ENDFIRE BEAMPATTERN PROCESSING FOR ACOUSTIC INTERFEROMETER

摘要

Arrangement for determination of an acoustic reflection coefficient of a sample by an acoustic interferometer, the interferometer including a tube, a sample holder, a transmitter, at least one receiver and signal processing means, the sample holder and the transmitter located inside the tube. In this arrangement the receiver is arranged to measure at a plurality of intermediate positions between transmitter and sample holder, an acoustic signal including a direct signal from the transmitter and a reflected signal from the sample; and the signal processing means are arranged: -to record the acoustic signal as a function of the intermediate position, -to separate the direct signal and the reflected signal from the measured signals at each intermediate position by endfire beampattem processing, and -to determine the acoustic reflection coefficient from an amplitude ratio of the separated reflected signal over the separated direct signal.