Research on the FDTD Method of Electromagnetic Wave Scattering Characteristics in Time-Varying and Spatially Nonuniform Plasma Sheath

3-D time-varying and spatially nonuniform plasma is applied using the finite-difference time-domain algorithm in investigating the effects of electromagnetic (EM) wave scattering in the plasma sheath. The plasma sheath is stratified in space, and three types of electron density in time-varying forms are assumed. The characteristics of different time-varying forms are analyzed using radar cross section (RCS). In addition, the effects of RCS change with time at Sand L-bands are investigated using electron density as the time variable. In the condition of timevarying and spatially nonuniform plasma sheath, the attenuation of EM wave is affected by different time-varying regularities of electron density (n
_e
). The RCS varying with time is related to the change rate of n
_e
.