doc.: IEEE 802.15-15-10-0149-01-0thzMarch 2010

Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)

Submission Title: Towards 100-Gbit/s Wireless Using Terahertz WavesDate Submitted: 9 March, 2010Source: Tadao Nagatsuma*, Yuichi Kado, Company NTT (* also with Osaka University)Address [1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan]Voice:[+81-6-6850-6335], FAX: [+81-6-6850-6335], E-Mail:[nagatuma@ee.es.osaka-u.ac.jp]Re: IEEE 802 15 15 10 0149 00 0thRe: IEEE 802.15-15-10-0149-00-0thz

Abstract: Presentation of NTTs work towards 100-Gbit/s Wireless Using Terahertz Waves

Purpose: Information on development of future THz communication systemsPurpose: Information on development of future THz communication systemsNotice: This document has been prepared to assist the IEEE P802.15. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right j g y ( ) ( ) gto add, amend or withdraw material contained herein.Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.15.

Submission Tadao Nagatsuma, NTTSlide 1

Slide Slide 11

1 1 Graduate School of Engineering Science, Osaka UniversityGraduate School of Engineering Science, Osaka University22 NTT NTT MicrosystemMicrosystem Integration LaboratoriesIntegration Laboratories

Towards 100-Gbit/s Wireless Communications Using Terahertz Waves

65th IEEE 802.15 WPAN MEETING, THz-IG

Tadao Nagatsuma1,2 and Yuichi Kado2

March 15, 2010

Slide Slide 22

AcknowledgmentsAcknowledgments

A. Hirata (NTT), T. Kosugi (NTT), H. Takahashi (NTT), H.-J. Song (NTT), K. Ajito (NTT), M. Yaita (NTT), N. Kukutsu (NTT),

T. Ishibashi (NTT Electronics), H. Ito (Kitasato U.)

Y. Fujimoto (Osaka U.), K. Miyake (Osaka U.), K. Takada (Osaka U.), M. Kawamura (Osaka U.)

Fuji Television Network Inc, NHK (Japan Broadcasting Corporation)

Part of this work was supported by “The R&D Project for Expansion of Radio Spectrum Resources” of The Ministry of Information and Communications in Japan, and by “The Ministry of Education, Science, Sports and Culture, Grant-in-Aid for Scientific Research (A), 20246062, 2008”.

Members of Study Group on THz ICT at Kinki Bureau of Telecommunications in Ministry of Internal Affairs and Communications (MIC)

Slide Slide 33

Outline

Background & Needs 10-G wireless with 120-GHz Bands Exploring 300-400 GHz Band Summary

Slide Slide 44

Background & Needs 10-G wireless with 120-GHz Bands Exploring 300-400 GHz Band Summary

Slide Slide 55

GEPON

BPONFastE

GbE

10GbE

100GbEEthernet

PON(Passive Optical Network)

0.001

0.01

0.1

1

10

100

1000

1995 2000 2005 2010 2015 2020Year

Spe

ed (G

bit/s

)

10GEPON

~10 times / 5 years

Trends in Wired Communications Trends in Wired Communications

Slide Slide 66

802.11 802.11b

802.16(WiMAX Fixed)

802.16e(WiMAX Mobile)

802.15.3c

802.11g

802.11n

Ethernet Wireless LAN/PAN

0.001

0.01

0.1

1

10

100

1000

1995 2000 2005 2010 2015 2020Year

Spe

ed (

Gbi

t/s)

FWA/FPU

Wireless Backhaul

60 GHz

120 GHz

60 GHz

PON

Trends in Wireless Communications Trends in Wireless Communications

>300 GHz??

Slide Slide 77

Current Applications of 10-G Wireless

10GbE

Fixed Wireless Access

OC-192

Disaster recoveryDisaster recovery

Remote medical treatmentRemote medical treatment

Live relay broadcastof sports events

Live relay broadcastof sports events

Temporal Wireless Link

High-definition (HD) TVs

Slide Slide 88

Multi-Channel Transmission of Uncompressed HDTV Data

Urgent Needs in Broadcast

Wireless Wireless ““Last OneLast One--milemile””

HDTV Signals1.5 Gbit/s/camera

Optical fiber

Broadcast Van(Relay Point)

TV Broadcast Station

Relay PointEvent Site

Ch1

Ch2

Ch6

Slide Slide 99

Gigabit Wireless in Home Networks Gigabit Wireless in Home Networks Transmission of uncompressed HD (High Definition) data

Wireless HD: 3.8 Gbit/s with 60 GHzPanasonic “VIERA”, Sony “BRAVIA”

Wireless HD Interface (WHDI): 1.5 Gbit/s with 5 GHzSharp “AQUOS”

WiGig Alliance: 6 Gbit/s with 60 GHz

>1.5 Gbit/s

Blu-ray DVDHDTV

No cables, No connectors

Slide Slide 1010

Next Generation HDTV Next Generation HDTV ““UHDUHD””Super Hi-Vision (Ultrahigh Definition) TV by NHK, Japan

7680 x 4320 resolutionUncompressed video signal: ~24 Gbit/s

Digital Cimena-4K (4096x2160)

HDTV 1080p (1920x1080)

NTSC (720x480)

HDTV 720p (1280x720)

Super Hi-Vision /Ultra-High Definition Video(7680x4320)

horizontal angle of view:100 o

Slide Slide 1111

Giga-IR

4.48GHz: 560 Mbit/sUnder-70dBm/MHz (average)Corresponds to low-intensity radio wave regulation

Infrared light data communicationwith laser diode：1 Gbit/s

Close Proximity Wireless Transfer

Link Distance:10 mm to 100 mm

Difficulty in beam positioning

Slide Slide 1212

School

Hospital

Office

Highly-realistic sensation teleconference, telemedicine, remote-education

Elimination of bottlenecks in the speed of wired and wirelesscommunications in the core/access networks

4K-TVUHD-TV

4K-TV

4K-TV

Future Applications (1)

Slide Slide 1313

Increasing needs in instantaneous transfer of high-volume storage data in consumer devices as well as in medical equipments

SD memory*

40-100Gbit/s (5-12.5GB/s)Proximity link

SSD memory

HD video

*Tera-bite standardized at 2009

Future Applications (2)

Tera Bite Peta Bite

Cloud Server Download

Slide Slide 1414

Medical sensors

OS1 ApS1ApS2 Data ａ

Data ｂ Data ｃ

UHDTVcamera

4K-cinema,UHDTV

Telemedicine

Instantaneous Data Transfer

ＯＳ１

Data ａ Data ｂ

Data ｃ

ＯＳ２

ApS3 ApS4

Data ｄ

・・・

・・・

THz-waveAccess Point

THz-waveAccess Point

Optical Optical NetworkNetwork

Home

ApS1 ApS2

Business

Remote Robot Control

Outdoor・Disaster recovery・Live Broadcast

Indoor

Super-realityWireless Display

Wireless Cloud PC

3D Teleconference

Application Scene (THz ICT Study Group, Japan)

Slide Slide 1515

Towards 100 Gbit/s Wireless

Multi-value modulation at 60 GHz

Free-space optics (Infrared light)with WDM

Use of “terahertz” carrier frequencywith simple modulation format (ASK)

Not yet allocated for specific use at >275 GHz !!!

Slide Slide 1616

Dat

a R

ate

(Gbi

t/s)

10-1

1

10

1 10 100Carrier frequency (GHz)

10-2

10-3

50

5003G

Wireless LAN

Fixed wireless (p-p)

3.5G

WiMAX

Mobile phones

ＦＰＵ

Wireless Data Rate vs. Carrier FrequencyWireless Data Rate vs. Carrier Frequency

Slide Slide 1717

1

10

102

103

104

105

0.1

106

100 200 300 500 1000 2000 3000

1 dB/10 m

Frequency (GHz)

Atte

nuat

ion

(dB

/km

)Atmospheric AttenuationAtmospheric Attenuation

Appropriate for100 m~1 kmtransmission

Future use

Slide Slide 1818

15nm InAlAs/InGaAs MHEMT

ft fmax(GHz) (GHz)

610 305

45nm SOI CMOS 485(NFET)345(PFET)

-

670(480) 350(420)

385 >1000

GaAsSb/InP DHBT

50nm InP HEMT#

Transistor Technology

35nm InP HEMT## 480 1200

## Amplifier:13-15 dB Gain @300-345 GHz

# Amplifier:12 dB Gain @335 GHz

Progress in Transistors and ICsProgress in Transistors and ICs

Slide Slide 1919Frequency (GHz)

Progress in Electronic Oscillators

InP HBT

InP HEMT

CMOS(20nW)

SiGe HBT

CMOS

100 200 300 400 500 600

0

-10

-20

-30

-40

-50

Out

put P

ower

(dB

m)

RTD10 W

Slide Slide 2020

Laser Pointer USB

300GHzHorn Antenna

Like “IrDA” Module!

Small Antennas

120GHz Yagi-Uda Antenna

0.5 mm

0.5 mm

120GHz Patch Antenna

For GPSFor TV

300-500 GHz

+ MEMS & Metamaterials

Slide Slide 2121

Background & Needs 10-G wireless with 120-GHz Bands Exploring 300-400 GHz Band Summary

Slide Slide 2222

Millimeter-Wave Region(30GHz - 300 GHz)

10 100 10000.01

0.1

1

10

100

Frequency (GHz)

Atte

nuat

ion

Con

stan

t (dB

/km

)

H2O

H2O

4 20 40 200 400

O2 O2

H2O

120-160G

220-320G

75-100G

Choice of Radio-Waves: 120-GHz Band

Dry Air

Fog0.1g/m3

Usual Rain(a few mm/hr)

350-430G

Slide Slide 2323

Approaches: Electronics vs. PhotonicsApproaches: Electronics vs. Photonics

ElectricalRF signalgenerator

“Electronics” based Tx

THz wave

DATA signalAmplifier

Optical RF signalgenerator

Opticalmodulator

Optical signalElectrical signal

DATA signal

“Photonics (O/E)” based Tx

>1 THz >100 Gbit/s >1 THz

O/Econverter

>300 GHz

< 500 GHz <300 GHz

Electricalmodulator

< 40 Gbit/s

Coax/Waveguide

Amplifier

THz wave

Slide Slide 2424

・Output power： 10 mW, ～2 km・Power consumption: 600W

Receiver

Transmitter Transmitter Core

Photonic MMWGenerator

Data Modulator

・Output power： 10 mW, 2.2 km・Power consumption： 60 W

Mobility, PortabilityMobility, Portability

ControllerTransmitterTransmitter

2008/5

Easy set-up system(NTT Technical Review, vol. 7, no. 3, Mar. 2009)

2000-2002

Volume: 1/6Weight: 1/2

2004/7 2005/8

2007/1

Hardware Evolution in 10 years

Battery operationBattery operation

Photonics-based Transmitter

Electronics-based Transmitter

Slide Slide 2525

120-GHz-band System with Photonic Tx

A. Hirata et al., IEEE Trans. Microwave Theory Tech., Vol. 54, pp. 1937-1944, 2006.

Optical signalElectrical signal

125 GHzOptical signal

Data signal(10 Gbit/s)

Basebandamplifier

Basebandamplifier

IN

OUT

125 GHz MMW signal

Opticalmodulator

Data signal(10 Gbit/s)

Optical MMW signal

generator

PD w/o orw/ amplifier Receiver

Slide Slide 2626

f0

RFNf0

Nf0

DCPassively

mode-locked laser

Laser diodeDC

Laser diodeDCCoupler

(Combiner)

Heterodyning two lasers~10 THz

Actively mode-locked laser~300 GHz

Passively mode-locked laser~1 THz

Activelymode-locked

laser

Optical MMW/THz Carrier Generators (1)Optical MMW/THz Carrier Generators (1)

Slide Slide 2727

Optical MMW/THz Carrier Generators (2)Optical MMW/THz Carrier Generators (2)

Wavelength

f0 Nf0

Wavelength

Optical frequency comb generator

(OFCG)“multi-wavelength source”

Nf0Opticalfilter

f0

RF

Phase mod. Intensity mod. Single-mode laser

f0

f0

Example of OFCG

Continuously tunableand stable

Slide Slide 2828

HighHigh--Power OPower O--E Converter E Converter ““UTCUTC--PDPD””

InP

Back Illumination

AR Coating

n-ohmicContact

V.B. C.B.

Electron

Hole

p-ohmic Contact

Diffusion Block Layer

Light Absorption Layer(p-InGaAs)

Carrier Collection Layer (n-InP)

Layer StructureLayer Structure Band DiagramBand Diagram

UTC-PD: Uni-Traveling-Carrier-Photodiode

Slide Slide 2929

Output Power from UTCOutput Power from UTC--PDsPDs

10 -3

10 -1

10 1

10 3

10 5

0.1 1

Max

imum

det

ecte

d po

wer

(W

)

Frequency (THz)

f -4

LT-GaAs

20 dB

pin PD

NTTUTC-PD(resonant)4)

1)

3)

4)0.3 0.5

UCLUTC-PD

(resonant)3)NTT

UTC-PD(resonant)2)

NTTUTC-PD

(wideband)1)

2)

Slide Slide 3030

120120--GHz EmitterGHz Emitter

Optical Fiber

Optical SignalSlot Antenna(774 x 95 mm2) PD Chip

Si-Lens

Antenna

Si Platform MMW Signal1 mm

Microwave Photonics 2000

Slide Slide 3131

120120--GHz Receiver for 10GHz Receiver for 10--Gbit/sGbit/s

Slot Ring Antenna

MMW SignalSchottky Barrier Diode Chip (InP)

Filter

Si-Lens

IF DataSignal

Si Platform

1 mm

IF Data

Slide Slide 3232

Antennas for Long Distance LinkAntennas for Long Distance Link

Lens Antenna

Feed Horn

Sub-THz

Dielectric Lens

0.2 m

Hyperbolic Subreflector

Parabolic Reflector

Feed Horn

Cassegrain Antenna

Slide Slide 3333

H. Ito et al., Electron. H. Ito et al., Electron. LettLett., 41, pp. 360., 41, pp. 360--362, 2005.362, 2005.

Output

Optical Input

(125GHz,10 Gbit/s)

OpticalInput

Output

0.5 mm

MSL Amplifier UTC-PD

DC Bias

120120--GHz Emitter for Long LinkGHz Emitter for Long Link

Hybrid integration with butt-joint structure

Slide Slide 3434

Demodulator(Schottky Barrier Diode)Pre-Amplifiers

From Antenna(125 GHz)

Data Output(10 Gbit/s)

MMIC

Packaged Module

Input Output

120120--GHz Receiver for Long LinkGHz Receiver for Long Link

Monolithic IC Receiver

Slide Slide 3535

0.1-m-gate InAlAs/InGaAs HEMT gm = 1.2 S/mm, ft = 170 GHz, fmax = 350 GHz MIM capacitor, double-layer interconnection process

with BCB

BCB

SiN/SiO2

0.1 m

Fully matured production level technology (NTT Electronics)

Electronic Devices: Electronic Devices: InPInP HEMTHEMT

Slide Slide 3636

Antenna (45-cm diameter)

Optical signal generator

Optical modulator andcontrol board

PD with amplifier

120-GHz Band Transmitter

A. Hirata et al., IEEE Trans. Microwave Theory Tech., vol. 54, pp.1937-1944, 2006.

Slide Slide 3737

Lab

ReceiverFiber：400 m

Air transmission：250 m

Fiber：50 m

Transmitter

Setup for Field Test

digital

analog

A. Hirata et al., IEEE J. Lightwave Tech., vol. 26, no. 15, pp. 2338-2344, 2008.

Slide Slide 3838

Transmission Characteristics

5X105X10--1414131333rdrd dayday

2X102X10--14145522ndnd dayday

1X101X10--14143311stst dayday

BERBERTotal Total

number of number of bit errorsbit errors

Fluctuations in received power: < 1 dB for 6 hours

BER of wireless link: < 1X10-13

-30

-29

-28

-27

Rec

eive

d po

wer

(dB

m)

Time11:00 12:00 13:00 14:00 15:00 16:00 17:00

Receiver power Bit error rate (BER)

Meets OC-192 and 10GbE standardsA. Hirata et al., IEEE J. Lightwave Tech., vol. 26, No. 15, pp. 2338-2344, 2008.

Slide Slide 3939

Multiplexed HDTV Wireless Transmission System

10GbE

Transmitter

O/E

Receiver

10GbE Switch10GbE

10GbE Switch

10GbE

120-GHz -bandMMW wireless link E/O

HD Camera HD Monitor

i-Visto i-Visto i-Visto i-Visto i-Visto i-Visto

• “i-Visto gateway” converts two HDTV video streams into IP packets and then multiplexes the packets using the 10 Gigabit Ethernet protocol.

• Packets from three i-Visto are multiplexed by a 10GbE switch.• Six channels of HDTV signals are transmitted as 10GbE signals

over the 120-GHz-band wireless link.

NTT Technical Review, vol. 4, no. 3, pp. 64-70, 2006.

Slide Slide 4040

Control Unit(Optical Signal

Source)

Amp. PD

1:125 GHz(10Gb/s)TransmitterWDMFilter

2:90 GHz(5Gb/s)

3:30 GHz(1Gb/s)

Atte

nuat

ion

Con

st. (

dB/k

m)

10 100 1000Frequency (GHz)

H2O

H2O

20 40 200 400

O2 O2

H2O

110-150 GHz

75-100 GHz

30-40GHz

0.01

0.1

1

10

100

Multi-band System with Optical WDM

WDMSignal

Slide Slide 4141

XFP module(O/E)

DA

TA IN

Transmitter module

to antenna

Optical data (10-Gbit/s)

LO:15.625 GHz

Power amp. module

Transmitter MMIC

Multiplier(x4) MMIC

120 GHz with WR-8 waveguide (1 mW)

120 GHz with WR-8 waveguide

(10 mW)

LO:62.5GHz

Power amp.MMIC

LO signal IN

DATA IN

120-GHz-band Transmitter with Electronics

Battery operated

NTT Technical Journal, Vol. 19, No. 5, pp. 48–51, 2007 (in Japanese).

Slide Slide 424242

1010--Gbit/sGbit/selectrical signalelectrical signal

Cassegrain anntena

WaveguideWaveguide （（2 mm2 mm××1 mm)1 mm)

Bayonet mechanismBayonet mechanism

1010--Gbit/sGbit/soptical signaloptical signal

HDHD--SDI signalSDI signal

100100～～240 V AC240 V AC

Controller

PA module

15.625 GHz

Transmitter head

Txmodule

E/O

AC/DCController

O/E

Power supply

Controller

XFP

Camera cable( ~1km )

Controller Tx Frontend

Advanced All-Electronics System

NTT Technical Review, vol. 7, no. 3, Mar. 2009

Slide Slide 4343

-45 -40 -35

10-2B

it E

rror

Rat

e

Received Power (dBm)

10-4

10-6

10-8

10-10

10-12

Data rate:10.3125 Gbit/s

Minimum receivedpower: -38 dBm

Typical Performance

Slide Slide 4444

120 GHz-band link(distance 1 km)

InternationalBroadcast

Center

RF Tower

Specially built live-broadcast studio

(Beijing Media Center)

Beijing Olympic Park

Water Cube

Bird’s Nest

Fuji TV booth

Fuji TV (Japan)

Trials at Olympics: Configuration

TV programs with 120-GHz system

8/1 5 10 15 20 24

1

6

12

18

24Date

Tim

eof

day

NTT Technical Review, vol. 7, no. 3, Mar. 2009.

Slide Slide 4545

Trials at Olympics: Live-broadcasting

Fluctuations in received power (August 8, opening day of Olympics)

< 2dB

-31

-30

-29

-28

4 8 12 16 20 24

Rec

eive

d po

wer

(dB

m)

Time (hr)NTT Technical Review, vol. 7, no. 3, Mar. 2009.

Slide Slide 4646

Background & Needs 10-G wireless with 120-GHz Bands Exploring 300-400 GHz Band Summary

Slide Slide 4747

1 10 100 10000.01

0.1

10

100D

ata

Rat

e (G

bit/s

)

Carrier Frequency (GHz)

UWB@ 3-5 GHz

CMOS15 Gbit/s, 1m

@60 GHz

NTT-NHK10 Gbit/s, 3km

@120 GHz

1

Max. Data ratewith ASK in 10%-BW

Carrier Frequency vs. Data RateCarrier Frequency vs. Data Rate

Target

300-400 GHz

Slide Slide 4848

Objective ofObjective of 300300--GHz Band Wireless GHz Band Wireless

Examine “giga-bit” wireless link using full 300-400 GHz band

Photonics-based transmitter as technology demonstrator

Discuss possibility of >20-40 Gbit/s wireless

T. Nagatsuma et al., Tech. Dig. 2009 International Topical Meeting onMicrowave Photonics, 15 October, Session Th.2.

Slide Slide 4949

>40 GHz(24 Gbit/s)

>70 GHz(43 Gbit/s)

Pow

er

(a) Ultra-broadband channel

Carrier

2.5 GHz(1.5 Gbit/s)

Frequency

Pow

er

(b) Multiple giga-bit channels

Carrier

Possible Utilization of 300-400 GHz

UHD OC-768 HDTV

Slide Slide 5050

Oscillo-scope

Optical Amplifier

SBD

Optical Modulator

UTC-PDTerahertz Wave

Pulse-Pattern Generator

Wavelength-Tunable Laser

Wavelength-Tunable Laser

Horn AntennaPre-Amplifier

Limiting Amplifier

Bit ErrorDetector

Dielectric Lens

Transmitter Receiver

Experimental Wireless Link

Optical frequency

Optical frequency

1 0 1 1 0 0 1

f

fRadio frequency

2

1

IF frequency

IF frequency

Slide Slide 5151

p-dopedabsorption layer

un-dopedcollectionlayer

n-contactlayer

p-contactlayer

diffusion block layer

(C.B.)

(V.B.)

200 300 400 500 600Frequency (GHz)

0

-5

-10

-15

-20

-25

un-dopedabsorption layer

Out

put p

ower

(dB

m) 500 W @20 mA

Modified UTC-PD (Composite Structure)

A. Wakatsuki et al.,IRMMW-THz 2008.

Slide Slide 5252

p

i (InGaAs)n

(b) Conventional pin

non-absorbedi (InP)

(a) Dual depletion pin

i (InGaAs)

p

n

p-dopedabsorber

(p-InGaAs)

non-absorbed

(c) UTC

i (InP)hole

electron

Light

i (InGaAs)non-

absorbed

(e) Modified UTC (composite)

i (InP)

(d) Partially doped absorber

n-dopedabsorber

(n-InGaAs)

p-dopedabsorber

(p-InGaAs)Light

Menu of “Hamburgers”

Slide Slide 5353

0

20

40

60

80

100

120

260 300 340 380 420

6 mA

10 mA

Frequency (GHz)

Det

ecte

d P

ower

(W

)Output Power at 300-400 GHz

270-410 GHz

Slide Slide 5454

Horn Antenna

Optical Fiber

PD Module

Dielectric Lens

Photo of Transmitter

Slide Slide 5555

-15

-10

-5

0

5

10

15

0 400 800 1200 1600Frequency (MHz)

Rel

ativ

e R

espo

nse

(dB

)

Receiver Bandwidth

WR2.8ZBD, Virginia Diode Inc.

300 MHz @-3dB

800 MHz @-10dB

Slide Slide 5656

250 ps

2 Gbit/s

0 2 4 6 8 101E-12

1E-10

1E-8

1E-6

1E-4

0.01

BE

R

Photocurrent (mA)

Transmission Characteristics (1)

10 WTx Power

Distance: 50-100 cm

>20 Gbit/swith >100 W

Slide Slide 5757

280 GHz 300 GHz

320 GHz 340 GHz

360 GHz 380 GHz

400 GHz

(a) (b)

(c) (d)

(e) (f)

(g)

500 ps

Transmission Characteristics (2)

1 Gbit/s

40 ch. x 1 Gbit/swith 200 W

Slide Slide 5858

IF (low-pass) filter Diode

Slot-ring Antenna

Receiver Chip

Hemispherical Silicon Lens

Module

250-GHz Wireless Link with Integrated ReceiverH-.J. Song et al, IEE Electron. Lett., vol. 45, no. 22, October 2009.

Increasing Bit Rate (1)

(1.5 x 2 mm2)

Slide Slide 5959

0.01 0.1 1 10-12

-9

-6

-3

0

3

Rel

ativ

e R

espo

nse

(dB

)

IF Frequency (GHz)

CommercialDetector

BE

RPhotocurrent (mA)

2 4 6 8 10 12-12

-10

-8

-6

-4

-2(100ps/div)

8 Gbit/s

Integrated Detector

Increasing Bit Rate (2)

10 WTx Power

IF Bandwidth: ~4.5 GHz

250 GHz

Slide Slide 6060

SummarySummary

Established 120-GHz band system with 10-Gbit/s

First demonstration of giga-bit wireless at 300-400 GHz band using photonics-based transmitter

Error-free transmission at 1-Gbit/s from 280 to 400 GHz

Max rate (2 Gbit/s) was limited mainly by bandwidth of receiver

>20 Gbit/s is feasible by increasing a receiver IF bandwidth with the same photonics-based transmitter