在数字化能谱采集系统中,往往需要添加适当的脉冲成形算法对数字化核信号进行处理,以提升系统能量分辨率等指标。梯形成形算法因具有实现简单、成形脉冲窄等诸多优势而得到广泛的应用。从探测器输出的脉冲信号进行数学模型建立及简化出发,对信号模型的梯形成形算法进行分析讨论,并利用Simulink在现场可编程逻辑门阵列(Field-Programmable GateArray,FPGA)上实现并改进梯形成形算法,通过实验测试了成形算法的可行性及其在能谱测量过程中对能量分辨率的提升。
Background: Since the 1990s, with the rapid development of various digital devices, nuclear signal digital processing has been widely used. Purpose: To enhance energy resolution of digital spectrum system of nuclear radiation measurement, appropriate filter and pulse shaping algorithm is necessary. Trapezoidal filter is widely used for its advantage of easy to use and narrow pulse width, etc. Methods: The trapezoidal model and two kinds of trapezoidal filter algorithm based on simplified mathematical model of detector's output pulse signal are established. Results: The energy resolution of 137Cs spectrum has improved to 7.65% from 10.78%. Conclusion: Trapezoid shaping is necessary in nuclear signal digital processing.