Method and apparatus for remote measurement of variation in wind velocity

A method of measuring the variation in velocity of wind at a specific location, including steps of:

• transmitting a signal toward the zone at which wind movement is to be measured and detecting scattering of the signal in the zone resulting from wind movement in the zone along each of a plurality of paths;
• for each path, producing a doppler frequency component of the scattered signal;
• for each path, producing a spectrum of the doppler frequency components averaged over a first period of time;
• and
• for each path, calculating the second moment of the spectrum to produce an output measuring the variations of each component of the velocity of the wind along the path at the zone in a second time period substantially shorter than said first time period.

In a system for measuring variations in velocity of wind at a specific location, the combination of:

• transmitter means for directing a signal toward a zone spaced from said transmitter;
• a plurality of receivers for said transmitter means and spaced from each other, with each receiver directed toward said zone for receiving portions of the transmitter signal scattered in said zone and providing a receiver output having a doppler frequency component;
• a spectrum analyzer for each receiver output and providing as an output a spectrum of the receiver output signal averaged over a first time period;
• and
• first means for calculating the second moment of each of said spectra for generating an output signal for each spectrum as a measure of the variations in each component of the velocity of the wind at said zone in a second time period substantially shorter than said first time period.