Differential AC anemometer

Details Differential AC anemometer Differential AC anemometer

1992-02-18

1993-11-23

Razavi, Michael T.

Measuring and testing

Volume or rate of flow

Thermal type

7386195, 7320425, G01F 168, G01P 510

Patent

active

052633802

ABSTRACT:
An apparatus comprises a sensor including a heater, an upstream detector and a downstream detector. An AC signal source excites the heater to generate propagating heat signals that are received by the upstream and downstream detectors. A first detecting circuit provides a first output signal responsive to the propagating heat signals received by the first detector and a second detecting circuit provides a second output signal responsive to the propagating heat signals received by the downstream detector. A difference circuit subtracts the first and second signals to obtain a difference signal and an output circuit provides an output signal responsive to the difference signal, which reflects both magnitude and phase. The resulting output signal has improved resolution and provides for improved sensor sensitivity.

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