The Digital Multi-channel Pulse Amplitude Analyzer Based On FPGA

The nuclear spectrum measurement system is a measuring instrument for ray energy.The multi-channel pulse amplitude analyzer is a key component of the nuclear spectrum measurement system which affects the performance of the nuclear spectrum measurement system directly.According to the characteristics of gamma ray spectrometry measurement's specfic requirements,The multi-channel pulse amplitude analyzer was designed.The multi-channel pulse amplitude adapt the technical scheme of “the nuclear front-end electronics circuits+digital signal processing part".On this basis,the key technologies of the following aspects are studied in detail:(1).The nuclear front-end electronics circuits are composed of preamplifier and amplifier spectrometer.First of all,the design scheme is put forward based on the theory of the nuclear front-end electronics circuit.Secondly,according to the experience,the design scheme was further improved.Finally,the feasibility and effectiveness of the design is verified by the method of software simulation and experiment(2).Digital signal processing part adopts a technical scheme of ”ADC+FPGA+USB”.According to the specific needs of the system,we choose the right chip to design each part of the hardware circuit design.In accordance with the overall design of the system,we will be combined in various parts and build the hardware platform of digital signal processing based on FPGA.(3).The software part is to complete the FPGA program design and the design of USB firmware.This paper adopts the top-down and modular design idea to complete the program design of the logic function module,such as the peak extraction,the spectrum and so onBased on the above research work,we complete the software and hardware design of multi-channel pulse amplitude analyzer and the software gradually.The test results show that the gamma ray nuclear spectrum measurement system which using this multi-channel pulse amplitude analyzer has a higher system stability and better energy resolution.It canmeet the needs of the nuclear spectrum measurement system.