摘要 |
An ultrasonic pulse Doppler blood flow meter, wherein an amplitude equalizing circuit is inserted between the high-pass filter provided in the successive stage of the Doppler detector and the Doppler analyzer. The amplitude equalizing circuit not only effectively utilizes the input dynamic range of the Doppler analyzer but also automatically adjusts the cut-off frequency of the high-pass filter in accordance with the input signal. Therefore, a blood flow meter which requires minimal manual adjustment is obtained.
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