Ultrasonic anemometer.

摘要

Ultrasonic probes which transmit (E1-E4) and receive (R1-R4) are arranged in such a way as to define at least three different paths for the propagation of ultrasound in air. A device (20) is provided to measure the time for the ultrasound to be propagated along the different paths and to calculate the wind speed and direction from the measured propagation times. The transmitting and receiving probes are low frequency probes. Each transmitting probe is intended to transmit an ultrasonic signal in the form of a predetermined wave train at an ultrasonic frequency between 10 and 200 kHz. The measuring and calculating system incorporates means for measuring the propagation time by correlation between a signal transmitted by a transmitting probe and a signal received by at least one receiving probe.
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