Portable X/gamma-ray survey meter based on the Internet of Things network for measuring the environmental radiation distribution

In this study, we developed a portable X/gamma-ray survey meter for large-scale distributed real-time monitoring of the ambient dose equivalent rate in the surrounding environment, using a silicon photomultiplier coupled with a CsI(Tl) scintillator. This innovation is integrated into an Internet of Things (IoT) network. The device realizes a wide range of dose rate measurements by switching the frequency of a pulse-frequency modulation (PFM) -type DC-DC power supply mode. The energy response is improved through Geant4 simulation and multicomparator design. The energy response of the survey meter ranges from 48 keV to 1.3 MeV, encompassing common protection level applications. It effectively measures gamma radiation dose rates ranging between 0.1 uSv/h and 100 mSv/h for Co-60. Temperature compensation of the detector was achieved through a series of experiments; the meter exhibits a deviation of -25% to +25% at temperatures between -40 and +40℃.