Patent ID: 6383140
Filing Date: 2002-05-07
Classification: G01S

Abstract:
An ultrasonic diagnosis device comprising:wave transmitting means for driving repeatedly a group of ultrasonic elements disposed in an array and generating ultrasonic waves; digital converting means for sampling reception signals obtained by detecting reflection echoes in said ultrasonic element group at a sampling frequency higher than a Nyquist frequency of an upper limit of a signal band of the reception signals, and converting them to digital signals; mixing means for multiplying each of said digital signals by reference signal; accumulating means for accumulating the digital signals multiplied, a number of said digital signals accumulated being equal to a number of a plurality of samples; wave reception focusing means for imparting a delay for aligning a phase difference peculiar to each of said ultrasonic elements to the digital signals accumulated, and adding the digital signals; and mixing data generating means for serially supplying data obtained by discretizing a signal having a frequency changing with a lapse of time from a wave transmission to said mixing means as said reference signal; said mixing data generating means including data computing means for computing in advance discrete values of said signal having the frequency changing with the lapse of time from the wave transmission, and memory means for storing said discrete values computed, and serially outputting said discrete values stored under control of read addresses.