基于Si-PIN探测器的X射线荧光光谱分析系统中数字脉冲处理器的综合性能研究

A Comprehensive Performance Study of Digital Pulse Processors in Si-PIN Detector-Based XRF Systems

  • 摘要: 数字脉冲处理器(Digital Pulse Processor,DPP)作为X射线荧光光谱(XRF)分析系统的核心,其性能直接决定了能谱质量与分析精度。传统的模拟多道分析器(Analog Multichannel Analyzer,MCA)受限于电路结构,存在严重的脉冲堆积与死时间效应,导致能量分辨率下降。随着数字化信号处理技术的发展,DPP为提高系统性能提供了新的途径,但相较于国外成熟产品,国产DPP的发展尚处于起步阶段。由此,本文介绍了国产数字脉冲处理器DPP_NCP1的设计方案与装备特性,同时与Si-PIN探测器耦合构建XRF实验系统,通过对比国产模拟多道分析器(NUMCA)及商用数字脉冲处理器(DP5X),系统评估了DPP_NCP1的整体性能。实验结果表明:DPP_NCP1采集的能谱主峰锐利、次峰清晰,无MCA系统的拖尾现象;在250 K和255 K工作温度下,其对Mn (5.9 keV)和Ag (22.1 keV)的能量分辨率较NUMCA均有显著提高,Mn提升约50%,Ag提升约60 eV;尽管DPP_NCP1的能量分辨率较DP5X略大3 ~ 10 eV,但其多次测量的能量分辨率相对标准偏差(RSD < 0.46%)明显低于DP5X;在峰位稳定性方面,DPP_NCP1在恒定温度下多次测量峰位漂移小于1道,且在250 ~ 255 K温变条件下,Mn与Ag主峰分别漂移约2 ~ 3道和9道,温漂特性与DP5X高度一致。DPP_NCP1与Si-PIN探测器的匹配方案在能量分辨率、信号稳定性及信噪比等关键指标上表现优异且具备可靠的工程应用价值。

     

    Abstract: The digital pulse processor (DPP) serves as the core of X-ray fluorescence spectroscopy (XRF) systems, where its performance dictates the quality of energy spectra and overall analytical precision. Traditional analog multichannel analyzers (MCA) are constrained by hardware architecture, leading to significant pulse pile-up and dead-time effects that degrade energy resolution. While digital signal processing offers a robust alternative, domestically developed DPP in China are currently in the early stages compared to established international products, necessitating rigorous validation of their performance and engineering utility. In this work, the design architecture and characteristics of the domestic DPP_NCP1 are presented, and its performance is evaluated within an XRF experimental system coupled with a Si-PIN detector. Comparative benchmarks are conducted against a domestic analog multichannel analyzer (NUMCA) and a commercial digital pulse processor (DP5X). Experimental results indicate that the energy spectra acquired by the DPP_NCP1 exhibit sharp primary peaks and distinct secondary peaks, effectively eliminating the tailing phenomena inherent in MCA systems. At operating temperatures of 250 K and 255 K, the energy resolution of the DPP_NCP1 for Mn (5.9 keV) and Ag (22.1 keV) shows significant improvements over the NUMCA, specifically enhancing the Mn resolution by approximately 50% and that of Ag by 60 eV. Although the energy resolution of the DPP_NCP1 is marginally higher than that of the DP5X (by 3–10 eV), its relative standard deviation (RSD < 0.46%) is notably lower, demonstrating superior measurement consistency. Furthermore, the DPP_NCP1 maintains high peak stability with a shift of less than one channel under constant temperature; under thermal fluctuations (250–255 K), the drift characteristics for Mn and Ag are highly consistent with those of the DP5X. These findings confirm that the DPP_NCP1, in conjunction with Si-PIN detectors, delivers excellent performance in energy resolution, signal stability, and signal-to-noise ratio, underscoring its significant potential for reliable engineering applications. The BRIEF REPORT is available for this paper at http://www.ykcs.ac.cn/en/article/doi/10.15898/j.ykcs.202506060150.

     

/

返回文章
返回