Simulation of X-Rays Effect on Cavity Filters Based on SO-FDTD Method

Radiation interference on electronic devices is not negligible, and it is very important to analyze the causes of interference and the impact it has. This letter investigates the effect of X-rays on the output frequency of metal cavity filters. X-rays can generate primary and secondary electrons in the filter cavity. These electrons together form a plasma that affects the transmission characteristics of the electromagnetic wave, and thus interferes with the operation of the filter. To investigate this phenomenon, first a geometric modeling of 3-D metal cavity filter filled with plasma is constructed; then it is converted into a computable electromagnetic model of time domain finite difference (FDTD). Second, the electromagnetic wave transmission in the filter after exposure to X-ray radiation is calculated using the shift operator-FDTD method. Finally, after simulating the transmission characteristics, the results indicate that at different moments (1–3.5 ns) and at different air pressures (0.2 and 0.3 Torr), the frequency selection characteristics of the metal cavity filter change significantly, and the signal is even completely cut off in severe cases, which provides a reference for the performance of electronic devices within ionizing radiation environments.