Abstract:The increase of signal-to-noise ratio ( SNR) is an effective measure to improve the measurement accuracy of an ultrasonic flowmeter. However, the increase of transmission voltage for higher SNR could damage the ultrasonic sensor and the receiving circuit; it also introduces higher mutual interference between the transmitting and receiving circuits. Proposing an ultrasonic transceiver design for flow measurement of composite pipes: In the transmission circuit, a central-axis transformer instead of a damping resistor is used. In the receiving circuits, a limiting bridge circuit is employed for protection. The experimental results showed that the optimized transmission circuit proposed in this paper could increase the transmission voltage and reduce the discharge time. The output voltage is amplified by 13. 85 and 4. 5 times without and with loads, respectively. At the same time, the receiving circuit can effectively suppress the mutual interference and improves the power of the receiving branch. The transmission efficiency of the receiving circuits for signals below 5 V exceeds 90%. The circuit design was applied to a non-contact ultrasonic flowmeter, and the fluid in the composite pipeline was measured. The test results showed that the linearity and repeatability of the flowmeter had met the actual requirements of the flow measurement.