Ultrasonic Transit Time Measurements Using Fast Analog to Digital Conversion and a Fast Fourier Transform Based Algorithm

摘要

This paper describes the application of a fast (100MHz) analog to digital voltage converter and a discrete fast Fourier transform based algorithm to the determination of ultrasonic transit times. The precision obtained was typically better than 1 nanosecond. Transit times over a range of frequencies (2-7MHz) have been measured using a broadband transducer excited by a chopped CW RF pulse. The frequencies chosen corresponded to those available from the discrete fast Fourier transform. Documented listings of the programs used are provided. (Author)