1. Ball Aerospace &
Technologies Corp.
OAWL Progress and Plans Christian J. Grund, Bob Pierce, Jim Howell, Miro Ostaszewski Ball Aerospace & Technologies Corp. (BATC), 1600 Commerce St. Boulder, CO Working Group on Space-based Lidar Winds Desdin, FL Jan. 28, 2009
Agility to Innovate, Strength to Deliver

2. Acknowledgements: The Ball OAWL Development Team
Jim Howell – Systems Engineer, Aircraft lidar specialist, field work specialist
Miro Ostaszewski – Mechanical Engineering
Dina Demara – Software Engineering
Michelle Stephens – Signal Processing, algorithms
Mike Lieber – Integrated system modeling
Chris Grund – PI system architecture, science/systems/algorithm guidance, electrical engineering
Carl Weimer – Space Lidar Consultant
No data or proprietary info
Ball Aerospace & Technologies

3. Optical Autocovariance Wind Lidar and the Integrated Direct Detection Wind Lidar Concepts

4. What is Optical Autocovariance Lidar?
Method:
Interferometric direct detection lidar
Instantaneous measurement of the phase and amplitude of the optical autocovariance function (OACF) about one Optical Path Difference (OPD)
Key Attributes:
Very high spectral resolution feasible
Self-referenced optical mixing
intensity measurements determine optical freq.
minimizes required electronic bandwidth
minimizes required signal processing power
Eliminates need to tune receiver to transmitter
Hardware-free compensation for LOS orbital V
Applications:
Doppler Lidar (wind profiles)
High Spectral Resolution Lidar (HSRL)
Differential Absorption Lidar (DIAL)
Ball Aerospace & Technologies

5. Optical Autocovariance Wind Lidar (OAWL)
The phase of the OACF for 0-velocity at 0-range is captured by locally sampling the outgoing pulse.
The OACF is measured for the atmospheric return from each range bin.
The wind velocity V is calculated from the difference in the OACF phase (Df) between the 0-velocity sample and each range return:
V = l *Df * c / (2 * OPD)
Df expressed as a fraction of 1 OACF period
Doppler Winds use the Phase of the OACF
Ball Aerospace & Technologies

6. Addressing the Decadal Survey 3D-Winds Mission with An Efficient Single-laser All Direct Detection Solution
Molecular WindsUpper atmosphere profile
Etalon Molecular Receiver
OAWL Aerosol Receiver
Combined Signal Processing
Telescope
Full Atmospheric Profile Data
Aerosol Winds
Lower atmosphere profile
UV Laser
HSRL Aer/mol mixing ratio
Most Efficient: Integrated Direct Detection (IDD) wind lidar approach:
Double-edge etalon strips and measures the molecular, rejects most of the aerosol component.
OAWL HSRL retrieval determines residual aerosol/molecular mixing ratio
Etalon processes molecular backscatter winds, corrected by HSRL from OAWL for aer/mol backscatter mixing ratio
Result:
single-laser transmitter, single wavelength system
single simple, low power and mass signal processor
full atmospheric profile using aerosol and molecular backscatter signals
OAWL alone can measure both, however power*aperture*precision optimization is less efficient (a trade)
Ball Aerospace patents pending
Previously approved
Top level description of a possible wind lidar architecture
Ball Aerospace & Technologies

7. OAWL Development Program

8. Optical Autocovariance Wind Lidar (OAWL) Development Program
Internal investment to develop the OAWL theory and implementable architecture, performance model, perform proof of concept experiments, and design and construct a flight path receiver prototype.
Recent NASA IIP win will take OAWL receiver at TRL-3, build into a robust lidar system, fly on the WB-57, exit at TRL-5.
No data or proprietary info
Ball Aerospace & Technologies

9. Ball Multi-wavelength OA Receiver
IRAD Status
Ball Aerospace & Technologies

10. OAWL IRAD Receiver Design Uses Polarization Multiplexing to Create 4 Interferometers in the Same space
Mach-Zehnder-like interferometer allows 100% light detection on 4 detectors
Cat’s-eyes field-widen and preserve interference parity allowing wide alignment tolerance, practical simple telescope optics
Receiver is achromatic, facilitating simultaneous multi-l operations (multi-mission capable: Winds + HSRL(aerosols) + DIAL(chemistry))
Very forgiving of telescope wavefront distortion saving cost, mass, enabling HOE optics for scanning and aerosol measurement
2 input ports facilitating 0-calibration
Recently shown publicly (6/08) at the ILRC and wind lidar WG (2/08). Identical to previously ITAR and IP approved.
Ball Aerospace & Technologies patents pending

11. Solid Model of Receiver (detector covers removed)
- All aluminum construction minimizes DT, cost
- Athermal interferometer design
- Factory-set operational alignment
for autonomous aircraft operation
- ≈100% opt. eff. to detector
- multi-l winds, plus HSRL and depolarization for
aerosol characterization
and ice/water cloud
discrimination
- Compatible with wind and HSRL measurements
Recently shown publicly (6/08) at the ILRC and wind lidar WG (2/08). Identical to previously ITAR and IP approved.
Detectors:
1 532nm depolarization
1 355nm depolarization
4 532nm winds/HSRL
4 355nm winds/HSRL
10 Total
Ball Aerospace & Technologies

12. OAWL Receiver Mechanical Components
A few simple components
Detector housings
Monolithic interferometer
Covers and base plate
mount to a monolithic base structure.
Detector amplifiers and thermal controls
are housed inside the base structure.
New material
Shows progress in receiver IRAD (that feeds into a recent NASA IIP awarded effort).
Identifies location of generic system components, but does not specify components.
Ball Aerospace & Technologies

13. Initial Static Interferometer Stability Tests
For these measurements the OAWL receiver is supported on the ends- worst case support scinario
Ball Aerospace & Technologies

14. All Aluminum Interferometer Supported by Ends no isolation, before/after repeated bolting and unbolting of the bottom plate
First tightening
2nd Tightening
Flat mirrors
Interferometer out
to TV Camera
Bottom access plate removal: fringe tilt returns with reinstallation of bottom – GOOD!
Static load: 2 kg suspended at center – no fringe shift or rotation - GOOD!
Thermal: ~1 fringe side drift /hr in unprotected laboratory environment – GOOD!
Ball Aerospace & Technologies

15. OAWL Receiver IRAD Progress Schedule and Status
Receiver Status (Ball internal funding):
Optical design PDR complete Sep. 2007
Receiver CDR complete Dec. 2007
Receiver performance modeled complete Jan. 2008
Design complete Mar. 2008
COTS Optics procurement complete Apr. 2008
Major component fabrication complete Jun. 2008
(IIP begins Jul )
Custom optics procurement vendor issues Aug. 2008
Custom optics procurement complete Dec. 2008
Assembly and Alignment in progress Jan. 2009
Preliminary testing scheduled Mar. 2009
Delivery to IIP scheduled Late Mar. 2009
Recently shown publicly (6/08) at the ILRC. Updated but otherwise identical in content to previously ITAR and IP approved slide.
Ball Aerospace & Technologies

16. OAWL System IIP and Status
Ball Aerospace & Technologies

17. OAWL IIP Objectives
Demonstrate OAWL wind profiling performance of a system designed to be directly scalable to a space-based direct detection DWL (i.e. to a system with a meter-class telescope 0.5J, 50 Hz laser, 0.5 m/s precision, with 250m resolution).
Raise TRL of OAWL technology to 5 through high altitude aircraft flight demonstrations.
Validate radiometric performance model as risk reduction for a flight design.
Demonstrate the robustness of the OAWL receiver fabrication and alignment methods against flight thermal and vibration environments.
Validate the integrated system model as risk reduction for a flight design.
Provide a technology roadmap to TRL7
No data, just a review of the objectives of the NASA IIP proposed work.
Ball Aerospace & Technologies

18. OAWL IIP Development Plan
Shake & Bake Receiver: Validate system design
Integrate the OAWL Receiver (Ball IRAD)
(entry TRL 3 (or 2.5 since the POC receiver uses same principles but is of a different architecture )
Into a lidar system
(add laser, telescope, frame,
data system, isolation, and
autonomous control software
in an environmental box)
Validate Concept, Design, and Wind Precision Performance Models from the NASA WB-57 aircraft
(exit TRL 5)
Ball Aerospace & Technologies

19. IIP System Concept for WB-57 Tests
Pallet Cover
6’ Pallet
(WB-57 form factor)
Custom Pallet-Mounting Frame
Telescope
IRAD - Receiver
New material
Conceptual drawing of a wind lidar suitable for deployment in aircraft for testing.
Laser Source
Custom Window
Ball Aerospace & Technologies

20. OAWL Validation Field Experiments
1. Ground-based-looking up
Side-by-side with the NOAA High Resolution Doppler Lidar (HRDL)
2. Airborne OAWL vs. Ground-based Wind Profilers and HRDL
(15 km altitude looking down along 45° slant path (to inside of turns).
Many meteorological and cloud conditions over land and water)
Fall 2009
Leg 1
Leg 2
Multipass
** Wind profilers in NOAA operational network
Platteville, CO
Boulder, CO
Houston, TX
Fall 2010
Ball Aerospace & Technologies

21. Taking an OAWL Lidar System Through TRL 5
NASA/ESTO Funded IIP Plan:
Program start, TRL 3 complete Jul
IRAD receiver delivered to IIP planned Mar. 2009
Receiver shake and bake (WB-57 level) assume 3/1/09 delivery Mar. 2009
System PDR/CDR planned Feb./Mar. 2009
Lidar system design/fab/integration design in progress Oct. 2009
Ground Tests completed planned Mar. 2010
Airborne tests complete (TRL-5) planned Dec. 2010
Receiver shake and bake 2 (launch level) planned Apr
tech road mapping (through TRL7) planned May 2011
IIP Complete planned June 2011
Recently shown publicly (6/08) at the ILRC. Updated but otherwise identical in content to previously ITAR and IP approved slide.
Ball Aerospace & Technologies

22. Conclusions
Optical Autocovariance Wind Lidar offers high performance wind measurements from aerosol backscatter at 355 nm.
OAWL aerosol and Double-edge Etalon molecular wind measurements can be made simultaneously and efficiently at 355nm.
IRAD Receiver: All components meeting required specs in house, final assembly/alignment in progress. Vendor performance issues overcome.
IIP in progress: OAWL Receiver TRL 2.5  OAWL system  Ground Tests
 Airborne Tests  TRL 5
Plan ground testing in late Fall 2009 along side NOAA Doppler lidar
Plan WB-57 flight tests in Fall 2010
Summarizes previous material, nothing new
Ball Aerospace & Technologies

23. Backups

24. Ball-internally funded Space-based OA Radiometric Performance Model – Model Parameters: Realistic Components and Atmosphere
LEO Model Parameters:
Wavelength nm, 532 nm
Pulse Energy mJ
Pulse rate Hz
Receiver diameter m (single beam)
LOS angle with vertical
Vector crossing angle
Horizontal resolution* km (500 shots)
System transmission
Alignment error mR average
(NOTE: ~50 mR allowed)
Background bandwidth pm
Orbit altitude km
Vertical resolution km, 250m
2-12 km, 500m
12-20 km, 1 km
Phenomenology CALIPSO model
Volume backscatter cross section at 355 nm (m-1sr-1)
Altitude (km)
Previously approved
Input assumptions for hypothetical performance predictions from space-based lidar
l-scaled validated CALIPSO Backscatter model used. (l-4 molecular, l-1.2 aerosol)
Model calculations validated against short range POC measurements.
Ball Aerospace & Technologies

25. OAWL – Space-based Performance: Daytime, OPD 1m, aerosol backscatter component, cloud free LOS
Threshold/Demo Mission Requirements
250 m
500 m
1km
Vertical Averaging (Resolution)
Objective Mission Requirements
New material
Latest hypothetical space prerformance predictions against customer given requirements, showing available margin
Similar to previously approved
Ball Aerospace & Technologies

26. Looking Down from the WB-57 (Daytime, 45°, 33s avg, 6600 shots)
Ball Aerospace & Technologies