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Kavaya – IIP-2004

Compact, Engineered, 2-Micron Coherent Doppler Wind Lidar Prototype:

A NASA IIP Selected Proposal

by

M. J. Kavaya, G. J. Koch, J. Yu, U. N. Singh, F. AmzajerdianNASA Langley Research Center

J. WangRaytheon Space and Airborne Systems

to

Working Group on Space-Based Lidar Winds28 June – 1 July, 2005

Welches, Oregon

Space and Airborne Systems

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Kavaya – IIP-2004

Key Personnel

• Dr. Michael J. Kavaya, LaRC, PI, coherent lidar• Dr. Grady J. Koch, LaRC, lidar system, field demonstration• Dr. Upendra N. Singh, LaRC, pulsed laser, requirements and priorities• Dr. Jirong Yu, LaRC, pulsed laser subsystem design and assembly• Dr. Farzin Amzajerdian, LaRC, coherent lidar systems• Dr. Jinxue Wang, RSAS, project management (currently Technical Director and Manager for Active Sensors at RSAS/SBRS)• Dr. David Rockwell, RSAS, solid-state laser design and modeling (laser expert)• Mr. Gerald Uyeno, RSAS, laser engineering (Technical Director for ABL-TILL and ATFLIR)• Dr. Richard Ackerman, RSAS, lidar systems engineering (laser/lidar system expert)• Mr. Steve Matthews, RSAS, laser engineering packaging (strong ABL-TILL and ATFLIR

experience)• Mr. Dan Nieuwsma, RSAS, laser engineering (strong ATFLIR experience)• Mr. Carl Nardell, RSAS, opto-mech design (currently Opto-Mech Department manager at

RSAS/SBRS)

Space and Airborne Systems

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Kavaya – IIP-2004

Relevant Events

1960 – laser demonstrated

1964 – CO2 laser demonstrated

1967 – CW CO2 laser wind measurement

1971 – airborne CW CO2 laser wind measurement

1977 – pulsed CO2 laser wind measurement

1984 – airborne pulsed CO2 laser wind measurement

1978 – first space feasibility study

(scheduled shuttle flight in 1983) 1988 – pulsed Nd:YAG laser wind measurement

1991 – pulsed Tm,Ho:YAG laser wind measurement

1994 – 2-micron pulsed laser reaches 100 mJ

1994 – airborne 2 micron pulsed laser wind measurement

1997 – 2-micron pulsed laser reaches 600 mJ

1999 – airborne CO2 pulsed laser winds with conical scan

2002 – begin NASA Laser Risk Reduction Program

2003 – 2-micron pulsed laser reaches 1000 mJ

2005 – selection of IIP winds proposals

1997-9 – SPARCLE

1998 – begin ADM

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Kavaya – IIP-2004

IIP Rationale

• Laboratory and airborne wind measurements have generated confidence in the coherent Doppler wind lidar (DWL) technique

• LaRC’s advancements of the 2-micron laser in pulse energy (20 – 1000 mJ, x50), diode pumping, pulse spectrum, beam quality, cooling, efficiency, etc. have generated confidence in the laser technology

• Emmitt’s investigations of the hybrid DWL concept for space have closed the huge gap between demonstrated and required laser and optics parameters, and have generated confidence in the mission feasibility

• Raytheon has delivered more than 30,000 compact and rugged lidar systems to the US military.

• Raytheon has strong heritage and experience in coherent LIDAR systems. Developed the first airborne coherent wind lidar using CO2 laser under contract to NASA Marshall Space Flight Center in the early 1970s.

• Raytheon has spent considerable IRAD resources to advance space DWL TRLs

• Compact, robust, space-qualifiable packaging of the LaRC laser technology is needed next to enable:

• Airborne demonstration of a coherent DWL as “close to space” as possible to enable:

• A credible proposal for a demonstration space mission to enable:• Operational DWL space satellite(s) for NPOESS

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Kavaya – IIP-2004

2 micron laser 1988

Hybrid ESSPUAV OperationHybrid Aircraft Operation

Compact Packaging

Space Qualif.

Pre-Launch Validation

Doppler Lidar Ground Demo.

Conductive Cooling Techn. 1999

Hybrid NPOESS

Autonomous Oper. Technol. Space

Qualif.Pre-Launch Validation

2-Micron Coherent Doppler Lidar

1-Micron Direct Doppler Lidar

Laser Risk Reduction Program

IIP-2004 Project

Past Funding

Diode Pump Technology 1993

Inj. Seeding Technology 1996

Autonomous Oper. Technol.

1 micron laser

Compact Packaging

Doppler Lidar Ground Demo.

Conductive Cooling Techn.

Diode Pump Technology

Inj. Seeding Technology

High Energy Technology 1997

High Energy Technology

Lifetime Validation

Lifetime Validation

7-Yr. Lifetime Validation

7-Yr. Lifetime Validation

1 micron altimetry space missions

2 micron Doppler wind aircraft flights

Pump Laser Diode Advancement

Dual Wavelength Telescope & Scanner Optional

Ground-Based Risk Reduction (IPO)

Simulation

Global Tropospheric Wind Profiles Example Roadmap

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Kavaya – IIP-2004

IIP Project Flow Diagram

RequirementsAnalysis

RequirementsAnalysis

RSAS

LaRC

System Design & Scaling

RequirementsList

Procurement

Review

Procurement

Opto-MechanicalDesign

Fabrication

IntegrationAnd Testing

Review

Field Testing

Space and Airborne Systems

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ABL-TILL: Track ILluminator Laser for ABL-TILL: Track ILluminator Laser for the Air Force AirBorne Laser Programthe Air Force AirBorne Laser Program

(a) ABL-TILL prototype at HRL (b) ABL-TILL after engineering and packaging at Raytheon SAS

Modular design to allow alignment and testing before integration Innovative transport optics design to tolerate wide ranges of diode output divergence Diode pumping is integrated with jet impingement cooling for laser rod thermal control Unique Robin Reeder birefringence compensation Compact diode relay optics Stray-light thermal shroud Reduction in mass and volume by a factor of 5 from lab. breadboard to packaged unit

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Space and Airborne Systems

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Compact Transceiver for ATFLIR Compact Transceiver for ATFLIR Targeting Pod on F/A-18 Targeting Pod on F/A-18

Compact and modular design & packaging. Total weight < 30 pounds. Currently in volume production at Raytheon. 500 to 1000 units in the next 10 years. Demonstrated superior performance and reliability under strong vibration and harsh environmental conditions with temperatures ranging from -54 to +71 oC. Deployment in harsh real combat environment (Iraqi Freedom and Enduring Freedom) where reliability is critical.

Transceiver Unit

Electronics Unit

F/A-18

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Space and Airborne Systems

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Kavaya – IIP-2004

Preliminary Development Flow Diagram

System Design & Scaling Raytheon laser/lidar models Modeling and scaling Optimization

Procurement Parts list and specifications Procurement etc

RequirementsAnalysis Flow-down from NASA LaRC ICD Envelope Mass Thermal Shock/vibe Future use Contamination Pressure etc.

Opto-MechDesign Mounts Package Alignment Plan

Fabrication

Assembly and Packaging

IntegrationAnd Testing

Supported by Raytheon IRAD

Airborne demonstration

Additional funding needed for airbornedemonstration

Supported by NASA IIP

Space

Cal/Val

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Space and Airborne Systems

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LaRC Capabilities

• Space-based atmospheric profiling lidar missions (LITE, CALIPSO)• Space-based wind mission design (LAWS, SPARCLE, GTWS,

ISAL/IMDC)• 2-micron pulsed laser design, development, optimization, record

pulse energy• Coherent (heterodyne) lidar (9-11 m CO2, 1 m, 2 m, 1.5 m)

• Coherent Doppler wind lidar systems (CO2, first 1 m, first 2 m)• Lidar field measurements (VALIDAR)• Laser Risk Reduction Program co-lead with GSFC• Laser/Lidar Technologies for Exploration co-lead with GSFC• Unique Lidar Intercomparison Facility (LIF)• Working Group on Space-Based Lidar Winds• Laser Diode Array Working Group, vice-chair

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Project Details

• Official start date is 10/1/05; 3 years duration• Will use LaRC’s Ho:Tm:LuLF solid-state 2-micron laser• Will begin with partially conductively cooled laser design (LDAs are

conductively cooled and the laser rod is liquid cooled). Packaged lidar may be upgraded to all conductively cooled in the future.

• Will package for aircraft operation with eye on space qualification needs

• Will try to accommodate interchangeable master oscillator modules to permit post-IIP “wind” and “CO2” interchangeable lidar modes

• Beyond IIP, will require telescope, scanner, and software for aircraft operation

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Conclusions

• We are confident in the Doppler wind lidar measurement technique and in the 2-micron laser technology

• The laser advances and the hybrid DWL concept for space has dramatically reduced the gap between the demonstrated and required laser and large optics

• Of the remaining tasks in the roadmap to space, packaging of the 2-micron lidar technology is a logical next step

• We are grateful for the previous NASA and IPO/NPOESS funding that has brought us to this point

• We are pleased that NASA has selected several wind related IIP proposals

• LaRC looks forward to working with partner RSAS on this IIP award, and is grateful for the internal funds that RSAS is contributing

Space and Airborne Systems