PROBLEM TO BE SOLVED: To highly accurately obtain blood velocity over a wide range in comparison with a conventional one in an ultrasonic diagnostic device which transmits an ultrasonic beam into an analyte, obtains a reception signal by receiving an ultrasonic wave returned by reflection, calculates the blood velocity on the basis of the reception signal and displays blood flow velocity distribution in color.SOLUTION: An ultrasonic diagnostic device transmits ultrasonic beams with plural center frequencies in accordance with plural kinds of burst wave signals with mutually different transmission frequencies of pulses, generates plural kinds of reception signals in accordance with the plural kinds of burst wave signals, performs primary calculation of blood flow velocity for each kind of reception signal on the basis of a complex autocorrelation method for each kind of reception signal among the plural kinds of reception signals, and performs secondary calculation of blood flow velocity on the basis of plural calculated values of the calculated blood flow velocity.COPYRIGHT: (C)2015,JPO&INPIT【課題】本発明は被検体内に超音波ビームを送信し反射に戻ってきた超音波を受信して受信信号を得、その受信信号に基づいて血液速度を算出して血流速度分布をカラー表示する超音波診断装置に関し、従来と比べ広範囲に渡る血液速度を高精度に求める。【解決手段】パルスの送信周波数が互いに異なる複数種類のバースト波信号に応じた複数の中心周波数の超音波ビームを送波させて、複数種類のバースト波信号に応じた複数種類の受信信号を生成し、それら複数種類の受信信号のうちの各1種類の受信信号ごとに、複素自己相関法に基づいて各1種類の受信信号ごとの血流速度の1次算出を行ない、算出された血流速度の複数の算出値に基づいて血流速度の2次算出を行なう。【選択図】 図5