| 摘要 |
PROBLEM TO BE SOLVED: To achieve miniaturization and cost reduction by simplifying the constitution of an echo phasing circuit. SOLUTION: An A/D converter 46, at each channel, samples input signals at 4n times the frequency at which ultrasonic waves are transmitted. For electronic control of ultrasonic beams, these outputs are delayed by a delayer 50 and made to match one another in phase, after which the input signals from each channel are added together by an adder 52. From an output of the adder 52 where 4n data align per cycle, data that deviate from one another by (n) are used as the actual and imaginary number components of complex signals. |
