Patent ID: 8403853

Claim:
An ultrasonic diagnostic apparatus comprising: an ultrasonic transducer unit that transmits ultrasonic waves to receive an echo signal; a drive circuit that generates a pulse signal to drive the ultrasonic transducer unit; a preamplifier that amplifies the echo signal received by the ultrasonic transducer unit; a low frequency band attenuating filter that inputs the echo signal amplified by the preamplifier, attenuates the low frequency band component, and outputs a first resultant signal; a variable gain amplifier that inputs the first resultant signal outputted from the low frequency band attenuating filter, corrects an attenuated portion of the first resultant signal according to transmission time, and outputs a second resultant signal; an A/D converter that A/D converts the second resultant signal, as output by the variable gain amplifier, and outputs a third resultant signal; and a digital correction filter that intensifies the low frequency band component, which is attenuated by the low frequency band attenuating filter, of the digital signal which is converted by the A/D converter and outputted therefrom, and outputs a digital signal having a frequency distribution almost equal to that of the echo signal.