基于数值微分核脉冲信号数字处理方法

核反应堆核测量系统测量探测器输出的核脉冲信号，该信号后沿拖尾很长，在计数率较高时容易产生信号堆积和基线漂移等问题，导致源区计数率测量上限仅能达到105 Hz左右。文中基于数值微分方法，采用数字处理技术，在时域上分析了核脉冲信号经过前置放大、信号成形、低通滤波和脉冲甄别后的输出，并利用探测器实测信号进行了仿真。仿真结果表明，基于数值微分的数字处理方法可以实现相邻0.4 μs脉冲信号的识别和测量，将源区测量计数率上限提升到2×106 Hz以上。 

Digital Processing Method Based on Numerical Differential of Nuclear Pulse Signal

Nuclear reactor instrumentation system measures the nuclear pulse signal output by the detector. The trailing edge of the signal is very long, and the problems such as signal accumulation and baseline drift are likely to occur when the counting rate is high. Thus, the upper limit of the source range counting rate can only reach 105 Hz. Based on numerical differentiation method, this paper analyzes the output of the signal after preamplification, the signal shaping, the low-pass filtering and pulse discrimination in the time domain by digital processing technology, and the simulation is carried out based on the signal measured by the detector. Simulation results show that, the digital processing method based on numerical differentiation can realize the identification and measurement of adjacent 0.4 μs pulse signals, and raise the upper limit of the source range counting rate to 2×106 Hz or more.