| Popis: |
For the same frequency interference with ultrasonic which is difficult to eliminate with filter in the flow measurement of the engine thermal equilibrium, this paper puts forward the way which with pseudo-random code modulation sine wave as the drive signal for ultrasonic transducer. This paper analyzes the interference in the flow measurement of engine thermal equilibrium, and making use of the technology of eliminating the same frequency interference the author also studies the signal processing method of eliminating the same frequency interference based on pseudo-random code modulated sine wave shot by shoot transducer. According to the characteristics of sending and receiving signals, to eliminate the same frequency interference, this paper devises the flow measurement system of engine thermal equilibrium based on ultrasonic. Through experiment, this technology with pseudo-random code modulation sine wave as the drive signal for ultrasonic transducer can eliminate the same frequency interference which is difficult to eliminate in measurement, which not only improving the stability of the measurement system, but also the accuracy and precision of testing data. |
