Procedure and circuit to characterise tissue by means of broad band ultrasonic pulse reflection, transfer of the echofrequency spectrum into the range of andible frequencies and diagnostics by hearing

摘要

The device consists of circuits (1-2-3) for transmitting high frequency ultrasonic carrier pulses to the tissue, circuits (1-4) for receiving the echoes and converting them into high frequency electrical signals, and circuits (5-6-10-11-14) for memorizing the said electrical signals with a sampling frequency that is high enough for the high frequency information they contain to be correctly recorded. Circuits (11 to 19) read the memorized information at a rate lower than the sampling frequency so that the high frequency spectrum is transposed to the audible frequency range. Circuits (7-8-9) then convert the transposed spectrum into an audible signal. …IMAGE…