基于三角函数的核信号类高斯成形算法研究  

Trigonometric functions-based gaussian-like shaping algorithms for nuclear signals

作　　者：钱云琛 周建斌[1] 刘权卫 马英杰[1] 刘易 洪旭[1] QIAN Yunchen;ZHOU Jianbin;LIU Quanwei;MA Yingjie;LIU Yi;HONG Xu(College of Nuclear Technology and Automation Engineering,Chengdu University of Technology,Chengdu 610059,China;China Nuclear Power Engineering Co.,Ltd.,Beijing 100840,China)

机构地区：[1]成都理工大学核技术与自动化工程学院,成都610059 [2]中国核电工程有限公司,北京100840

出　　处：《核技术》2024年第6期56-64,共9页Nuclear Techniques

基　　金：国家自然科学基金(No.12075038);四川省自然科学基金(No.2024NSFSC0423)资助。

摘　　要：高斯信号具有高信噪比、抗弹道亏损和易于提取幅度等优点。因此,在核辐射测量系统中,核信号的高斯成形被广泛应用于探测器输出信号的滤波和幅度提取。然而,目前实时高斯成形核脉冲信号仍然具有挑战性。常见的Sallen-Key滤波器和CR-(RC)^(m)滤波器输出的类高斯信号还存在对称性差和下冲等问题。本文提出了一种基于三角函数的双指数信号类高斯脉冲成形算法。该算法以三角函数为基础,通过平移和反转可得到左右对称的类高斯信号(1-cosx),采用Z变换方法推导了该算法的数字递推式。仿真和实测结果表明:在相同达峰时间条件下,相较于正弦函数(sin)脉冲成形,类高斯脉冲成形具有更好的滤波性能,信噪比(SNR)提升了8.95%。同时,类高斯脉冲成形所得能谱的能量分辨率较sin脉冲成形更优。与梯形脉冲成形相比,类高斯脉冲成形具有更好的堆积脉冲分离能力,展现出良好的应用前景。[Background]Gaussian shaping is commonly used to filter and extract the amplitude of nuclear pulse signals owing to its high signal-to-noise ratio,resistance to ballistic loss,and ease of amplitude extraction.However,the problems of asymmetry and downwash exist in Gaussian-like signals generated by Sallen-Key and CR-(RC)^(m)filters.[Purpose]This study aims to address the problems of asymmetry and downwash in Gaussian-like signals generated by Sallen-Key and CR-(RC)^(m) filters,this paper presents a trigonometric function-based Gaussian-like pulse shaping algorithm for dual-exponential signals.[Methods]First,the impact of shaping parameters on the shaping pulse and filtering performance of the algorithm was examined by applying Gaussian-like pulse shaping to simulated nuclear pulse signals.Then,the filtering performances of Gaussian-like and sin pulse shaping algorithms were compared and analyzed using the same shaping width.Finally,the characteristic X-ray signals of manganese(FAST-SDD detector)were collected using a self-made digital nuclear signal acquisition board under various tube flows.The energy resolution and count rate characteristics of the energy spectra obtained from Gaussian-like,sin,and trapezoidal shaping algorithms were comparatively analyzed for different tube flows and shaping times.[Results]Comparison results show that Gaussian pulse shaping exhibits superior denoising performance to sin pulse shaping,with an 8.95%improvement in the SNR for the same peak arrival time.Additionally,the energy resolution of the spectrum obtained using Gaussian pulse shaping exceeds that of sin pulse shaping,and its stacking pulse separation ability outperforms that of trapezoidal pulse shaping,making it highly applicable.[Conclusions]Gaussian-like pulse shaping presented in this study demonstrats better stacking pulse separation capability than trapezoidal pulse shaping,indicating promising application prospects.

关 键 词：数字核脉冲信号 类高斯成形 三角函数数字成形 能量分辨率 

分 类 号：TL822.6[核科学技术—核技术及应用]