The function of signal pre-processi

The function of signal pre-processing includes signal transformation, active filtering, signal calibration and so on. Its performance directly affects the accuracy and validity of the measured signal. the specific circuit structure is shown in figure 3. since the vibration between the low-frequency vibrations defined in this paper is 0.15 and 10 Hz, the interference above 50 Hz can be filtered through high-order low-pass filters, but considering that low-frequency vibration sensors usually have low sensitivity and weak output signals, if some special measures are not taken, the absolute low-frequency vibration signals are easily submerged so that the circuit noise is submerged, and special attention has been paid to the design of the test method. although there are many factors that affect the performance of signal detection and processing circuits, the main factors affecting low frequency signals are temperature drift. the circuit noise and the temperature drift and random interference of various random interference active circuits have obvious time-varying characteristics, which leads to the lie of actual detection of output signals. Therefore, this paper presents a simple and effective method to detect the parameters of low frequency absolute vibration signals.