Ball Aerospace & Technologies Corp. OAWL Progress and Plans Christian J. Grund, Bob Pierce, Jim Howell, Miro Ostaszewski Ball Aerospace & Technologies Corp. (BATC), cgrund@ball.com 1600 Commerce St. Boulder, CO 80303 Working Group on Space-based Lidar Winds Desdin, FL Jan. 28, 2009 Agility to Innovate, Strength to Deliver

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

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

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

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

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 1011101100 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

OAWL Development Program

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

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

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

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

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

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

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

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. 2008) 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

OAWL System IIP and Status Ball Aerospace & Technologies

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

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

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

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

Taking an OAWL Lidar System Through TRL 5 NASA/ESTO Funded IIP Plan: Program start, TRL 3 complete Jul. 2008 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. 2011 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

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

Backups

Ball-internally funded Space-based OA Radiometric Performance Model – Model Parameters: Realistic Components and Atmosphere LEO Model Parameters: Wavelength 355 nm, 532 nm Pulse Energy 550 mJ Pulse rate 50 Hz Receiver diameter 1m (single beam) LOS angle with vertical 450 Vector crossing angle 900 Horizontal resolution* 70 km (500 shots) System transmission 0.35 Alignment error 5 mR average (NOTE: ~50 mR allowed) Background bandwidth 35 pm Orbit altitude 400 km Vertical resolution 0-2 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

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

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