Supplies a drive pulse to the transducer for transmission to the subject a transmission signal of the ultrasonic waves, the ultrasonic diagnostic apparatus may be transmitted to the subject, respectively, and an inverted component forward component of the waveform of the ultrasonic and a signal processing section for removing the fundamental component by adding a transmitter, the received signal from the subject, the load connected to the transmitting unit, the transmitting unit, an amplitude that is output from the transmission circuit , according to at least one of the frequency or wavenumber, and comprises a switching unit for varying the output period in the half cycle of the transmission signal.本発明の超音波診断装置は、超音波の送信信号を被検体に送信するために振動子に駆動パルスを供給し、超音波の波形の正転成分と反転成分とをそれぞれ被検体に送信する送信部と、前記被検体からの受信信号を加算することにより基本波成分を除去する信号処理部とを備え、前記送信部は、該送信部に接続される負荷、該送信回路から出力する振幅、周波数、または波数の少なくとも一つに応じて、前記送信信号の半周期内における出力期間を可変とする切換部を具備する。
