Study Of Suspended Solids Concentration Underwater Measurement System Based On FPGA

Water is the source of life,which is crucial to the development of human beings.However,with the rapid development of social productivity and the acceleration of urbanization,water environment pollution has become increasingly serious,which has attracted national attentions.Suspended solids concentration(hereafter called SSC)is one of the important factors of water environmental quality and an important indicator of environmental monitoring.It has become an important task in environmental monitoring about how to obtain information on water quality factors such as SSC efficiently and accurately.The traditional methods to estimate or measure the concentration of suspended matter have the problems such as high requirement,high cost or not real-time monitoring.To solve this problem,this paper proposes a underwater acoustic detection system based on FPGA to measures SSC.The system can sends and receives any type of signal,and use the ultrasonic power spectrum estimation to monitor the relative distribution of SSC and estimate the relative size of the suspended matter.The specific content includes:1.The basic knowledge of underwater acoustic communication platform mainly based on the design process and implementation principle of FGPA is introduced.The basic theory of power spectrum estimation is described,including the analysis and explanation of classical power spectrum estimation algorithm and AR parameter model of modern power spectrum estimation.2.With hardware devices and modules of FPGA,digital to analog converter,power amplifier,underwater acoustic transducer,combined with development tool Quartus II,this paper designs a underwater acoustic detection system,which allows sending and receiving any signals.The measurement signals of different frequency bands are used to carry out the data transmission and reception experiments,which realizes the function of data receiving and collecting after the measurement signals transmitting in different water environment.The feasibility of the system is verified and the experimental data is achieved and stored with experiments.3.The method of using the power spectrum estimation to obtain the relative distribution of SSC and the relative size of the suspended matter is proposed.With the experimental data,the characteristics of the suspended system is obtained according to the power spectrum estimation of the collected signal.And a user-friendly interface based on MATLAB is constructed to estimate and to display the output of the results.The results show that the SSC detection system underwater based on FPGA can measure the relative distribution of the SSCand the relative size of the suspended matter.