초록 ▼

An ultrasonic echo sounding apparatus disposed at a measuring location transmits ultrasonic pulses in successive transmission periods. The echo pulses received after reflection at a target are converted to electrical envelope signals which represent the envelope curves of the echo pulses. The envelo

An ultrasonic echo sounding apparatus disposed at a measuring location transmits ultrasonic pulses in successive transmission periods. The echo pulses received after reflection at a target are converted to electrical envelope signals which represent the envelope curves of the echo pulses. The envelope signals are transmitted via a connecting line to an evaluation apparatus disposed at an evaluation station remote from the measuring location. In the evaluation apparatus the envelope signals are evaluated for determining the target distance from the travel time of the ultrasonic pulses. The transmission of envelope signals results in the advantage that the information contained in the pulse shape of the echo pulses is available in the evaluation station, although it is not necessary to transmit signals having the high frequency of the ultrasonic pulses via the connecting line. Preferably, the envelope signals are transmitted in a first section of each transmission period, and low-frequency signals which are generated at the measuring location and are characteristic of parameters necessary for the evaluation of the envelope signals are transmitted in a second section of each transmission period. It is also possible to transmit control signals from the evaluation station to the measuring location during the second section of every transmission period.

대표청구항 ▼

A method of signal transmission between an ultrasonic echo sounding apparatus disposed at a measuring location and an evaluation station remote from the measuring location, ultrasonic transmission pulses being transmitted at the measuring location in successive transmission periods and the ultrasoni

A method of signal transmission between an ultrasonic echo sounding apparatus disposed at a measuring location and an evaluation station remote from the measuring location, ultrasonic transmission pulses being transmitted at the measuring location in successive transmission periods and the ultrasonic echo pulses received after reflection at a target being converted to electrical reception signals, comprising the steps of generating, at the measuring location, from said electrical reception signals electrical envelope signals which represent the envelope curves of the echo pulses and transmitting said envelope signals via a connecting line to the evaluation station in a first station section of each transmission period, the duration of said first section being at least equal to the maximum travel time of the ultrasonic transmission and echo pulses, said envelope signals being evaluated at the evaluation station for determining the target distance from the travel time of the ultrasonic pulses, generating at the measuring location at least one low-frequency electrical signal which is characteristic of a propagation medium parameter necessary for the evaluation of the envelope signals and transmitting said low-frequency electrical signal via the same connecting line to the evaluation station in a second section of the transmission period, and transmitting in the second section of the transmission period at least one control signal via the same connecting line from the evaluation station to the measuring location, which said control signal is distinguishable from the low-frequency electrical signal transmitted in the same second section of the transmission period via the same connecting line.