Aiming at the problem that the echo signal is difficult to accurately locate in ultrasonic wave flow measurement

an echo localization method based on maximum peak detection is proposed.After the forward and reverse filtering of the echo sampling signal

the zero position of the normal waveform is located according to sampling data.The position of the echo signal is determined by determining the position of the waveform quality and the maximum peak value by comparing the neighborhood point with the peak value.The flow measurement experiment is carried out on the ultrasonic flowmeter system based on digital signal processor（ DSP） and field programmable gate array（ FPGA） dual core.The flowmeter is calibrated by the experimental data of the standard table.The flow measurement experiment with different flow rates has lower reference error and measurement repeatability.It is suitable for the measurement of gas flow in pipes.