The Sallen–Key filter(S–K)is widely used in nuclear pulse signal processing because of its simple working principle and good performance.Related research has only reviewed the recursive numerical model of digital S...The Sallen–Key filter(S–K)is widely used in nuclear pulse signal processing because of its simple working principle and good performance.Related research has only reviewed the recursive numerical model of digital S–K using idealized parameters.The use of digital S–K thus has limitations under these circumstances.This paper comprehensively deduces a recursive numerical model of digital S–K and discusses the effects of resistance and capacitance on the filter quality factor,cutoff frequency and amplitude–frequency response.The numerical recursive function,transfer function and amplitude–frequency response are analyzed using different parameters.From a comparative analysis of the shaper in a simulation and an actual nuclear signal,an optimal parameter selection principle is obtained.Using different forming parameters,the energy resolution and pulse counting rate of the 55Fe energy spectrum are compared and analyzed based on a Si-PIN detector.Capacitance has a stronger influence on the Gaussian shape,whereas the influence of resistance is stronger on the shaping amplitude.展开更多
Trapezoidal shaping method is widely applied to pulse amplitude extraction in digital nuclear spectrometer system,the optimal selection of the shaping parameters can improve the energy resolution and pulse counting ra...Trapezoidal shaping method is widely applied to pulse amplitude extraction in digital nuclear spectrometer system,the optimal selection of the shaping parameters can improve the energy resolution and pulse counting rate.From the view of noise characteristics,ballistic deficit compensation characteristics and pulse pile-up characteristics,in this paper the optimal selection of the trapezoidal shaping parameters is studied on.According to the theoretical analysis and experimental verification,the optimal choice of trapezoidal shaping parameters is similar to the triangle,the rise time is longer and the flat-top width is shorter.展开更多
CR–RCm filters are widely used in nuclear energy spectrum measurement systems. The choice of parameters of a CR–RCm digital filter directly affects its performance in terms of energy resolution and pulse count rate ...CR–RCm filters are widely used in nuclear energy spectrum measurement systems. The choice of parameters of a CR–RCm digital filter directly affects its performance in terms of energy resolution and pulse count rate in digital nuclear spectrometer systems. A numerical recursive model of a CR differential circuit and RC integration circuit is derived, which shows that the shaping result of CR–RCm is determined by the adjustment parameter (k, it determines the shaping time of the shaper) and the integral number (m). Furthermore, the amplitude– frequency response of CR–RC^m is analyzed, which shows that it is a bandpass filter;the larger the shaping parameters (k and m), the narrower is the frequency band. CR–RC^m digital Gaussian shaping is performed on the actual sampled nuclear pulse signal under different shaping parameters. The energy spectrum of 137Cs is measured based on the LaBr3(Ce) detector under different parameters. The results show that the larger the shaping parameters (m and k), the closer the shaping result is to Gaussian shape, the wider is the shaped pulse, the higher is the energy resolution, and the lower is the pulse count rate. For the same batch of pulse signals, the energy resolution is increased from 3.8 to 3.5%, and the full energy peak area is reduced from 7815 to 6503. Thus, the optimal shaping parameters are m -3 and k -0.95. These research results can provide a design reference for the development of digital nuclear spectrometer measurement systems.展开更多
基金supported by the National Natural Science Foundation of China(Nos.11665001 and 41864007)China Scholarship Council(No.201708360170)One Hundred People Sail in Jiangxi Province,Foundation of Key Laboratory for Radioactive Geology and Exploration Technology(No.RGET1309)
文摘The Sallen–Key filter(S–K)is widely used in nuclear pulse signal processing because of its simple working principle and good performance.Related research has only reviewed the recursive numerical model of digital S–K using idealized parameters.The use of digital S–K thus has limitations under these circumstances.This paper comprehensively deduces a recursive numerical model of digital S–K and discusses the effects of resistance and capacitance on the filter quality factor,cutoff frequency and amplitude–frequency response.The numerical recursive function,transfer function and amplitude–frequency response are analyzed using different parameters.From a comparative analysis of the shaper in a simulation and an actual nuclear signal,an optimal parameter selection principle is obtained.Using different forming parameters,the energy resolution and pulse counting rate of the 55Fe energy spectrum are compared and analyzed based on a Si-PIN detector.Capacitance has a stronger influence on the Gaussian shape,whereas the influence of resistance is stronger on the shaping amplitude.
基金Supported by National High Technology Research and Development Program of China(Nos.2012AA061804 and 2012AA061803)East China Institute of Technology Science Foundation(No.DHBK201111)Open-ended Foundation(No.HJSJYB2011-18)from the Chinese Engineering Research Center
文摘Trapezoidal shaping method is widely applied to pulse amplitude extraction in digital nuclear spectrometer system,the optimal selection of the shaping parameters can improve the energy resolution and pulse counting rate.From the view of noise characteristics,ballistic deficit compensation characteristics and pulse pile-up characteristics,in this paper the optimal selection of the trapezoidal shaping parameters is studied on.According to the theoretical analysis and experimental verification,the optimal choice of trapezoidal shaping parameters is similar to the triangle,the rise time is longer and the flat-top width is shorter.
基金supported by National Natural Science Foundation of China(Nos.11665001,41864007)National Key R&D Project(No.2017YFF0106503)+1 种基金China Scholarship Council(No.201708360170)One Hundred People Sail in Jiangxi Province,Open-ended Foundation from the Chinese Engineering Research Center(No.HJSJYB2014-03)
文摘CR–RCm filters are widely used in nuclear energy spectrum measurement systems. The choice of parameters of a CR–RCm digital filter directly affects its performance in terms of energy resolution and pulse count rate in digital nuclear spectrometer systems. A numerical recursive model of a CR differential circuit and RC integration circuit is derived, which shows that the shaping result of CR–RCm is determined by the adjustment parameter (k, it determines the shaping time of the shaper) and the integral number (m). Furthermore, the amplitude– frequency response of CR–RC^m is analyzed, which shows that it is a bandpass filter;the larger the shaping parameters (k and m), the narrower is the frequency band. CR–RC^m digital Gaussian shaping is performed on the actual sampled nuclear pulse signal under different shaping parameters. The energy spectrum of 137Cs is measured based on the LaBr3(Ce) detector under different parameters. The results show that the larger the shaping parameters (m and k), the closer the shaping result is to Gaussian shape, the wider is the shaped pulse, the higher is the energy resolution, and the lower is the pulse count rate. For the same batch of pulse signals, the energy resolution is increased from 3.8 to 3.5%, and the full energy peak area is reduced from 7815 to 6503. Thus, the optimal shaping parameters are m -3 and k -0.95. These research results can provide a design reference for the development of digital nuclear spectrometer measurement systems.
