Application of DFT in bi-static RCS calculation of complex electrically large targets

摘要

To handle the electromagnetic problems of the bi-static radar cross section(RCS) calculation of scatterer in a wide frequency band, a finite-difference time-domain(FDTD) extrapolation method combining with discrete Fourier transform(DFT) is proposed. By comparing the formulas between the steady state field extrapolation method and the transient field extrapolation method,a novel extrapolation method combining with DFT used in FDTD is proposed when a transient field incident wave is introduced. With the proposed method, the full-angle RCS distribution in a wide frequency band can be achieved through one-time FDTD calculation.Afterwards, the back-scattering RCS distributions of a double olive body and a sphere-cone body are calculated. Numerical results verify the validity of the proposed method.