Doppler velocity detection device and ultrasonographic device using the same

A Doppler velocity detection device comprising:

• means for transmitting/receiving pulse waves to/from a subject a plurality of times;
• and
• velocity analyzing means for analyzing a velocity of a moving reflector in the subject on the basis of a reception echo signal,
• wherein the velocity analyzing means obtains a complex expansion coefficient by linearly connecting an expansion coefficient of an even-numbered degree term and an expansion coefficient of an odd-numbered degree term which is different from the even-numbered degree term by one degree, derived when reception echo time-series signals obtained by arranging reception echo signals of equal lapse time from pulse transmission times in order of the transmission times are expanded as components of a Legendre polynomial starting from the 0th degree, by using an imaginary unit as a coefficient, and obtains a signed velocity signal of a moving reflector in the subject on the basis of the ratio between the magnitude of each complex expansion coefficient and the magnitude of an interval between the complex expansion coefficients.

An ultrasonographic device comprising:

• an ultrasonic probe;
• means for allowing the ultrasonic probe to transmit/receive ultrasonic pulse waves to/from a subject a plurality of times;
• and
• velocity analyzing means for analyzing velocity of a moving reflector in the subject on the basis of reception echo signals from the subject,
• wherein the velocity analyzing means expands reception echo time-series signals obtained by arranging reception echo signals of equal lapse time from transmission times of the ultrasonic pulses in order of the transmission times as components of a Legendre polynomial, and obtains a velocity signal of a moving reflector in the subject on the basis of the magnitude of each of the expansion coefficients.

An ultrasonographic device comprising:

• an ultrasonic probe;
• means for allowing the ultrasonic probe to transmit/receive ultrasonic pulse waves to/from a subject a plurality of times;
• and
• velocity analyzing means for analyzing velocity of a blood flow in a moving organ in the subject on the basis of reception echo signals from the subject,
• wherein the velocity analyzing means obtains a complex expansion coefficient by linearly connecting an expansion coefficient of an even-numbered degree term and an expansion coefficient of an odd-numbered degree term which is different from the even-numbered degree term by one degree, derived when the reception echo time-series signals obtained by arranging reception echo signals of equal lapse time from transmission times of the ultrasonic pulses in order of the transmission times are expanded as components of a Legendre polynomial starting from the 0th degree, by using an imaginary unit as a coefficient, and obtains a signed velocity signal of the blood flow in the subject on the basis of the ratio between the magnitude of each complex expansion coefficient and the magnitude of an interval between the complex expansion coefficients.

An ultrasonographic device comprising:

• ultrasonic wave transmitting/receiving means for allowing a plurality of ultrasonic probes to transmit/receive an ultrasonic pulse to/from a subject a plurality of times;
• a transmission beam former for controlling a transmission focal position of an ultrasonic pulse in the subject;
• a reception beam former for controlling a reception focal position in the subject;
• a controller for controlling the ultrasonic wave transmitting/receiving means, the transmission beam former, and the reception beam former;
• and
• velocity analyzing means for analyzing velocity of a moving reflector in the subject on the basis of reception echo signals from the subject,
• wherein the velocity analyzing means obtains a complex expansion coefficient by linearly connecting an expansion coefficient of an even-numbered degree term and an expansion coefficient of an odd-numbered degree term which is different from the even-numbered degree term by one degree, derived when reception echo time-series signals obtained by arranging reception echo signals of equal lapse time from transmission times of the ultrasonic pulses in order of the transmission times are expanded as components of a Legendre polynomial starting from the 0th degree, by using an imaginary unit as a coefficient, and obtains a signed velocity signal of a moving reflector in the subject on the basis of the ratio between the magnitude of each complex expansion coefficient and the magnitude of an interval between the complex expansion coefficients.