Efficient near-field computation for radiation and scattering from conducting surfaces of arbitrary shape

A new algorithm for numerical evaluation of the fields in the near zone of conducting scatterers or antennas of arbitrary shape is developed in the present work. This algorithm is simple, fast, robust and is based on a preceding calculation of the current. owing on the conducting surface using the electric. led integral equation (EFIE) technique that employs the Rao-Wilton-Glisson (RWG) basis functions. To examine the validity of the near field computational algorithm developed in the present work, it is applied to calculate the near field due to plane wave incidence on a variety of conducting scatterers. The solution obtained for the fields in the near zone is found to satisfy the boundary conditions on both planar and curved scatterer surfaces and the edge condition for structures possessing edges or corners. The solutions obtained using the new algorithm are compared with those obtained using some commercial packages that employ the finite-difference-time-domain (FDTD). The algorithm defined in the present work gives results which are more accurate in describing the fields near the edges than the results obtained using the FDTD.