Design And Implementation Of Multi-channel Ship Noise Signal Acquisition Module

The propeller vibration and the hydrodynamic force will generate noise signals when the ship is sailing,which has a huge impact on the lives of the crew,the normal operation of equipment,and the safety of navigation.The monitoring of ship noise is a key function of the work of ships.The research of ship noise signal acquisition technology is of great significance for vibration and noise reduction and the improvement of navigation safety.In view of the above situation,this thesis aims to design a ship noise signal acquisition module to monitor the noise signal generated by ship navigation,and provide the possibility for noise prediction and noise reduction design research.Firstly,this thesis analyzes the three types of noise signals in the ship.In order to accurately measure the three kinds of noise signals,the design indicators of the signal acquisition module are proposed.Considering the large number of signal channels to be measured and each channel must be compatible with three kinds of noise signals,the overall scheme of the multi-channel signal acquisition module based on the FPGA+ARM control platform is designed,and the factors affecting the acquisition accuracy are analyzed.The calculation methods of noise and errors in the hardware circuit are summarized.Then,the hardware circuit of the signal acquisition module is designed in detail.Among them,the analog part mainly realizes signal conditioning functions,including gain switching circuit,low-pass filter circuit and ADC drive circuit.The digital part includes analog-to-digital conversion circuit,control circuit and ethernet interface circuit,and the whole acquisition module is powered by a low-noise power supply circuit.According to the calculation method of multi-level circuit noise and error,the noise and error in the analog part of the acquisition circuit are estimated.In addition,in order to improve the measurement accuracy,a digital filtering algorithm and error calibration software are designed for data processing.Finally,the functions and indicators of the multi-channel signal acquisition module are tested and verified.Based on the test results of DC voltage accuracy and dynamic performance such as bandwidth and measurement range,the multi-channel ship noise signal acquisition module designed in this thesis can meet the design requirements.