Patent ID: 7614310
Filing Date: 2009-11-10
Classification: G01F,G01N,G01P

Abstract:
1. A method for determining the transit time (t) of an ultrasonic signal ( 15 ) from an ultrasonic sensor ( 6 ) that was launched into a measurement path (L) by an ultrasonic converter (A, B); the phase shift (Δφ) of the ultrasonic signal ( 15 ) is determined relative to a reference timing signal ( 8 ), and a remainder (r(t)) is determined as a measure of the transit time (t) of the ultrasonic signal ( 15 ), wherein the phase shift (Δφ) is determined using a quadrature demodulation scheme, with which the received ultrasonic signal ( the remainder (r(t)) is determined based on a characteristic quantity (t