Aiming at ranging and positioning requirement of moving objects in metal confined space

a split-type ultrasonic transmitting and receiving circuit is proposed

the component and working principle of which is analyzed. The principle of ultrasonic transmitting circuit is designed by combining high-power FET and mediumhigh frequency transformer

and the impedance matching between transmitting circuit and transducer is discussed.The ultrasonic receiving circuit is designed based on the functions of amplification

filtering and comparison. On the basis of the designed principle

the circuit hardware is realized

and the function of the realization circuit is actually tested. The peak-to-peak value of the driving waveform voltage generated by the ultrasonic transmitting module at the frequency of 40 k Hz reaches 300 V under the condition of a battery power of 700 mAh and a working voltage of 3. 7 V. The ultrasonic receiving module captures the ultrasonic voltage signal of peak-to-peak value up to12 V in a water-filled pipeline at a distance of 20 m. The test results are consistent with the expected design goals.The correctness and practicability of the circuit are verified.