Application Research Of Waveform Digitization In Physics Experiments

Waveform digitization technology has broad application prospects in the field of signal readout in modern physics experiments.It can retain almost all of the physical information of the signal.In recent years,with the development of electronics,the performance of waveform digitization is getting higher and higher,while the cost and power consumption are decreasing.Currently,the use of waveform digitization technology for signal readout in physics experiments has become a trend.The characteristics of various physics experiments are different,and the requirements for readout electronics vary widely.Therefore,for different physics experiments,it is necessary to design a corresponding waveform digitization scheme.Aiming at several typical physics experiment applications,this thesis presents the corresponding waveform digitization system frameworks.These applications are:1)signal readout of filter-fluorescer spectrometer in ICF experiment,2)measurement of complex radiation environment in space capsule,3)data acquisition in university nuclear physics experiment teaching.These designs make full use of the advantages of waveform digitization technology,solve the key problems of signal readout in each applications,and show the advantages of waveform digitization technology compared with traditional measurement methods.The main work and innovations of this thesis are as follows:(1)In ICF experiment,the strong radiation environment is very disadvantageous to the readout of the diagnostic signals.Due to the feature that the digital signal obtained from waveform digitization has strong anti-interference ability,this thesis presents a design of front-end waveform digitizer,which successfully realizes digitization of diagnostic signal of filter-fluorescence spectrometer with a sampling rate of 5GSPS and 10 bits resolution.Compared to the traditional method using long cables and oscilloscopes,the waveform digitizer at front end effectively overcomes the problems of signal loss,bandwidth limitation,and waveform distortion caused by long cables,and the accuracy and reliability of measurement have been significantly improved,it is very beneficial for the accurate diagnosis of hot electrons.(2)The information of the radiation field in the space cabin is of great significance for the assessment of astronauts' radiation risk and various scientific experiments in the space station.In this thesis,a design of readout electronics system for space radiation environment monitoring module in cabin based on waveform digitization technology is presented,which can realize the identification and spectrum measurement of neutrons and various charged particles.The use of waveform digitization for signal acquisition simplifies the circuit structure,reduces the number of components,and improves the reliability,so that longer-term monitoring of radiation environment in the cabin can be achieved.(3)In the university nuclear physics experiment teaching,the experiment content involves the measurement of a variety of ray and the use of a variety of detectors.Experiments require various measurements such as counting,spectrum,and waveform.Based on the versatility and flexibility of waveform digitization technology,this thesis develops a universal data acquisition system for nuclear information.Based on a 250 MSPS and 14 bits waveform digitizer,the system developed flexible DSP algorithms to realize the measurement of counting,spectrum,and waveform.Compared with discrete nuclear electronics instruments,this design simplifies the instrument structure,reduces the cost,and improves the maintainability of the system.