Current Research and Development ofWireless Power Transfer via Radio Waves

and the Application [DML]

Jan 25, 2018

@ University of Perugia

Naoki Shinohara, Professor,

Research Institute for Sustainable Humanosphere, Kyoto University

shino@rish.kyoto-u.ac.jp1

Contents1. Introduction2. Overview of Wireless Power Transfer via Radio Waves3. Wireless Power Transfer via Radio Waves in Far Field4. Toward New Radio Wave Regulation of WPT5. Introduction of Activities of WPT in IEEE and IEICE6. Conclusion

2

SHARP Airplane exp.1987@Canada

MPT to helicopterBy W. Brown 1964, 1968

MPT rocket exp.1983 by Kyoto Univ., ISAS

Island-Island MPT (150km)in Hawaii2008 by Kobe Univ., NASA

3

Introduction

Kyoto and Kyoto University

4

KyotoWinter

Autumn

Spring APMC2018 will be held at Kyoto.

- Kyoto Univ. Data (2015) -

Professors : 1,032 (5,445 Employees)

Students : 13,569 (Under Graduate)

4,773 (Master), 3,671 (Ph.D)

Novel Prizes (Prof. Yamanaka, Prof. Yukawa,

Prof. Tomonaga, Prof. Tonegawa, Prof. Fukui..)

Main Campus

Uji Campus

Kyoto Univ.

Kyoto Univ.

Tokyo

5

What is ‘Wireless Power Transfer’?

Power Transmission

・Power transfer frompower station to homevia wire

Wireless Communication

TV

Mobile

Radio

・Information transfer frombase station to uservia radio wave

+ =Wireless PowerTransfer (WPT)

・Power transfer fromtransmitter to uservia electromagnetic fieldor radio wave

Various Wireless Power Transfer

Ｉ

Ｉ

H

Supply

User

Ｉ

Ｉ

H

Supply

User

L

L

C

C

Resonance of L and C

Transmitter

Transmitted

Power

Receiver

→PowerOnly Carrier for WPT

Very Narrow

Electric Power

To User

Frequency

Time and

Space

Inductive

Coupling

(Magnetic)

Resonance

Coupling

Capacitive

Coupling

6

E

V

V

Radio Waves

(Microwaves)

RISH, Kyoto Univ.

Microwave Power Transmission Field Experiment in Kyoto Univ.

1993

Second MPT Rocket

Experiment

- ISY-METS -

1994-95

Ground-to-Ground

MPT Experiment

1996

Retrodirective

MPT System

Open Experiment

1983

First MPT Rocket Experiment

In the World - MINIX-1992

MPT Experiment to

Fuel-free Airplane

- MILAX -

2001

Solar Power

Radio Integrated

Transmitter

- SPRITZ -

2009

Airship-to-Ground

MPT Experiment

7

8

Jan., 1983, by Kyoto Univ.. and ISAS

9

Aug., 1992, by Kyoto Univ., Kobe Univ., CRL, etc

10

Power from Airship (50m above, 2.45GHz, phased array with two magnetrons)

March, 2009, at Uji, Kyoto, Japan

11

Overview of Wireless Power Transfer

via Radio Waves

Brief History of WPT• 1864 Prediction of Radio Waves by establishment of

Maxwell’s Equation based on Ampere’s law and Faraday’s law. (Radio waves was found in 1888 by Hertz’s experiment)

• Around 1900 Tesla carried out WPT experiment of both inductive WPT and WPT via radio wave (150kHz), -> faired

• 1960s W. Brown carried out beam-type WPT via microwave (2.45GHz) -> succeeded

• 1980s Commercial Products of inductive WPT (Shaver, IC card..)

• 1990s 1) RF-ID, 2) RF WPT toward Solar Power Satellite in Japan

• 2006 MIT group proposed resonance coupling WPT (revised inductive coupling)

• 2010s Various WPT – Standardization of inductive WPT, wireless charger for EV, energy harvesting from broadcasting waves, ubiquitous RF-WPT…

12

Various Wireless Charger Products

13

Inductive WPT (kHz-MHz) Radio Waves (Microwaves, GHz)

Silicon Valley’s Rumor (Nov., 2016)

• iPhone8 will install chip of Wireless Charging via Radio Wave by Energous

“With an Energous transmitter in your office, your phone will constantly be charging even while it’s in your pocket as you sit at your desk and work.”

14

https://www.bloomberg.com/news/articles/2016-01-29/apple-said-developing-wireless-charged-phone-for-as-soon-

as-2017-ijz3i4si

http://www.phonearena.com/news/Upcoming-iPhone-8-could-feature-wireless-charging-unlike-anything-weve-

seen-yet_id87639

Energous Receives Industry-First FCC Certification for Over-the-Air, Power-at-a-Distance Wireless Charging (2017/12/26)

The company's WattUp Mid Field transmitter can deliver power via radio frequency (RF) energy to WattUp-enabled electronic devices at a distance of up to three feet.

15

https://ir.energous.com/press-releases/detail/596/energous-

receives-industry-first-fcc-certification-for

t t

RF Amplifier Rectifier

(+ Antenna = Rectenna)

Transmitting

AntennaRF Choke

(DC Bias)

RF Choke

(DC Bias) DC

Block

VDD-VG

R０

Imp

ed

an

ce

Ma

tch

ing

Circ

uit (N

o

Lo

ss)

Impedance M

atc

hin

g

Circ

uit

or H

igher H

arm

onic

s

Resonato

rs

FET,

HEMT,

etc.

Imp

ed

an

ce

Ma

tch

ing

Circ

uit

an

d L

ow

Pa

ss

Filte

r

RL

DC

Block

Receiving

Antenna

Electromagnetic

ally

Uncoupled

Source

Impedance M

atc

hin

g

Circ

uit

or H

igher H

arm

onic

s

Resonato

rs

Diode

User

DC

I V I V I V I V I V I V

Wireless Power Transfer via Radio Waves

16

Field of Radio Waves

17

2

2

2

2

Dd

Dd

d

I : Reactive Near Field

II : Radiative Near Field (Fresnel Region)

III : Far Field (Fraunhofer Region)

[Antenna Element] [Aperture Antenna]

Electric Field from Aperture Antenna

in Near Field and Far Field

II : Radiative Near Field (Fresnel Region)

= Sphere Wave (Beam-type WPT)

III : Far Field (Fraunhofer Region)

= Plane Wave (approximation) (Ubiquitous WPT)

I : Reactive Near Field = Inductive WPT

Various Wireless Power Transfer via Radio Waves(a) Beam-type

(High efficiency with higher frequency)

(b)Ubiquitous-type (Low efficiency, like RF-ID)

(c) Energy Harvesting

(No power source)

Transmitter

Receiver

→Power

Time and Space

Information

Frequency

Wide

Electric Power

to User Receiver

→Power

Transmitted

Power

Transmitted

Power

Transmitted

Power

Transmitter

Transmitted

Power (Broad)

→ Electric

PowerOnly Carrier for WPT

Very Narrow

Frequency

Time and

Space

→ Electric

Power→ Electric

Power

18

(d) In Closed Area (like Waveguide)

Transmitter

Transmitted Power

Receiver→

Power

19

Future Dream of MPT:

Solar Power Satellite (SPS)

1GW Solar Power Station

2kmf Solar Cells

2kmf Microwave Antenna

< 10,000 ton weight

36,000km

Wireless Power

Transmission

via Microwave

2kmf

Receiving Antenna

Energy Availability Factor

Ground PV

: < 15% (Night, Rain…)

Space PV (SPS)

: >90% (No Night in 36,000km Orbit,

No Rain by Microwave Propagation)

-> SPS is huge, stable, and CO2-less

Power Station

Power Density~350W/ /㎡at rectenna center

~10W/ /㎡at rectenna edge

WPT Ground Test

Microwave

Beam

MPT Experiment on Feb. 2015Thin-High Efficiency Phased Array with GaN MMIC

55m

2.5cm thickness phased array

GaN MMIC Amplifiers

5.8GHz, 1.8kW

Developed by Mistubishi Electric Corp. (Phased Array), IHI Aerospace (Rectenna Array), Supported by METI 20

Nobel winner Hiroshi Amano and his team tap gallium nitride technology in bid to transmit power wirelessly from a distance (2018)

21

https://www.japantimes.co.jp/news/2018/01/15/national/nobel-winner-hiroshi-amano-team-tap-

gallium-nitride-technology-bid-transmit-power-wirelessly-distance/#.Wl0yf2cUmUl

“Our first target is to create a wirelesssystem to supply electricity to drones withinthree years,” Amano said.

The team has begun by developing a systemfor drones. With the cooperation ofJapanese electronic manufacturers anddrone developers, they are currentlybuilding a system with an electric circuit andembedded antenna.

22

Wireless Power Transfervia Radio Waves

in Far Field

Transmitter

Transmitted

Power (Broad)

→ Electric

PowerOnly Carrier for WPT

Very Narrow

Frequency

Time and

Space

→ Electric

Power→ Electric

Power

Transmitter

Receiver

→Power

Time and Space

Information

Frequency

Wide

Electric Power

to UserReceiver

→Power

Transmitted

Power

Transmitted

Power

Transmitted

Power

t t

RF Amplifier Rectifier

(+ Antenna = Rectenna)

Transmitting

AntennaRF Choke

(DC Bias)

RF Choke

(DC Bias) DC

Block

VDD-VG

R０

Imp

ed

an

ce

Ma

tch

ing

Circ

uit (N

o

Lo

ss)

Impedance M

atc

hin

g

Circ

uit

or H

igher H

arm

onic

s

Resonato

rs

FET,

HEMT,

etc.

Imp

ed

an

ce

Ma

tch

ing

Circ

uit

an

d L

ow

Pa

ss

Filte

r

RL

DC

Block

Receiving

Antenna

Electromagnetic

ally

Uncoupled

Source

Impedance M

atc

hin

g

Circ

uit

or H

igher H

arm

onic

s

Resonato

rs

Diode

User

DC

I V I V I V I V I V I V

Wireless Power Transfer via Radio Waves

23

Field of Radio Waves

24

2

2

2

2

Dd

Dd

d

I : Reactive Near Field

II : Radiative Near Field (Fresnel Region)

III : Far Field (Fraunhofer Region)

[Antenna Element] [Aperture Antenna]

Electric Field from Aperture Antenna

in Near Field and Far Field

II : Radiative Near Field (Fresnel Region)

= Sphere Wave (Beam-type WPT)

III : Far Field (Fraunhofer Region)

= Plane Wave (approximation) (Ubiquitous WPT)

I : Reactive Near Field = Inductive WPT

25

Theoretical Beam Efficiency in Far Field (Plane Wave)

24 d

PP t

r

Simple Surface

Area of Sphere

Sourcet

rtr P

d

AGP

24

Friis Transmission

Equation

)(

02

)(

01

kztjkztj

x eEeEE

In far field (at long distance),

radio wave can be assumed as plane wave.

2224 d

AA

d

AG

P

P rtrt

t

r

Beam

Efficiency

Field of Radio Waves

26

2

2

2

2

Dd

Dd

d

I : Reactive Near Field

II : Radiative Near Field (Fresnel Region)

III : Far Field (Fraunhofer Region)

[Antenna Element] [Aperture Antenna]

Electric Field from Aperture Antenna

in Near Field and Far Field

II : Radiative Near Field (Fresnel Region)

= Sphere Wave (Beam-type WPT)

III : Far Field (Fraunhofer Region)

= Plane Wave (approximation) (Ubiquitous WPT)

I : Reactive Near Field = Inductive WPT

Measured Data in Near Field

27

mmD

mmD

421472

1224.0,3

2

@ Yamasaki,

Japan, 1996

28

Formula of Efficiency of WPT via Radiowavesfor Beam-type WPT (in Radiative Near Field)

t parameter

0 0.5 1 1.5 2 2.5 30

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

Tau

Eta

t

rrt

P

P

d

AA

e

22

2

2

1

t

t

t parameter and beam collection efficiency

•W. C. Brown, The history of power transmission by radio waves, IEEE Trans.

Microwave Theory and Techniques, MTT-32, pp.1230-1242, 1984.

t

Rt Rr

D

Antenna

ApertureRectenna

Aperture

‘

–3 –2 –1 0 1 2 30

2

4

–1 0 10

1

Radius

Electric Field on Tx Ant. Electric Field in Far Field.

Radius

Fraunhofer’s Diffraction (|r0|, |r| <<d)

00 rrr dvyuxd

kf

d

k

d

kdg

jexp )(

2

jexp

)exp(j)(

d:distance, At,r : effective area of Tx, Rx antenna

2t

Friis'

Formula

Near distance or

Higher frequencyFar distance or

Lower Frequency

d

29

Theoretical 100% Receiving Efficiency at Infinite Array

伊藤他, “磁流アンテナを用いたレクテナの受電効率”, 信学技報AP84-69, pp.9-14, 1984

xJxJxB

xJxJxB

akx

GZ

akD

dxBxBZ

akG

DG

GA

LL

A

m

p

rad

pmrad

d

rade

yx

e

20

20

0

0

2

0

2

0

222

0

2

0

2

sin

sincos4

4

cos

Gd : operating conductance of array with antenna

position in previous page

Grad : radiation conductance of one element

D : antenna gain of one element

Grad, D is only TM110 mode by Derneryd

A : equivalent radius of CMSA

V0 : suplly voltage

K0 : propagation constant in free space

[Theory of microstrip antenna (magnetic current antenna)]

Receiving Efficiency η

HFSS Simulation ResultC

ell n

um

ber

of

z ax

is

Cell number of y axis

𝐻x [A/m]

Cel

l nu

mb

er o

f z

axis

Cell number of y axis

Receiving Efficiency: 99.9%

Magnetic field distribution Reflected magnetic field distribution

（After 15 cycles of Plane Wave input）

ReflectorAntenna ReflectorAntenna

Yu Tsukamoto, et al. “Study on a Dipole Array Antenna with Reflector for Non-Leak MPT System to Vehicles”, Proc. of 2015 Asian Wireless Power Transfer Workshop, 14.pdf 30

RF Harvesting ScenariosTokyo, Atlanta and London

R. Vias, H. Nishimoto, M. Tentzeris, Y. Kawahara, T. Asami, “A Battery-Less, Energy Harvesting Device for Long Range Scavenging of Wireless Power from Terrestrial TV Broadcasts,” IEEE 2012 IMS Digest, Montreal, June 2012.

31

M. Pinuela, P. Mitcheson, S.

Lucyszyn, “Ambient RF Energy

Harvesting in Urban

and Semi-Urban Environments,”

IEEE T-MTT, July 2013.

Energy Harvesting from TV Tower Signal by Univ. of Tokyo and Georgia Inst. of Tech.

32

Battery-Free Cellphone (Univ. of Washington)

33V. Talla, et al., “Ba‚ttery-Free Cellphone”, Proc. of the ACM on Interactive, Mobile, Wearable and

Ubiquitous Technologies, Vol. 1, No. 2, Article 25. Publication date: June 2017.

Wireless-Powered ZigBee in Same Frequency Band

34

ON ONON

OFF OFF

ZigBee

Rectenna

Mic

row

ave P

ow

er

Zig

Be

e C

om

mu

nic

atio

n

Mic

row

ave P

ow

er

Zig

Be

e C

om

mu

nic

atio

n

Mic

row

ave P

ow

er

Zig

Be

e C

om

mu

nic

atio

n

Time

• We propose MPT-ZigBee system at

same frequency of MPT and ZigBee (at

2.45GHz) with scheduling algorism.

• We can increase a limit power without

any interference (5pW/cm2 (CW)

-> 1.91mW/cm2 (pulse, no scheduling)

- > 2.61mW/cm2 (pulse, scheduling)

Intermitted

(Pulse) MPTDevice Type

As join in network

As not join in network

End device 9.46 mW 61.8 mW

Ichihara, T, et al., “Study and Development of an Intermittent Microwave Power Transmission System for a ZigBee

Device”, Proc. of 2014 IEEE Wireless Power Transfer Conference (WPTc2014), 2014, pp.40-43

Wireless Power Transfer to IoT Sensors in Hospital

(Project of ‘Center of Innovation’ supported by JST)

35

Transmitter

(927MHz, 5W)

Receivers(Sensors)

Sensing Data

Present : 920MHz-band, <1W, >5m distance

Future in ‘special Region’

: 920MHz-band, <5W, >10m distance

by Kyoto University

with Panasonic co.

in 2015

Field Experiment of Battery-less Sensor with Organic IC (Kyoto Univ., Panasonic, and Yamagata Univ.)

36at Special Permitted WPT City (Area) in South of Kyoto (2017.12)

Commercial Products of WPT via Radio Waves

• Venture Companies of Wireless Charger of Smart Phone* ‘Cota’ by Ossia inc. (WiFi-Band) http://www.ossiainc.com/

* ‘Wattup’ by Energous corp. (2.45GHz and 5.8GHz Band)

http://www.energous.com/

• Japanese Company (Dengyo)of Battery-less Sensor

(900MHz-Band) http://www.den-gyo.com/solution/solution10_b.html

UHF Band Transmitter

(920 MHz Band)

Re

ctifyin

gC

ircuit

Tran

s-M

itter

Sensor &Micro Computer

A few m

Wireless Power

DataTransmission315 MHz Band

Wireless Sensor

37

KDDI (One of Big 3 mobile

phone company

in Japan) supports them.

Delegate of US of ITU

AirFuel Group

‘Uncoupled WPT’

Based on FCC-15

t t

RF Amplifier Rectifier

(+ Antenna = Rectenna)

Transmitting

AntennaRF Choke

(DC Bias)

RF Choke

(DC Bias) DC

Block

VDD-VG

R０

Imp

ed

an

ce

Ma

tch

ing

Circ

uit (N

o

Lo

ss)

Impedance M

atc

hin

g

Circ

uit

or H

igher H

arm

onic

s

Resonato

rs

FET,

HEMT,

etc.

Imp

ed

an

ce

Ma

tch

ing

Circ

uit

an

d L

ow

Pa

ss

Filte

r

RL

DC

Block

Receiving

Antenna

Electromagnetic

ally

Uncoupled

Source

Impedance M

atc

hin

g

Circ

uit

or H

igher H

arm

onic

s

Resonato

rs

Diode

User

DC

I V I V I V I V I V I V

Wireless Power Transfer via Radio Waves

38

39

Rectenna – Rectifying Antenna –Radio Wave -> DC Power Converter

Brown&JPL Rectenna

(2.45GHz) 1970-75

Rectenna by Hokkaido Univ.

(2.45GHz) 1984

Rectenna byTexas A&M Univ.

(35GHz) 1992

Rectenna

byDENSO co.

(21GHz) 1997 Commercial Rectenna by DENGYO co. (2.45GHz) 2011

Rectenna

by Kyoto Univ.

(5.8GHz) 2001

Rectenna by Intel co.

(674 - 680 MHz) 2009

antenna

diode

antenna

diodeantenna

diode(backside)

antenna

diode

Radio Wave

DCTo Load

Imp

ed

an

ce

Ma

tch

ing

Circ

uit

an

d L

ow

Pa

ss

Filte

r

RL

DC

Block

Impedance M

atc

hin

g

Circ

uit

or H

igher H

arm

onic

s

Resonato

rs

Diode

User

Receivable Wireless Power

Receivable Wireless Power [W]

= Power Density @ Receiver [W/m2]

which depends on Transmitter and Distance

x Antenna Aperture [m2]

which is related with antenna gain and Directivity

x Antenna Efficiency [%]

x Rectifier Efficiency [%]

(x Time Factor)

40

41

Rectifier1. Half Wave (Theoretically 50%)2. Full Wave (Theoretically 100%)3. Bridge (Theoretically 100%)4. Single Shunt (Theoretically 100%)5. Double Voltage6. Charge Pump etc.

C

λ /4 line

Diode

“Theoretically 100%”

is most important

for WPT and harvesting.

Like Class-F Amplifier

Frequency Characteristics of Efficiency of Rectenna

42

2.45GHz 5.8GHz 14GHz 24GHz 35GHz

100%

50%

0%

10GHz

60%

70%

80%

90%

40%

30%

20%

10%

100GHz45GHz 62GHz 72GHz

Frequency

RF-

DC

Co

nve

rsio

n E

ffic

ien

cy

: Diode : CMOS

antenna

diode

by Brown&JPL

(2.45GHz) 1970-75

by Texas A&M Univ.

(35GHz) 1992

Products by DENGYO co. (2.45GHz) 2011

by DENSO co.

(14GHz) 2000

MMIC by Kyoto Univ.

(24GHz) 2012

by École Polytechnique

Montréal (94GHz) 2015

antenna

diode

by Tel-Aviv University

(75-110GHz) 2014

532um x 910um

by Tsukuba Univ.

(94GHz) 2016

Input Poweror Connected Load

T.- W. Yoo and K. Chang, “Theoretical and Experimental Development of 10 and 35 GHz Rectennas”, IEEE Trans. MTT, Vol.40, No.6, 1992, pp.1259- 1266

Higher Order

Harmonics Effect

RF-DC conversion efficiency of rectifier

43

RF-DC conversion

efficiency

100%

V

I

VJ

(0.2-0.3V)

Vbr

(10-30V)

-VJ

Rdiode

“rectenna”region“detector”

region

VJ Effect

Vbr EffectDiode Maximum

Efficiency Curve

Maximum Eff. is

>90% at 2.45GHz

> 80% at 5.8GHz

How to increase efficiency of rectenna

• Choose theoretically 100% circuit

• Reduce number of diodes which include loss factor

– Recommend single shunt rectifier

• Choose diode with Low RC diode

• Match impedance at input and output

• Design circuit with higher harmonics combination (like class-F amplifier)

– Suppress higher harmonics re-radiation

• To add high voltage (almost breakdown)

• (Additionally) consider combination of antenna

44

Input Poweror Connected Load

T.- W. Yoo and K. Chang, “Theoretical and Experimental Development of 10 and 35 GHz Rectennas”, IEEE Trans. MTT, Vol.40, No.6, 1992, pp.1259- 1266

Higher Order

Harmonics Effect

RF-DC conversion efficiency of rectifier

45

RF-DC conversion

efficiency

100%

VJ Effect

Vbr EffectDiode Maximum

Efficiency Curve

Maximum Eff. is

>90% at 2.45GHz

> 80% at 5.8GHz

Low Power Rectenna – How to add high voltage at diode

• Charge Pump -> High Voltage but Low Efficiency

• Input Matching Network [e.g. Active] (MIT, US, 2015)

• Output Filter Matching (Kyoto Univ. etc., Japan)

- 50% @ 1mW, 5.8GHz (2004)

• Standing Wave by Reflection

(Okayama Univ., Japan, 2004)

• Rectifying Circuit with Resonator

(Tohoku Univ. (2006), Toyama Univ. (2013), Japan)

- 40% @ 100mW, 900MHz

• High Impedance Circuit and Antenna

(Kanazawa Inst. Tech. (2016), Japan)

- 40% @ 100mW, 900MHz

• Self-Biased Rectifier (Univ. of Cantabria, Spain, 2015)46

RISH, Kyoto Univ. 47

Toward New Radio Wave Regulation of WPT

47

ITU ActivitiesITU : International Telecommunication Union (Founded in 1865)

which cites the following purposes for the union: • to maintain and extend international cooperation between all members

of the union for the improvement and rational use of telecommunications of all kinds;

• to promote and to offer technical assistance to developing countries in the field of telecommunications;

• to promote the development of technical facilities and their efficient operation;

• to promote the extension of the benefits of the new telecommunication technologies to all the world's inhabitants;

• to harmonize the actions of members in the attainment of these ends; • to promote, at the international level, the adoption of a broader

approach to telecommunications issues, an approach that includes other world and regional organizations and nongovernmental organizations concerned with telecommunications.

48

Question Report Recommendation Regulation

Discussion Result is published as

Question ITU-R 210-3/1 (1997)Wireless power transmission

decides that the following information be gathered

1 What applications have been developed for use of WPTtechnologies?

2 What are the technical characteristics of the emission employed in or incidental to applications using WPT technologies?

3 What is the WPT’s standardization situation in the world?

decides that the following Questions should be studied

1 Under what category of spectrum use should administrations consider WPT: ISM, or other?

2 What radio frequency bands are most suitable for WPT?

3 What steps are required to ensure that radiocommunicationservices, including the radio astronomy service, are protected from WPT operations?

49

Discussion of WPT in ITU on June, 2016• Two Documents are submitted to ITU from Japan

– PROPOSED REVISION OF THE WORKING DOCUMENT TOWARDS A PRELIMINARY DRAFT NEW REPORT ITU-R SM.[WPT.BEAM]

-> Toward Draft New Report – WORK PLAN FOR WIRELESS POWER TRANSMISSION

VIA RADIO FREQUENCY BEAM-> For Discussion of Each Applications

• Following frequency bands are listed– 915MHz band (on ISM band except in region 2)– 2.45GHz-band (on ISM band)– 5.8GHz band (on ISM band)

50

Done!!!

“New Report” is published

from ITU Now!http://www.itu.int/pub/R-REP-SM.2392

Question Report Recommendation Regulation

Discussion of WPT in ITU on Nov., 2016

Meeting： ITU-R RG-WPT/WP1A/WP1BThere was no SG1 meeting and no formal approval of Report or Recommendation

Date： Nov. 22nd (Tue.), – Nov.20th (Wed.) , at ITU headquarter in GenevaResults：1) Discussion of role of WP1A and WP1B2) Toward Recommendation of 6.78MHz-band WPT・There was new proposal from Bosch about the other frequency for other WPT system. But it

was rejected because there was no impact study to the other wireless systems which must be.・There was document with concern about effect of 2nd harmonics from broadcasting company

and from radio astronomy

3) Discussion of EV-WPT・Drafting of revised ITU-R Report SM.2303-1 by new organization of DG-NON.BEAM under

WP1A was done.・Opinions of coexistence power level to AM radio both from WP6A/EBU and from Japan will be

on the above revised report to show there is the different approaches

4) Discussion of Beam WPT・DG-BEAM under WP1A revised work plan toward new report [WPT-BEAM.IMPACT] based on

documents from USA and Japan.

5) Proposal of new report “Frequency management method of WPT”・Toward WRC-19, frequency management method of WPT, e.g. spectrum category of EV-WPT

will be done. 6) Other topics : Safety Issue

• Discussion of safety issue of WPT, whether it is ITU matter of not. ICNIRP, IEEE, and the other safety standards are referred in WPT documents.

51

Work Plan for Wireless Power Transmission via Radio Frequency Beam

in ITU (International Telecommunication Union) (Revised on Nov., 2016)

52

Characteristics of beam WPT applications

Type

ID Applications Frequency band

Condition Distance Power Impact study

Remarks

a

a1Wireless PoweredSensor Network

915 MHz band,2.45 GHz band,5.8 GHz band

Indoor, outdoor Several meters –dozens of meters

< 50W Must

a2Wireless Charger ofMobile Devices

2.45 GHz band Indoor Several meters –dozens of meters

< 50W Must

b

b1Wireless PowerTransfer Sheet

2.45 GHz band In mesh-patternshielded sheet

Several meters(in sheet)

< 30W [N/A] ARIBSTD-T113

b2 MPT in Pipe 2.45 GHz band,5.8 GHz band

In shielded pipe 1 m – 100 m (inpipe)

< 50W N/A

b3Microwave Buildings 2.45 GHz band,

5.8 GHz bandIn shielded pipe 1 m – 100 m (in

pipe)50W –5kW

N/A

c

c1WPT to MovingFlying Target

2.45 GHz band,5.8 GHz band

Outdoor 10 m – 20 km 50W-1MW

Must

c2Point-to-Point WPT 2.45 GHz band,

5.8 GHz bandOutdoor 1 m – 20 km 100W –

1MWMust

c3Wireless Charging forElectric Vehicle

2.45 GHz band,5.8 GHz band

Outdoor 0.1-10 m 100W-100kW

Must

c4 Solar Power Satellite TBD Space to ground 36,000 km 1.3GW Must

Edited by USA, Japan, and Israel (based on Japanese Document)

Target Year of Each Application of Beam.WPT toward New Report [WPT-BEAM.IMPACT]

53

Target years of making reports ID Applications

[2017-2020] a1 Wireless Powered Sensor Network

[2017-2020] a2 Wireless Charger of Mobile Devices

[2017 – 2020

(Short Distance)]

[2020- 2030

(Long Distance)]

c2 Point-to-Point WPT

[2025-2030] c1 WPT to Moving Flying Target

[2025-2030] c3 Wireless Charging for Electric Vehicle

TBD c4 Solar Power Satellite

RISH, Kyoto Univ. 54

Introduction of Activities of WPT

in IEEE and IEICE

54

IEEE Wireless Power Transfer Conference (WPTc)

1st IMWS-IWPT (2011)2nd IMWS-IWPT (2012)at Kyoto, Japan

1st WPTC (2013)at Perugia, Italy

2nd WPTC (2014)at Jeju, Korea

55

4th WPTC (2016)at Aveiro, Portugal

5th WPTC (2017)at Taipei, Taiwan

6th WPTW (2018)at Montreal, Canada

3rd WPTC (2015)at Boulder, USA

History of IEEE WPTc (IMWS-IWPT)

• 2011@Japan paper 59/ 69 (88%) from 8 countries,

142 attendees (pre), 176 (total)

• 2012@Japan paper 60/ 68 (88%) from 7 countries,

117 attendees (pre), 146 (total)

• 2013@Italy paper 62/ 77 (80%)

90 attendees (pre)

• 2014@Korea paper 73/103 (71%) from 19 countries,

187 attendees (pre), 203 (total)

• 2015@USA paper 93/166 (53%) from 29 countries,

164 attendees (pre), 199 (total)

• 2016@Portugal paper 97/147 (66%) from 31 countries,

146 attendees (total)

• 2017@Taiwan paper 106/132 (81%) from 20 countries

169 attendees (pre) 56

IEEE Wireless Power Transfer Conference (WPTc2018)

Montreal, Canada, June 3-7, 2018

www.wptc-ieee.org

57

Important Dates:

Submission Deadline: February 18, 2018

Notification of Acceptance: March 12, 2018

Final Paper Submission: April 30, 2018

Conference Dates: June 3-7, 2018Accepted papers will appear in the WPTC-2018 conference proceedings and will

be submitted for publication in IEEE Xplore.

Contacts: WPTC organizing committee

Asian Wireless Power Transfer Workshop by IEICE

2015 @ Taipei, Taiwan

Paper 31

Attendees app.50

2016 @ Chengdu, China

Paper 44

Attendees app.100

2017 @ Singapore

Paper 60

Attendees app.70

58

2018 in Tokoku University, Sendai, Japan

3rd Asian Wireless Power Transfer Workshop (AWPT)

Dec. 9-11, 2017

@ National University of Singapore, Singapore

59

RISH, Kyoto Univ. 60

Conclusion

60

SPS

Buildings

Vehicles

Smart Energy

Communications –Power Coexistence

Energy Security

Infrastructure of Communications –Power Coexistence

Power Storage

Ubiquitous Power Source

Saving Energy

Our Dream : Wireless Power Society

Ubiquitous Power Source in Emergency

61

WPT Books

Wireless Power Transfer via Radiowaves (Wave Series)

by Naoki ShinoharaISTE Publishing &

John Wiley & Sons, Inc., UK & USA, 2014.1

ISBN 978-1-84821-605-1

Wireless Charging Technology and the Future of

Electric Transportationed. In-Soo Suh

(Chapter Writing)SAE Books, 2015.6

ISBN 978-0-7680-8153-4

Wireless Power Transfer Algorithms, Technologies

and Applications in Ad Hoc Communication Networks

ed. Sotiris Nikoletseas, Yuanyuan Yang, and Apostolos Georgiadis,

(Chapter Writing), Springer, 2016.7, ISBN 978-3-319-46810-5

+ 2 WPT books edited by Shinohara will be published next year (River Publisher, IET Books) 62