Reflection of a wave from a thin plasma layer attached to a metal plate by finite-difference time-domain analysis

The reflection of an electromagnetic wave in a thin plasma layer attached to a metal plate at high pressure is investigated with the finite-difference time-domain method. The effects of the plasma thickness, the plasma density distribution function, the collision frequency between electrons and neutrals and the frequency of incident wave on the reflection coefficient of the electromagnetic wave are discussed. Numerical results indicate that the reflection coefficient of the wave depends on its frequency, the plasma thickness, the plasma density distribution and the collision frequency. The reflection coefficient is low only at the low band of the calculated frequency for different plasma distribution functions if the plasma layer is very thin, e.g. 10 mm. Plasmas with an excess of 20 mm for a high collision frequency such as 103 GHz are capable of absorbing microwave radiation over a wider frequency range for different plasma distributions.