LIDAR Atmospheric Probe.
Abstract
All-weather operation of aircraft will require a means for measurement of glide slope visibility, especially at final approach. A brassboard device has been built for evaluation of the feasibility of eye-safe laser lidar measurement of slatn range visibility. A simple ratio measurement of the back-scattered energy from two ranges is used to infer atmospheric extinction coefficient, and therefore visibility. The laser source is a 1-kilowatt peak output optic-fiber coupled gallium arsenide laser array capable of operating at repetition rates to five kilohertz. The optical detector is a high-sensitivity silicon avalanche photo diode. The processor accepts range return from two selectable range distances, integrating the return, from each range distance, of a selectable number of laser pulses. Integration permits adequate signal-to-noise, even when using a relatively low-powered eye-safe laser. Since independent control is provided of the number of pulses to be integrated at each range distance, the return signal may be range-normalized. Integration is performed digitally. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1972
- Accession Number
- AD0907145
Entities
Organizations
- Sperry Corporation