Multi-channel Pulse Amplitude Analyser Based On FPGA

Nowadays,global warming,rising sea level,frequent geological disasters,especially nuclear leakage accidents,seriously threaten the survival of mankind.The acquisition and processing of nuclear information is of great significance in many basic and applied sciences.The energy spectrum of radioactive substances has certain regularity.The properties of radioactive substances can be understood by measuring the radiation of radioactive substances.Nuclear detectors are widely used in geosciences,nuclear energy utilization,aerospace,medicine,biology,chemistry and Environmental Sciences^[1].It has become a key scientific detection instrument in the field of nuclear energy.It plays a vital role in many fields,especially in the field of radioactive material detection.It is also of great significance to China's economic and social development.It is developing towards digitalization and intellectualization.The two-path multi-channel Nuclear radioactivity detection system designed in this paper takes the 14-bit AD9643BCPZ-170 chip as the module of analog-to-digital conversion?ADC?,the XC6SLX45 type of the Spartan-6 series of FPGAs produced by Xilinx Company as the pulse counting storage and control module,and Control and Network Interface Modules of STM32F4 Series High Performance Microcontrollers Based on Cortex?-M4 Produced by Italian Semiconductor Company.The system includes anterior attenuation circuit,peak detection and holding circuit,single-ended signal to differential signal circuit,ADC analog-to-digital conversion circuit,FPGA counting and storage circuit,control circuit,ARM network interface circuit,data transmission circuit and LabVIEW host computer.In the data transmission link,in order to transfer data efficiently,TCP?Transmission Control Protocol?is used.It applies many basic principles such as digital electronic technology and analog electronic technology,computer technology,signal and system.The main features of the system are:high parallel ability of FPGA as the core,dual detection,2048 channel counting,high speed,high integration,high accuracy,low power consumption,strong environmental adaptability,portability,flexible operation,etc.LabVIEW host computer enlarges,reduces,smoothes,counts ROI and searches for peaks to display the energy spectrum information accurately,clearly and conveniently.In the result of uranium 235 radioactivity test,the host computer clearly shows the counting value of each track.The functions of starting,stopping,gating,communication,sending indicator,enlarging,reducing,moving and ROI counting,spectrum smoothing,peak searching and data preservation of the energy spectrum of the region of interest are running normally.The results show that the system runs steadily and achieves the expected goals.