This paper describes an optical spatial filtering velocimetry technique that converts an expanding or contracting speckle pattern into a photocurrent. This photocurrent will have a quasi-sinusoidal dependency on this specific speckle motion. The spatial filter consists of a series of concentric rings.
View Article and Find Full Text PDFIn this work, we present an analytic model for analyzing the range and frequency dependency of a monostatic coherent lidar measuring velocities of a diffuse target. The model of the signal power spectrum includes both the contribution from the optical system as well as the contribution from the time dependencies of the optical field. A specific coherent Doppler wind lidar system measuring wind velocity in the atmosphere is considered, in which a Gaussian field is transmitted through a simple telescope consisting of a lens and an aperture.
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