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July, 2008

Project: IEEE P802.15 Working Group for Wireless Personal Area NProject: IEEE P802.15 Working Group for Wireless Personal Area Networks (etworks (WPANsWPANs))

Submission Title: Millimeter-wave Photonics for High Data Rate Wireless Communication Systems

Date Submitted: July 2008Source: Richard W. Ridgway, Battelle

Address Voice: FAX: E-Mail: ridgway@battelle.orgRe:

Abstract: Millimeter-wave Photonics for High Data Rate Wireless Communication Systems

Purpose:

Notice: 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 to 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.

doc.: IEEE 802.15-08-0433-00-0thz

Submission

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Millimeter-wave Photonics for High Data Rate Wireless Communication Systems

Presentation toIEEE 802.15 THz Interest Group

Richard W. Ridgway, Ph.D.Senior Research Leader

Electronics and Avionics SystemsJuly 16, 2008

ridgway@battelle.org

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Outline of Summary

• History of Integrated Optics at Battelle• Millimeter-wave Photonics• Understanding the Problem• Overview of System• System Performance• Field Test Results• Millimeter-wave Photonics Test Bed• The Battelle Development Team

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Integrated Optics at Battelle

1970

1980

1990

2000

1976 Lithium Niobate Waveguides1978 NASA Preprocessor in LN

1982 AO Scanner 1983 EO Digital Correlator1985 Microwave Sampler1986 Pipelined Polynomial Processor1987 PIRI is Launched1989 94 GHz Optical Modulator

2000 PIRI is sold2001 Optimer Photonics in Launched2002 EO-Clad Silica Waveguides2003 Modulator-Multiplexer2005 mmw Communications Link2006 World’s Record for Wireless Transport2007 Toroidal Sensors and Signal Processing

1991 Biorefractometer1993 Grating Biosensor1993 EO Spectrum Analyzer1995 PIRI sells AWG

Three decades of Integrated Photonics

30 µm

Silica Toroidal Ring

Battelle30 µm

Silica Toroidal Ring

Battelle

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Millimeter-wave Photonics94 GHz Electrooptic Modulator

Ref: Ridgway, et. al. Integrated optical modulator operating at millimeter-wave frequencies, IGWO Conference Paper MEE5-1, 1989.

5,015,052 Optical Modulation at Millimeter-Wave Frequencies, Issued May 14, 1991.

50 GHz Real-Time Spectrum Analyzer 94 GHz Beam Steering AntennaRef: M.R. Seiler, R.W. Ridgway “Studies of Millimeter-Wave Diffraction Devices

and Materials” Final Report, AFOSR, DTIC AD-A216 504, Dec 28, 1984

100 G sample/second Sampler for Microwave SignalsRef: R. Ridgway, et. al. “Spatial Sampler using Integrated Optic Techniques”, J. Lightwave Tech. VOL.LT-4,

No 10 Oct 1986

4,770,483 Electrooptic Sampling Apparatus for Sampling Electrical and Optical Signals, Issued Sept. 13, 1988.

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Millimeter-wave Communications10 Gb Ethernet - Wireless

10 Gb Ethernet on Fiber

Battelle has developed a method to transmit 10 Gb/s over a wireless link. The application allows the wireless transport of 10 Gb Ethernet at distances to 2-5 km.

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Why Millimeter-waves?

Drizzle (0.25 mm/hr)

Heavy Rain (25 mm/hr)

FOG Visibility 50 m

H2O

H2O

H2O

H2O

H2OCO2

CO

1000 dB/km

100 dB/km

10 dB/km

1 dB/km

0.1 dB/km

10 GHz 100 GHz 1 THz 10 THz 100 THz 1000 THz3 cm 3 mm 0.3 mm 30 µm 3 µm 0.3 µm

Millimeter Submillimeter Infrared Visible

O2

Drizzle (0.25 mm/hr)

Heavy Rain (25 mm/hr)

FOG Visibility 50 m

H2O

H2O

H2O

H2O

H2OCO2

CO

1000 dB/km

100 dB/km

10 dB/km

1 dB/km

0.1 dB/km

10 GHz 100 GHz 1 THz 10 THz 100 THz 1000 THz3 cm 3 mm 0.3 mm 30 µm 3 µm 0.3 µm

Millimeter Submillimeter Infrared Visible

O2

MillimeterMillimeter--wave frequencies offer good transmission through fog, clouds andwave frequencies offer good transmission through fog, clouds and rainrain

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Why Millimeter-waves?

MillimeterMillimeter--wave frequencies can support large data capacitieswave frequencies can support large data capacities

0.1

1

10

100

1000

0.1 1 10 100 1000

Carrier Frequency (GHz)

Dat

a C

apac

ity (G

B/s

)

BPSKQPSKQAM16QAM64QAM128

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Why Work in the Optical Domain?Advantages of Optical Approach:

1. Frequency Agile- mmW carrier can be varied for 35 GHz to 700 GHz from the same optical source. There are no millimeter-wave systems that have this

level of frequency agility.2. Signal Interconnections

- Optical interconnects are used throughout system, reducing loss and improving signal quality. With millimeter-wave systems, all interconnections will be either waveguide or cable. Both have higher loss than the equivalent optical interconnects.

3. Low Reflections Between Components– Optical interconnections have inherently low back reflections due to the excellent index match between the optical fibers and optical

waveguide components.

4. Antenna Remoting- Is accomplished with optical fibers to the photodiode

5. Phase Independent Amplification (PIA)- Optical amplifiers have significantly better PIA over millimeter-wave amplifiers

- This will improve the overall phase noise of the system6. Direct Modulation not possible at millimeter-waves

- There is no present means of modulating a millimeter-wave carrier directly at 10 Gb/s. Therefore, spectral efficient modulation approaches will be required.

7. Power Consumption- The electronic components needed to achieve 10 GB/s modulation on a millimeter-wave components will require at least 10x the power

needed for achieving the same modulation rate using the optical technique. 8. System Cost

- It is estimated that the component costs for achieving 10 GB/s using millimeter-wave components will be at least 10X higher than for the optical system achieving the same data rates.

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mmW Signal Generation

This block diagram outlines a wireless communication system capable of transmitting data in excess of 10 GB/s that uses an over-driven modulator to generate multiple sidebands. Various modulators, including lithium niobate and

electrooptic polymer modulators, have been used to generate sidebands and encode data.

Laser signal

Laser Source

O/E

∆f∆f

Sideband Generator Optical Filter Modulator to

Encode Signal Convert to Electrical

λ0

λλ

Time Domain

mmW modulated optical signal

mmW modulated optical signal with

encoded data

Frequency (wavelength) Domain

AWGAWG

mmW Waveform Generator

Microwave Drive Electronics

φ

Data Generator

mmW signal with encoded

data

Demodulated data signal

Cassegrainantenna

mmWDetector

Ref: 1) A. Hirata, M. Harada, and T. Nagatsuma, J. Lightw.Tech., Vol. 21, No. 10, Oct. 2003.2) R. Ridgway and D. Nippa, Photonics Tech. Let., Vol. 20, No. 8, April 15, 2008

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Lithium Niobate Modulators

• Fujitsu FT7912ER– Dual Drive 10 GB/s Modulator

– Specifications- Vπ (push-pull) = 2.6 volts @10 GHz- Optical Loss = 6.0 dB

– Measured- Vπ(push-pull) = 2 volts @DC- Vπ(push-pull) = 2.4 volts @500 MHz- Optical Loss = 5.25 dB

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Combining the Filtered Signals

1549.0 nm

1549.2 nm

1549.4 nm

1549..6 nm

1549.8 nm

1550.0 nm

1550.2 nm

1550.4 nm

1550.6 nm

1550.8 nm

1551.0 nm

25 GHz AWG

1

2

3

4

5

6

7

λ

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Photo of Waveform Generator

• Modulator as Sideband Generator

• Modulator as Data Encoder

• Polarization Controllers

• Arrayed Waveguide Grating

• Diode Laser Source

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Optical-to-mmW Conversion-UTC

• Uni-Traveling-Carrier Photodiode– Developed by NTT

– Technology: InP/InGaAs

– 3 dB Bandwidth = 310 GHz

– mmW Power Out at 100 GHz:- 20 mW (pulsed)- 6 mW (continuous)

– Efficiency- Input Optical = 20 mW- Output mmW = 3 mW (at 94 GHz)

UTC Photodiode

Optical In

mmW Out

DC Bias

Ref: H. Ito, et. al. , IEEE, J. Sel Topics Quantum Elec., Vol 10, No. 4, 2004

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Laser signal

Laser Source

O/E

∆f∆f

Sideband Generator Optical Filter Modulator to

Encode Signal Convert to Electrical

λ0

λλ

Time Domain

mmW modulated optical signal

mmW modulated optical signal with

encoded data

Frequency (wavelength) Domain

AWGAWG

mmW Waveform Generator

Microwave Drive Electronics

φ

Data Generator

mmW signal with encoded data

Demodulated data signal

Cassegrainantenna

mmWDetector

Laser signal

Laser Source

O/E

∆f∆f

Sideband Generator Optical Filter Modulator to

Encode Signal Convert to Electrical

λ0

λλ

Time Domain

mmW modulated optical signal

mmW modulated optical signal with

encoded data

Frequency (wavelength) Domain

AWGAWG

mmW Waveform Generator

Microwave Drive Electronics

φ

Data Generator

mmW signal with encoded data

Demodulated data signal

Cassegrainantenna

mmWDetector

Photonic Generation of Millimeter-waves

F=15.4 GHz

94 GHz

Data Rate = 10 GB/s

94 GHz

Battelle’s IR&D Program is focused on the use of photonic components for the analog and digital modulation of millimeter-waves.

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Millimeter-wave Photonics

-30-25-20-15-10

-505

10

0 0.2 0.4 0.6 0.8 1

Distance (km)

Rec

eive

d Po

wer

(dB

m)

In August 2007, Battelle completed a field test to demonstrate 10 GB/s data transmission at 94 GHz.

• Applications:– Wireless Data Transmission

- Data Rates to 12.5 GB/s- Analog signals to 10 GHz

– 10 GB Wireless Ethernet

• Status– mmW Carriers: 30 GHz - 350 GHz

– mmW Power: +3 dBm w/o amplification

– Data Rates: 5 GB/s – 12.5 GB/s

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Range Equations

⎥⎦

⎤⎢⎣

⎡−++=

mmwrtrtransmittereceiver

RGGPPλ

π4log20

It is estimated that the Cell-Phone sized transceiver can have a range of in excess of 1 km with a data rate of 5 GB/s.

Estimated Signal-to-Noise vs. Range

0102030405060708090

100

1 10 100 1000 10000

Range (m)

Sign

al/T

herm

al N

oise

(dB) 94 GHz

200 GHz400 GHz

Antenna Gain

20

30

40

50

60

70

80

90

1 10 100

Diameter of Antenna (inches)

Gai

n of

Ant

enna

(dB

i)

94 GHz200 GHz400 GHz

Reasonably large antenna gains can be achieved over

small areas!!

Reasonable S/Ns can be achieved out to 1 km

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Cell Phone 3G0.1 MB/s 1 MB/s 10 MB/s 100 MB/s 1 GB/s 10 GB/s 100 GB/s

1 m

10 m

100

m

1

km

1

0 km

100

km

Bluetooth

Dis

tanc

e

Data Rate

WiFi (802.11b)

WiMAX(802.16)

UWB(802.11n)

Com

mercial

mm

Wlinks

DA

RPA

O

rcle

DA

RPA

O

RC

A

Photonic-mm

W

Dem

onstration

Wireless Data Rates

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Millimeter-wave Photonics Test Bed

• Photonic Components– Fixed and Tunable 1550 nm lasers

– Arrayed Waveguide Gratings

– Electrooptic Modulators

– Optical Amplifiers

– Polarization Controllers

• Microwave Components– Frequency Sources

– Amplifiers

• Millimeter-wave Components– Waveguides, Couplers, Splitters

– Schottky Diode Detectors

– Low Noise Amplifiers

– Cassegrain and Horn Antennas

• Test Equipment– Agilent E8363B mmW Network Analyzer

– 12.5 Gb/s BERT

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Accomplishments and Path Forward• Battelle has developed a mmW communications link• Field Tests have confirmed operation out to 1 km• A Tri-Band System, operating at 35 GHz, 94 GHz and 140 GHz, has been

built and demonstrated in the lab.• Duplex Operation has been verified to 10 Gb/s• Plans for Further Development

– Consider Spectral Efficient Coding- QAM at millimeter-wave Frequencies

5 GB/s Data In

5 GB/s Data Out

mm-Wave Bragg Diffractionfor >35 dB passive gain

Photonic Approach for mm-Wave Generation and modulation (5 GB/s data signal

applied while in the optical domain)

UTC Photodiodes to convert from optical domain to mm-Wave domain

10 mW of modulated mm-Wave signalat a carrier of 200 GHz is generated w/o mm-

Wave amplifiers

Schottky-diode detection of mm-Wave signals

Dielectric waveguides confine the mm-Wave signals in two dimensions

Antenna module (2” x 2”) is completely passive (No Heat!!)

Angle scanning through Bragg diffraction (θ = +/- 20°)θ

5 GB/s Data In

5 GB/s Data Out

mm-Wave Bragg Diffractionfor >35 dB passive gain

Photonic Approach for mm-Wave Generation and modulation (5 GB/s data signal

applied while in the optical domain)

UTC Photodiodes to convert from optical domain to mm-Wave domain

10 mW of modulated mm-Wave signalat a carrier of 200 GHz is generated w/o mm-

Wave amplifiers

Schottky-diode detection of mm-Wave signals

Dielectric waveguides confine the mm-Wave signals in two dimensions

Antenna module (2” x 2”) is completely passive (No Heat!!)

Angle scanning through Bragg diffraction (θ = +/- 20°)θ

I

Star 16 QAM

Q

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The Battelle Development Team

• Principal Investigator: – Dr. Richard W. Ridgway

- Senior Research Leader at Battelle- 25 years of integrated optics and microwave

experience with lithium niobate, silica waveguides, and EO polymers.

- Architect of Battelle’s mm-Wave Photonics test bed.

- Ph.D. in Electrical Engineering (focus: communication theory)

- 21 U.S. Patents in integrated optical components for microwave and millimeter-wave applications

• Electronics and Avionics Systems– 220 engineers and support staff

– State-of-the-art clean room facility

– Fully equipped integrated optics test facility

– Microwave/mm-Wave laboratories and test equipment