COMMENT ON CHIRP EXCITATION OF ULTRASONIC PROBES AND ALGORITHM FOR FILTERING TRANSIT TIMES

Polkestad and Mylvaganam use a chirp technique to resolve an ambiguity in time-of-flight measurements. An alternative is to trigger an oscil loscope on one cycle of the initial tone burst, then vary the frequenc y. In the delayed burst, the correct cycle for time-of-flight measurem ents remains stationary.