Development Of Miniaturized Seismic Radon Anomaly Detection Electronics System Based On High-speed Digital Acquisition

Radon is one of the radioactive rare gases that can exist stably in nature for a period of time.Generally,radon element comes from the decay of uranium and thorium,so it is often enriched in the soil crust.Some studies have shown that the concentration change of radon in soil,underground water and atmosphere is closely related to the crustal activity.According to this,China has carried out the research on the relationship between earthquakes and radon anomalies in the 1990 s to achieve earthquake early warning by monitoring radon anomalies.However,due to the vast territory,complex landform and wide distribution of seismic zones in China,it is difficult to monitor and measure the radon concentration in various places.In the research of seismic radon anomaly,radon meters are usually used to measure and monitor the radon concentration in soil,underground water and atmosphere.When the existing radon meters are used to monitor the seismic radon anomaly,they usually need to use larger equipment and complex sampling operations to obtain effective data.Based on this,this project investigated various types of radon meters and their electronic systems on the market,and redesigned a miniaturization based on the new radon liquid scintillation sensor The electronic system of low-power radon meter equipment is applicable to widely distributed radon anomaly monitoring under various landforms.The electronics system in this paper uses high-speed digital acquisition and digital signal processing to process the signal of radon sensor.The hardware platform of the data acquisition electronics system is designed using ADS62P49 high-speed ADC and Xilinx Zynq So C.On the hardware platform,a software platform with the functions of receiving LVDS DDR digital bus,internal AXI clock domain data bus,gigabit Ethernet and serial interface dual-channel data upload is designed,The software and hardware platform can reliably complete the signal acquisition of radon sensor,have reliable internal data transmission function,and can reliably and stably communicate with other subsystems.According to the principle of radon sensor,the algorithm designs and implements a real-time radon detection algorithm based on waveform resolution and cascade case extraction.Radon data acquisition system uses waveform resolution algorithm α、βThe particle events are distinguished,and the unique information in the radon decay process is extracted through the cascade case extraction algorithm β-α Cascade decay events.The algorithm is implemented on the PL side and PS side of Zynq respectively according to the type of load required by the operation.The output result of the algorithm is the number of radon cascade decay events per unit time,and the upper computer can obtain radon concentration information through the result.In the process of design and implementation of radon data acquisition system,this paper has built an experimental environment to verify the software and hardware platforms and algorithms.Several software and hardware platform test programs are used to adjust the software interface parameters,and determine the reliability of the internal and external interfaces as well as the software and hardware platform.Then the radon source is used in the test environment to test the algorithm and hardware parameters that affect the performance of the algorithm,and the output results of the algorithm are analyzed to verify the reliability of the algorithm.The radon data acquisition system designed in this paper has the advantages of digitalization,miniaturization,low power consumption and intelligence.It can effectively process the signal of liquid scintillation radon sensor in the test of the data acquisition system and the preliminary cascade test of the radon detector,and shows the reliable radon event data acquisition performance,and realizes the effective radon anomaly detection function.The data acquisition system can meet the basic demand of mass production of radon meters.After further cost control,function integration and data calibration,the data acquisition system can meet the demand of commercial mass production,and has a good application prospect in the field of seismic radon monitoring.The data acquisition system can also be used as the data acquisition system of other radioactive sensors by replacing the algorithm module,which has certain application universality.