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ultrasonic motion detector

Ultrasonic motion detectors belong to the active motion detectors that emit an ultrasonic signal or an ultrasonic burst. The emitted ultrasound is reflected by objects, persons and liquids and is received and evaluated by the ultrasonic sensor

. If the ultrasound is emitted as a burst

, the temporal course of the reflection

changesdue to the Doppler effect

as soon as an object or person changes its position, i.e. moves. Ultrasonic

motion detector, photo:

motion detector, photo:

Ultrasonic motion detectors are used in security systems and alarm systems and are based on the reflection of ultrasonic waves. These can be reflected several times in corridors, even around corners. Therefore, ultrasonic motion detectors can also monitor corridors that go around corners. To avoid false alarms, ultrasonic motion detectors must not be placed behind curtains, near air conditioning vents or behind loosely hung objects.

Informationen zum Artikel
Englisch: ultrasonic motion detector
Updated at: 21.04.2016
#Words: 112
Translations: DE