UVC Airborne Holographic Lidar Transceiver

Marc Hammond, David Huish,Tom Wilkerson, Scott Cornelsen

Space Dynamics LaboratoryUtah State University

435-797-9611 tdw@sdl.usu.edu

presentation for theWind Lidar Working Group

Sedona, AZJanuary 27-29, 2004

Research supported by NPOESS/IPO, NASA, and SDL

© 2004

Outline

• High altitude aircraft : ER-2, Proteus

• Technology fusion basis (DLTA-M) HARLIE (Schwemmer), GLOW (Gentry)

• Performance

• UV– Cornerstone (UVC) transceiver

• UVC design progress at SDL

• Conclusion

Fusion of Two NASA Lidar Technologies

HARLIE

•Holographic scan Lidar•1064 nm (present)•Aerosol / cloud returnsas function of azimuth and

time•“Cross beam” winds

GLOW

•Doppler interferometer(“double-edge” etalon)•355 nm / 1064 nm Lidar•Line-of-sight windsfrom aerosol returns•LOS winds (molecular)from clear air

DLTA

•Holographic scan @ 355 nm•Multi-channel transceiver•LOS winds / Cross beam winds•Aerosol / Cloud morphology•Airborne and ruggedized•Platforms: ER-2 / Proteus•Cal / Val for space-borne wind lidar

Doppler LidarTechnologyAccelerator

DLTA Direct Detection DopplerLidar Instrument Layout

DopplerDetector

Non-DopplerDetector Laser

Rotatinghologram

LaserTransmission

Conical scans for high altitude HOE lidar

Nadir-45° sweep ( transonic) Tip-tilt mode

horizon

nadir

Expected performance-DLTA (nadir) Altitude 20 km

UVC-16: folded path, 16 in. hologram, 355 nm

Length, diam. 30 in.Weight 187 lbs.Optical eff. 6 %30 RPMPacific Scientific motorContitech timing belt

ASRC data systemHamamatsu PMT

SDL Transceiver Design

0 2 4 6 8 10 12 14 16 18 20

Range (km)

10-2

10-1

100

101

102

103

Photon Return (Number of Photons) 25ns

250ns

1000ns

Pulse energy 1 mJ 355 nm

Telescope diam. 40.6 cmObstruction diam 4.6 cmOptical efficiency 6 %

Horizontal path Clear airDensity 2.51019 cm-3

Range gate :

UVC-16 Performance Photon returns per pulse

Weight 107 lbs.Length, diam. 24“3-Rod truss

Convex secondaryExternal detectorOptical eff. 5%

Other details similar to UVC-16

UVC – 12 Compact Transceiver

UVC - 12

Optical Return Path

View from Detector End

Finite Element Analysis for UVC-12

Displacement Stress

Conclusion

• UVC is a compact, rugged transceiver for fusion of Holographic and Direct Detcction Doppler Lidar

• Thermal and Finite Element Analysis validate the design for flight in high altitude aircraft environment

• Next step: Vibration Analysis of UVC-16 and UVC-12

• Design and fabrication of optical instrumentation for aircraft and satellites a major activity at Space Dynamics Laboratory

• Next design direction: Composite construction for greater strength and savings in weight. Composite technology is a focus area for SDL and Utah State University