Method and device for measuring the distance of an object from an ultrasonic transmission/reception unit

US5671190A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Nils Kroemer · Hohenstein-Ernstthal, DE
• Martin Vossiek · Ergolding, DE

Key dates

• Filing date: Dec 18, 1995
• Grant date: Sep 23, 1997
• Expiry date: Dec 18, 2015

Classification

• Technology area (CPC G): Physics
• CPC primary: G01S15/101
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The method makes it possible, in particular, to measure distances which lie within the ambiguity zone of the ultrasonic transmission/reception unit. The ultrasonic transmission/reception unit comprises a single ultrasonic transducer which is operated in pulse-echo mode. The time t.sub.e1 of the first received echo is initially determined. If this time lies outside the double dead time 2t.sub.T, then the measurement is unambiguous and the propagation time of the sound, which is proportional to the difference between the ultrasonic transmission/reception unit and the object, is output. Otherwise, the propagation time of the sound is determined from the difference between the arrival times of two successive multiple echoes from the same object.