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硬件结构框图如下:Ⅰ为超声探头电路,采用陕西师大应用声学研究所研制的超声多普勒血流计,用来产生频移讯号.其中:1为发射电路,产生3MHz 的电汛号;2为组装在一块的发射、接收换能器。其中的发射换能器用来将1产生的电讯号转换为超声讯号,射向在液体中下落的小球;接收换能器则将由小球反射回来的超声讯号转换为相应的电讯号,送接收电路;3为接收电路.对接收换能器送来的电讯号放大、整形后送给差频电路;4为差频电路,
Hardware block diagram is as follows: Ⅰ for the ultrasonic probe circuit, the Institute of Applied Acoustics, Shaanxi Normal University developed Doppler ultrasound Doppler blood flow meter used to produce frequency-shift signal. Where: 1 for the launch of the circuit, generating 3MHz power flood number; 2 for the assembly of a launch, receiving transducer. Wherein the transmitting transducer is used to convert the electrical signal generated by 1 into an ultrasonic signal and to the small ball that drops in the liquid; the receiving transducer converts the ultrasonic signal reflected by the ball into the corresponding electrical signal and sends the received signal Circuit; 3 for the receiving circuit. The receiving transducer to send the electrical signal amplification, shaping sent to the difference frequency circuit; 4 for the difference frequency circuit,