Evaluation of Ionizing Radiation Effects on Device Modules Used in Wireless-Based Monitoring Systems

To increase the reliability of wireless-based monitoring systems under ionizing radiation environments, multiple diversified commercial off-the-shelf (COTS) modules have been used to achieve radiation tolerance. This paper presents experimental results of radiation tests on key modules in wireless-based monitoring systems, which include analog signal processing circuits, analog-to-digital converter (ADC) modules, microcontroller modules, and wireless transmission modules. In total, 12 modules have been evaluated, (i.e. 3 analog modules, 3 ADCs, 3 microcontrollers, and 3 wireless transmission modules). The radiation tests are conducted using the gamma radiator at The Ohio State University Nuclear Reactor Lab (OSU-NRL). The performance parameters of these 12 modules are investigated under high dose rate (20 krad(Si)/h). Experimental results have shown that the tested modules perform satisfactorily with little sign of degradation until the total dose levels reach the tolerable limits for these modules. Experimental results support the fact that, by using diversified COTS components, one may be able to achieve equivalent performance as those built by using radiation-hardened components, but with a considerable cost-saving. Furthermore, the tests also show that digital modules, particularly, with higher speed processors (i.e. microcontrollers) may be more susceptible to radiation than other types of modules. Therefore, additional shielding should be used to protect them.