JPS56124028A - Ultrasonic thermometer - Google Patents

Abstract

PURPOSE:To enable formation of a signal having high S/N ratio at receiving part without increasing output of transmission and reception by a constitution wherein a plurality of groups of pulse waves are transmitted with a phase based on a parttern set beforehand and made to have a prescribed phase in the receiving part for composition thereof. CONSTITUTION:Based on a pattern set beforehand by a code setting circuit 14, a phase inverting circuit 10 changes the phase of the output of an oscillating circuit 1 for every one group thereof and supplies the output thus changed in phase to a transducer 2. On the reception side, the received wave is converted into the phase of a final pulse by a phase inverting circuit 11. A delay circuit 12 delays the inputted signals till the time of reception of the final pulse wave respectively and each of the delayed pulse wave and the pulse wave of the final group are composed in a composing circuit 13, whereby one group of pulse waves are newly formed. The output pulse wave of the composing circuit 13 becomes a pulse wave which is strong against outside noises and S/N ratio thereof is improved compared with that of pulse waves forming only one group.