Off-line Digital Pulse Signal Processing Technology Of Space Radiation Detector

Spatial radiation environment is the main environmental factor causing spacecraft material and device performance degradation or even failure.Spatial radiation effects can cause deep charge and discharge effects,single-particle effects and other effects.Which poses a serious threat to the electronic devices and the control system as well as the entire spacecraft.At the same time,space radiation also threatens the life and health of the astronauts.Therefore,it is necessary to expand the study of space radiation detection to improve the reliability of spacecraft control system and ensure the normal operation of spacecraft.First of all,we studied the principle of signal acquisition and the whole acquisition process of the signal.Analyzed the influence of the probe and the electronic part on the signal finally collected,the results show that part of the scintillator probe will make the collected signal have interference signal;the electronics will have unavoidable noise impact on the finally collected signal,so it needs to remove t interference signal and reduce noise.Secondly,according to the characteristics of the output signal,smoothing,asymmetric Gaussian fitting and Fourier transform are performed.Smoothing can reduce a part of the noise in the pulse waveform and make the pulse waveform smooth.Applying the smoothing to the identification of n/? particles can improve the discrimination performance,and get the quality factor of n/ gamma identification ability up to 1.087.In order to get more accurate fitting signals,the smoothing processing is used as the preprocessing of fitting processing,and the smoothed pulse information is used to fit it,then the fitting curve is closer to the original pulse waveform,and the accuracy of the fitting results is improved.The combination of Fourier transform and low-pass filtering reduces high-frequency noise superimposed on the signal and smoothes the pulse shape.Furthermore,the relationship between TOT and pulse energy is studied under two different threshold setting methods: fixed threshold and relative threshold.When the fixed threshold is set to 5 mV,there is a linear relationship between TOT and pulse energy.However,with the threshold increase,the relationship between TOT and pulse energy will gradually deviate from this linear relationship,and the corresponding non-linear relationship can be obtained by over fitting.Under the relative threshold setting,by means of averaging,it can be concluded that there is also a linear relationship between TOT and pulse energy,so energy can be measured by TOT.Finally,the definition of the long and short gate of PSD pulse waveform is redefined to make the length of integral time change with the change of pulse waveform,which can better adapt to the pulse waveform.However,the pulse waveform filtering algorithm needs to be further improved to eliminate the waveform superimposed on the event.