Analysis of transient scattering from composite arbitrarily shaped complex structures.pdf

IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, VOL. 48, NO. 10, OCTOBER 2000 1625 Analysis of Transient Scattering From Composite Arbitrarily Shaped Complex Structures Tapan Kumar Sarkar, Fellow, IEEE, Wonwoo Lee, and Sadasiva M. Rao, Fellow, IEEE Abstract—A time-domain surface integral equation approach time to “travel” to the observation point. By properly choosing a based on the electric field formulation is utilized to calculate the time step, an explicit solution for the present-time currents may transient scattering from both conducting and dielectric bodies be obtained which may be solved recursively. So, once the cur- consisting of arbitrarily shaped complex structures. The solution rents at are determined, the time is incremented to the next method is based on the method of moments (MoM) and involves the modeling of an arbitrarily shaped structure in conjunction with the interval and the procedure is repeated. Since the present-time triangular patch basis functions. An implicit method is described currents are functions of previously occurring currents, the cur- to solve the coupled integral equations derived utilizing the equiva- rents need to be stored in a current history matrix. lence principle directly in the time domain. The usual late-time in- In this work, the transient scattering from arbitrarily shaped, stabilities associated with the time-domain integral equations are avoided by using an implicit scheme. Detailed mathematical steps composite three-dimensional (3-D), developed bodies is consid- are included along with representative numerical results. ered using the time-domain integral equation (TDIE). TDIE