APs, a batteryless SSN that changes the sensitivity of the channel signals

197 received from the STA using backscatter modulation, and an HIE-AP that practically decodes

198 the channel signals whose sensitivity was changed by the SSN. In this standard, the

199 procedures for CW-type RF WPT using communication among these three components are

200 specified based on application of the CSI or RSSI detection method of ISM-band

201 communication.

202 This standard proposes a convergence communication protocol than can deploy sensors,

203 which can operate at low power (dozens of microwatts or less) without batteries, collect

204 energy, and perform communication, to transmit power to SSNs using RF WPT based on

205 parasitic communication. This method can be applied to application service areas such as

206 domestic IoT, the micro-sensor industry, and industries related to environmental monitoring in

207 the future
208
209 2. Normative references
210 Not applicable.
211
212 3. Definitions and terminology

213 For the purposes of this document, the following terms, definitions, and abbreviations apply.

214 3.1. Definitions
215 3.1.1.
216 BCU (Backscatter Communication Unit)

217 A BCU is a device that responds to a command from an STA with backscatter through load

218 modulation and enables communication without power.
219 3.1.2.
220 BU (Battery Unit)

221 BUs are batteries and circuits capable of receiving wireless power to support the operations

222 of devices and sensors.
223 3.1.3.
224 HIE-AP (Hybrid Information and Energy Access Point)

225 An HIE-AP practically decodes the channel signals whose sensitivity was changed by the SSN

226 into digital signals of 0 or 1. It forms an STA and ISM-band channels for communication,

227 detects the CSI or RSSI level of the response using backscatter from the SSN, and transmits

228 the response data from the SSN to the STA. It also transmits CW-type power to the SSN for

229 RF WPT.
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230 3.1.4.
231 Impedance modulation

232 A method of changing the sensitivity of the received signal from the channel between the STA

233 and HIE-AP using backscatter modulation in the SSN according to the data.
234 3.1.5.
235 SSN (Smart Sensor Node)

236 An SSN is a device that changes the sensitivity of the received channel signals using

237 backscatter modulation. SSNs include IoT devices, wearable devices, and micro-sensors. An

238 SSN consists of a backscatter communication unit (BCU) that supports communication without

239 power, smart sensor unit (SSU) that identifies various sensors, and battery unit (BU) that

240 receives WPT.
241 3.1.6.
242 SSU (Smart Sensor Unit)

243 SSUs are various sensors that can be attached to SSNs. Each sensor requires a different

244 amount of power.
245 3.1.7.
246 STA (Station)

247 An STA is a device that can perform communication by occupying an ISM-band channel. It

248 transmits wireless power and data packets to SSNs by forming a channel and using the pulse

249 interval encoding (PIE) method.
250
251 3.2. Abbreviations
252 For the purposes of this document, the following abbreviations apply:
253 3.2.1.
254 ASK
255 Amplitude shift keying
256 3.2.2.
257 BCU
258 Backscatter Communication Unit
259 3.2.3.
260 BU
261 Battery Unit
262 3.2.4.
263 CRC
264 Cyclic Redundancy Check
265 3.2.5.
266 CSI
267 Channel State Information
268 3.2.6.
269 CW
270 Continuous Wave
271 3.2.7.
272 FCS
273 Frame Check Sequence
274
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275 3.2.8.
276 HIE-AP
277 Hybrid Information and Energy Access Point
278 3.2.9.
279 ISM
280 Industrial scientific and medical equipment
281 3.2.10.
282 PIE
283 Pulse interval encoding
284 3.2.11.
285 RFID
286 Radio-Frequency Identification
287 3.2.12.
288 RFU
289 Reserved for Future Use
290 3.2.13.
291 RSSI
292 Received signal strength indicator
293 3.2.14.
294 RWP
295 Response Waiting Packet
296 3.2.15.
297 SSN
298 Smart Sensor Node
299 3.2.16.
300 SSU
301 Smart Sensor Unit
302 3.2.17.
303 STA
304 Station
305
306
307
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308
309 4. Overview

310 RF WPT includes WPT using energy harvesting, magnetic induction, or magnetic resonant

311 methods and involves the wireless transmission of power to sensors and facilities for practical

312 use by employing RF waves. This standard proposes a method of performing RF WPT to

313 batteryless sensors or facilities. The overall structure of parasitic communication for RF WPT

314 proposed in this standard is depicted in figure 1. Parasitic communication (or Ambient

315 backscatter) uses existing radio frequency signals, such as radio, television and mobile

316 telephony, to transmit data without a battery or power grid connection. Each such device uses

317 an antenna to pick up an existing signal and convert it into tens to hundreds of microwatts of

318 electricity. This standard defines procedures for bi-directional, long-distance wireless

319 communication protocol for communication using backscatter modulation of industrial,

320 scientific, and medical (ISM)-band frequency signals between stations (STA) and smart

321 sensor nodes (SSNs), such as IoT devices, sensors, tags, and wearable devices, and for RF

322 WPT from a hybrid information and energy access point (HIE-AP) to nearby SSNs.

323
324 Figure 1 — Example/Application Usage of RF-WPT
325

326 Three components are required for the bi-directional, long-distance wireless communication

327 protocol using backscatter modulation of ISM-band signals as shown in figure 2:

328

329  STA: performing communication by occupying a communication channel and transmits

330 wireless power and data packets for communication to the SSN in the PIE method.

331  HIE-AP: decoding the channel signals whose sensitivity was changed by the SSN into

332 digital signals of 0 or 1. It forms a channel with the STA for communication, detects

333 the CSI level of the response from the SSN that used backscatter, and transmits the

334 response data from the SSN to the STA. It also transmits CW-type power to the SSN

335 for RF WPT.

336  SSN: changing the sensitivity of the channel signals received from the STA using

337 backscatter modulation and consists of a BCU, an SSU, and a BU.
338  BCU: responding to a command from an STA with backscatter through load
339 modulation and can respond with backscatter using the wireless power
340 transmitted by the STA.

341  SSU: various sensors that can be attached to the SSN, each of which requires a

342 different amount of power.

343  BU: a battery or a circuit capable of receiving wireless power to support the

344 operation of nodes and sensors.
345
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346

347 Figure 2 — RF-WPT structure of using parasitic Wi-Fi communication technology

348 RF power is first transmitted from the STA to the SSN to drive the BCU of the SSN, to

349 summarize the operation process. Then, the SSN sends its data for the STA to the channel

350 formed between the STA and HIE-AP by changing its load, and the HIE-AP can receive data

351 from the SSN by decoding the CSI level of the information sent from the SSN. The information

352 sent from the SSN includes ID information, battery information, and sensor data. The STA

353 sends wireless power to the HIE-AP. The HIE-AP performs and controls RF WPT in real time

354 based on the information received from the SSN on battery, voltage of the SSN itself, and

355 remaining battery l
...