July, 2008 Project: IEEE P802.15 Working Group for Wireless Personal Area Networks N (WPANs( WPANs) Submission Title: Millimeter-wave Photonics for High Data Rate Wireless Communication Systems Date Submitted: July 2008 Source: Richard W. Ridgway, Battelle Address Voice: FAX: E-Mail: ridgway@battelle.org Re: Abstract: Millimeter-wave Photonics for High Data Rate Wireless Communication Systems Purpose: doc.: IEEE 802.15-08-0433-00-0thz 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. Submission 1
Millimeter-wave Photonics for High Data Rate Wireless Communication Systems Presentation to IEEE 802.15 THz Interest Group Richard W. Ridgway, Ph.D. Senior Research Leader Electronics and Avionics Systems July 16, 2008 ridgway@battelle.org 2
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 3
Integrated Optics at BattellePhotonics Three decades of Integrated Silica Toroidal Ring 2000 30 µm 1990 2000 PIRI is sold Battelle 2001 Optimer Photonics in Launched 2002 EO-Clad Silica Waveguides 2003 Modulator-Multiplexer 2005 mmw Communications Link 2006 World s Record for Wireless Transport 2007 Toroidal Sensors and Signal Processing 1991 Biorefractometer 1993 Grating Biosensor 1993 EO Spectrum Analyzer 1995 PIRI sells AWG 1980 1970 1982 AO Scanner 1983 EO Digital Correlator 1985 Microwave Sampler 1986 Pipelined Polynomial Processor 1987 PIRI is Launched 1989 94 GHz Optical Modulator 1976 Lithium Niobate Waveguides 1978 NASA Preprocessor in LN 4
Millimeter-wave Photonics 94 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. 100 G sample/second Sampler for Microwave Signals Ref: 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. 50 GHz Real-Time Spectrum Analyzer 94 GHz Beam Steering Antenna Ref: M.R. Seiler, R.W. Ridgway Studies of Millimeter-Wave Diffraction Devices and Materials Final Report, AFOSR, DTIC AD-A216 504, Dec 28, 1984 5
Millimeter-wave Communications 10 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. 6
Why Millimeter-waves? 1000 db/km 100 db/km H 2 O FOG Visibility 50 m 10 db/km O 2 H 2 O CO H 2 O H 2 O Heavy Rain (25 mm/hr) 1 db/km CO 2 H 2 O Drizzle (0.25 mm/hr) 0.1 db/km Millimeter Submillimeter Infrared Visible 10 GHz 100 GHz 1 THz 10 THz 100 THz 1000 THz 3 cm 3 mm 0.3 mm 30 µm 3 µm 0.3 µm Millimeter-wave frequencies offer good transmission through fog, clouds and rain 7
Why Millimeter-waves? 1000 Data Capacity (GB/s) 100 10 1 BPSK QPSK QAM16 QAM64 QAM128 0.1 0.1 1 10 100 1000 Carrier Frequency (GHz) Millimeter-wave frequencies can support large data capacities 8
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 system 6. 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. 9
mmw Signal Generation Frequency (wavelength) Domain λ 0 mmw Waveform Generator f f Laser Source λ λ AWG O/E mmw Detector Sideband Generator Optical Filter Modulator to Encode Signal Convert to Electrical Cassegrain antenna Time Domain Laser signal φ mmw modulated optical signal mmw modulated optical signal with encoded data mmw signal with encoded data Demodulated data signal Microwave Drive Electronics Data Generator 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. 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 10
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 11
Combining the Filtered Signals 1549.0 nm 1549.2 nm λ 1 2 3 4 5 6 7 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 12
Photo of Waveform Generator Modulator as Sideband Generator Modulator as Data Encoder Polarization Controllers Arrayed Waveguide Grating Diode Laser Source 13
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 14
Photonic Generation of Millimeter-waves 94 GHz 94 GHz λ 0 mmw Waveform Generator f Frequency (wavelength) Domain f λ Laser Source λ AWG O/E mmw Detector Sideband Generator Optical Filter Modulator to Encode Signal Convert to Electrical Cassegrain antenna Time Domain Laser signal φ mmw modulated optical signal mmw modulated optical signal with encoded data mmw signal with encoded data Demodulated data signal Data Rate = 10 GB/s Microwave Drive Electronics Data Generator F=15.4 GHz Battelle s IR&D Program is focused on the use of photonic components for the analog and digital modulation of millimeter-waves. 15
Millimeter-wave Photonics 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 Received Power (dbm) 10 5 0-5 -10-15 -20-25 -30 0 0.2 0.4 0.6 0.8 1 Distance (km) In August 2007, Battelle completed a field test to demonstrate 10 GB/s data transmission at 94 GHz. 16
Range Equations P receiver = P transmitter + G t + G r 20log 4π R λ mmw Antenna Gain Estimated Signal-to-Noise vs. Range Gain of Antenna (dbi) 90 80 70 60 50 40 30 20 Reasonably large antenna gains can be achieved over small areas!! 94 GHz 200 GHz 400 GHz 1 10 100 Diameter of Antenna (inches) Signal/Thermal Noise (db) 100 90 80 70 60 50 40 30 20 10 0 Reasonable S/Ns can be achieved out to 1 km 94 GHz 200 GHz 400 GHz 1 10 100 1000 10000 Range (m) 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. 17
Wireless Data Rates 18 Cell Phone 3G Distance 1 m 10 m 100 m 1 km 10 km 100 km DARPA Orcle DARPA ORCA WiFi (802.11b) Bluetooth WiMAX (802.16) Commercial mmw links Photonic-mmW Demonstration UWB (802.11n) 0.1 MB/s 1 MB/s 10 MB/s 100 MB/s 1 GB/s 10 GB/s 100 GB/s Data Rate
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 19
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 Dielectric waveguides confine the mm-wave signals in two dimensions 10 mw of modulated mm-wave signal at a carrier of 200 GHz is generated w/o mm- Wave amplifiers θ Angle scanning through Bragg diffraction (θ = +/- 20 ) Q Antenna module (2 x 2 ) is completely passive (No Heat!!) UTC Photodiodes to convert from optical domain to mm-wave domain Schottky-diode detection of mm-wave signals Photonic Approach for mm-wave Generation and modulation (5 GB/s data signal applied while in the optical domain) I mm-wave Bragg Diffraction for >35 db passive gain 5 GB/s Data In 5 GB/s Data Out Star 16 QAM 20
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 millimeterwave 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 21