A SINGLE LASER ALL-FIBRE BASED OPTICAL SENSOR AND SWITCHING SYSTEM AND METHOD FOR MEASURING VELOCITY IN ATMOSPHERIC AIR FLOW

• Main Authors: MIKKELSEN, Torben, Krogh, MANN, Jacob, KRISTENSEN, Leif, DELLWIK, Ebba
• Format: Patent
• Language: English; French; German
• Published: 26.07.2017
• Subjects: ANALOGOUS ARRANGEMENTS USING OTHER WAVES; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION ORRERADIATION OF RADIO WAVES; MEASURING; MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION,OR SHOCK; PHYSICS; RADIO DIRECTION-FINDING; RADIO NAVIGATION; TESTING

A system for measuring a velocity of tracer particle motion in a fluid comprising at least one laser emitter configured to emit a continuous wave laser beam and a plurality of optical devices being configured to alternately receive a laser beam, focusing the laser beam onto a same probe volume comprising tracer particles, and receiving back- scattered light from the tracer particles. The optical devices have a common optical input/output port for transmitting the received continuous-wave laser beam and for receiving the backscattered radiation. The optical devices are provided to have mutual pointing angles so that each of the plurality of optical devices points at the probe volume under a different angle. A processor is configured to receive a part of the transmitted laser beam and the received backscattered radiation beam to calculate a Doppler shift, and thereby determine a plurality of velocity components of the tracer particles using coherent detection.