Study Of Acoustic Signal Processing And Data Transmission In Water Channel Flow Measurement

The topic of this paper is the study of acoustic signal processing and data transmission inwater flow measurement. Given the current domestic Level Meter measurement andautomation requirements,this paper studies acoustic signal processing in the levelmeasurement, and data transmission system.The paper’s content includes the following sections:1. The inaccuracy factors and corresponding improvement measures in water flowmeasurementFirstly,Author analyse the ultrasonic sounding principle to draw main error causes thatincluding the following aspects, the decline of the ultrasonic signals, the SNR of theultrasonic signal, the propagation speed of ultrasonic signal in the air, and test blind,Second,the corresponding improved approach was put formed.Adopt40KHz frequency sensorto weaken the fading of the ultrasonic signal in the air, design the best horn resonator toimprove the SNR and directional of the ultrasonic signal, compensate the acoustic velocity bybenchmarking method that Validity was verified, use DSP to control the energy of theemission of a signal pulse to reduce the blind spot of the ranging.2. The study of sound signal processing algorithm in embedded softwareThis part includes the relationship between sampling rate and ranging accuracy, anddelay estimation problem. we introduce the parabolic interpolation to increase the samplingrate. We analyze the existing digital filtering method, and introduce the median averagefiltering algorithm to improve the signal-to-noise ratio, Furthermore use matched filteringprinciple to detect the echo signal to identify peaks, at last estimate the test distance.3. The design of the data transmission systemThis section includes lower machine output interface design, RTU design andrealization,the programming of the Modbus communication protocol, and CDMA networktransmission model selection. 4. Verify the reliability of the data transmission system and the correctness of productprototypeThis section includes benchmark position calibration of benchmark method, as well as inthe laboratory and the field, the prototype accuracy verification and data transmission systemreliability verification.