电子科技 ›› 2022, Vol. 35 ›› Issue (3): 1-7.doi: 10.16180/j.cnki.issn1007-7820.2022.03.001

• •    下一篇

基于反馈调节的闪烁脉冲稀疏量化电平方法

邓贞宙1,胡钦1,赖文升1,韩春雷1,2,陶凌1   

  1. 1. 南昌大学 信息工程学院,江西 南昌 330000
    2. 芬兰国家PET中心 图尔库大学中心医院,芬兰 图尔库 999018
  • 收稿日期:2020-11-04 出版日期:2022-03-15 发布日期:2022-04-02
  • 作者简介:邓贞宙(1987-),男,博士,教授。研究方向:辐射探测与成像系统。|胡钦(1996-),男,硕士研究生。研究方向:集成电路设计。
  • 基金资助:
    科技部03专项(20193ABC03A040);国家自然科学基金(61501197);江西省创新创业高层次人才“千人计划”创新人才长期项目(S2018LQCQ0554);澳门青年学者项目(AM201921);广东省微纳光子功能材料与器件重点实验室项目(91180198)

Sparse Quantization Level Method for Scintillation Pulse Based on Feedback Regulation

Zhenzhou DENG1,Qin HU1,Wensheng LAI1,Chunlei HAN1,2,Ling TAO1   

  1. 1. Information Engineering School,Nanchang University,Nanchang 330000,China
    2. Turku PET Centre,Turku University Hospital and University of Turku,Turku 999018, Finland
  • Received:2020-11-04 Online:2022-03-15 Published:2022-04-02
  • Supported by:
    Special Project of the Ministry of Science and Technology of China(20193ABC03A040);National Natural Science Foundation of China(61501197);Jiangxi Provincial Innovation and Entrepreneurship High-Level Talents "Thousand Talents Program" Innovative Talents Long-Term Project(S2018LQCQ0554);Macao Youth Scholars Program(AM201921);The Laboratory of Nanophotonic Function Materials and Devices of Guangdong(91180198)

摘要:

PET探测器采用SQL采样电路对闪烁脉冲进行处理,可固定量化电平。零点噪声引起的电平翻转导致电压比较器长时间非正常发热,无法设置较低的量化电平,限制了探测器符合时间分辨率的提高。文中提出一种基于反馈调节的闪烁脉冲处理方法,该方法通过使用三极管饱和状态下的开关特性,对SQL量化样本进行反馈调节。利用延迟元件对量化样本进行延迟同步,产生可以随样本逻辑电平变化的量化电平,避免了零点噪声对SQL采样电路的影响。实验结果表明,在相等时间内,优化的SQL采样电路的采样量比原SQL采样电路的采样量减少了29%,符合时间分辨率提升了179.3 ps,有效减少了PET探测器无用功耗,提高了PET系统的符合时间分辨率。

关键词: 正电子发射断层成像, 闪烁脉冲, 稀疏量化电平, 信号处理, 采样电路设计, 反馈调节, 符合时间分辨率, 性能优化

Abstract:

The PET detector uses SQL sampling circuit to process scintillation pulse and fix the quantization level. The electric flipping caused by zero noise leads to abnormal heat of the voltage comparator for a long time, and the lower quantization level cannot be set, which limits the improvement of the detector's coincidence timing resolution. This study proposes a flicker pulse processing method based on feedback adjustment, which uses the switching characteristics of the transistor in the saturation state to perform feedback adjustment on the SQL quantitative samples. The delay element is used to delay and synchronize the quantized samples to generate a quantized level that can vary with the logic level of the sample, avoiding the influence of zero-point noise on the SQL sampling circuit. The experimental results show that compared with the original SQL sampling circuit, the optimized SQL sampling circuit reduces the amount of samples by 29% in the same time, and coincidence timing resolution is improved by 179.3ps, which reduces the useless power of PET detector and improves the coincidence timing resolution of PET system.

Key words: PET, scintillation pulse, SQL, signal processing, sampling circuit design, feedback adjustment, coincidence timing resolution, performance optimization

中图分类号: 

  • TP391