Background radiation detector is a portable/fixed device used for real-time measurement of ionizing radiation levels such as natural or artificial gamma rays, X-rays, and cosmic rays in the environment. By using high-sensitivity detectors and energy spectrum analysis algorithms, it is possible to quickly identify environmental background values, abnormal artificial nuclides, or radiation leaks. Application scenarios: Customs/airport/subway: rapid clearance and radiation screening of luggage, packages, and mail; Surrounding nuclear facilities: environmental background monitoring and abnormal alarm; Medical and scientific research: on-site verification of radiation diagnosis and treatment facilities, laboratory waste; Public science popularization: Schools and communities conduct radiation safety demonstrations.