Remote measurement of wind speed using a dual beam backscatter laser Doppler velocimeter.

Measurements of atmospheric wind speeds at distances up to 60 m using a dual beam laser Doppler velocimeter with digital autocorrelation analysis, an unfocused argon ion laser (0.10-0.35 W) at 5145 A, and a 20-cm collecting telescope are reported. Criteria affecting the field performance of this system and an expression giving the power and range dependence of the data accumulation rate are presented. Major improvement of the system's performance can be made by focusing the laser beams and properly restricting the field of the collecting telescope. The potential of this technique for remote wind measurement at ranges of several hundred meters is discussed.