Collisional, Nonuniform Plasma Sphere Scattering Calculation by FDTD Employing a Drude Model

In a collisional plasma, the collision frequency between electrons and neutrals may be equal to or greater than incident electromagnetic wave frequency. The complex permittivity can not represent the dielectric property of the plasma perfectly used in the finite difference in time domain (FDTD). Drude model is adopted to characterize a collisional plasma. Using a commercial FDTD package, XFDTD 6.0, the electromagnetic scattering of plasma sphere is calculated. By comparison with Mie method, Drude mode is proven to be suitable. Radar cross-section (RCS) of nonuniform plasma spheres and conductor spheres coated by plasma layer are calculated.