A new level measurement method based on acoustic standing wave

A new level measurement method based on acoustic standing wave is presented. Firstly, the system model about the frequencies of the acoustic standing waves is established and Kalman filter is used to preprocess the standing wave frequency. It will increase the accuracy of level measurement by reducing the influence of environment noise and measurement error, which are usually ignored by most of acoustic level measurement methods. Secondly, the new conversion technique can be given to calculate the level height with estimates of standing wave frequencies from Kalman filter. And it can overcome the strict limitation about frequency range in existing classical method. Moreover, the experiments show the proposed method effective.