【摘要】 以生活环境中的家用和类似器具电磁场分布为研究对象,根据电磁感应原理,采用环形线圈作为辐射检测探头,结合计算机技术设计了电磁辐射检测仪。介绍了环形线圈探头的设计,由高精度低噪声仪表放大器AD623组成的二级放大电路,以及模数转换和基于单片机AT89C51的软硬件设计。研究了采用螺线管作为参考源的辐射定标方法,通过测量螺线管内部磁场强度和放大电路输出电压之间的关系,在单片机程序中设置定标系数完成定标。在实际应用中能快速、准确地测量最大强度为20 mT的磁场,对生活环境中的电磁辐射污染起到了重要的评估作用。更多还原

【Abstract】 The paper takes the living environment in the household and similar appliances electromagnetic field distribution as the research object.According to the principle of electromagnetic induction,the annular coil is considered as the radiation detection probe,the electromagnetic radiation detector is designed with computer technology. Details of the design of a loop probe,two stages of amplifier circuit are composed of a high precision and low noise instrumentation amplifier AD623,and analog to digital conversion and the hardware and software are designed based on AT89C51 singlechip.The solenoid takes as a source of reference for radiometric calibration method,the relationship between the internal magnetic field strength of the solenoid and amplifying circuit output voltage is measured,a calibration coefficient is set by microcontroller program to complete the calibration.In practical application,the appliance can measure rapidly and accurately the magnetic field upto 2 mT,hence it can assess the effect of electromagnetic radiation pollution in the living environment.更多还原