基于贝叶斯反卷积的冲激成形方法  

Impulse Shaping Method Based on Bayesian Deconvolution

作　　者：贾通慧 刘易 王明[1] 马英杰[1] 王博 JIA Tonghui;LIU Yi;WANG Ming;MA Yingjie;WANG Bo(College of Nuclear Technology and Automation Engineering,Chengdu University of Technology,Chengdu 610059,China)

机构地区：[1]成都理工大学核技术与自动化学院,四川成都610059

出　　处：《原子能科学技术》2025年第4期926-933,共8页Atomic Energy Science and Technology

基　　金：国家自然科学基金(12075038)。

摘　　要：能量范围是评定能谱探测系统性能的指标之一。为获取更宽的能量范围,提出了一种反卷积脉冲冲激成形方法。该方法首先将测量到的脉冲信号写成冲激信号与系统的响应函数卷积的形式,通过贝叶斯公式推理冲激信号的公式,然后利用Z变换替换掉公式中有关卷积的部分,最终将测量到的脉冲信号展开为冲激信号。该方法较好地抑制了反卷积带来的噪声扩大,保留了更多低幅值脉冲,在一定程度上扩宽了能谱的能量范围。X光管的管压设置为20 kV,管流设置为73.6μA,使用该方法进行测量,结果表明,当冲激脉冲的判别阈值降到30 mV时,本文提出的方法能保留测量峰值的同时,对低能部分脉冲进行有效提取,从而完成对低能能谱的构建。A novel impulse shaping method based on Bayesian deconvolution as a means of enhancing the energy range of the energy spectrum was proposed.The initial step of this method entailed expressing the measured pulse signal as the convolution of the current impulse pulse signal and the detection system response function.Then,the measured signal was expressed in the continuous time domain and decomposed into the form of an impulse signal and a double exponential kernel convolution by derivation.Subsequently,Bayesian deconvolution should be performed on the measured signal,after which the expression of the impulse signal can be solved.It is important to note that due to the limitations of the double exponential kernel in terms of length,the Z-transform was employed as a substitute for the convolution process in Bayesian deconvolution.The simulation experiment was conducted to examine the nuclear pulse signal,utilizing the MATLAB software.The results demonstrate that the Bayesian deconvolution pulse shaping method is an effective approach for resolving the impulse signal embedded within a double exponential signal.And this method enables precise characterization of the amplitude,occurrence time,and number of pulses present in the original nuclear signal.A comparison with alternative impulse shaping methods,including inverse system cascade impulse shaping and Z-transform impulse shaping,demonstrates that the Bayesian deconvolution impulse shaping method is capable of effectively suppressing noise in a double exponential signal with a signal-to-noise ratio of 40 dB,thereby enabling the complete solution of the impulse signal.The experimental test was conducted using a CIT-3000MD X-ray fluorescence spectrometer measurement system,which was based on a FAST-SDD detector produced by Amptek Inc.This system was equipped with a thermoelectrically cooled solid-state detector and a preamplifier.The light source was a silver target X-ray tube,which was designed by Shanghai KeyWay Electronic Technology Co.,Ltd.The results show that,in

关 键 词：贝叶斯反卷积 冲激成形 核脉冲处理 

分 类 号：TL99[核科学技术—核技术及应用] TN782[电子电信—电路与系统]