Using a Solid-State Coherent Lidar for Precision Inflight Measurement of Turbulent Air Motion
Using a Solid-State Coherent Lidar for Precision
Inflight Measurement of Turbulent Air Motion
Coherent Technologies, Inc.
P.O. Box 7488
Boulder, CO 80306
Stephen M. Hannon (303-449-8736)
The objective of this project is to design an airborne, two-
micron pulsed, coherent, solid-state lidar system that can measure
time variations of the three-dimensional, atmospheric, turbulent
velocity components with a precision of 0.05 meters/second or
better. These measurements will be made at a point far enough from
the aircraft (10 meters or greater) to avoid disturbance.
Atmosphere aerosols or cloud droplets will provide the desired air
motion tracers, while simple conical scan of the optical-system
focal point, along a helical path traced out by the translation of
the aircraft, will be used to infer the instantaneous wind vector
along the flight path. Pulsing the laser provides high peak power
and enables a much higher signal-to-noise-ratio per pulse at
modest mean power. The speckle errors, which affect the velocity
precision at high signal-to-noise-ratios, are reduced in a focused
system because the illumination has a short depth of field. This
project will determine design parameters using detailed lidar
simulations and will conduct demonstration experiments using an
existing 2 śm pulsed, focused, coherent lidar system.
Potential Commercial Application:
Potential Commercial Applications: The principal application will
be for optical air-data systems for commercial and military
aircraft, particularly for on-board wind shear detection. The
three-dimensional wind field measurement capability will be useful
on research aircraft.