Response of an open-ended slotted body of revolution to an ultra-wideband electromagnetic pulse

The general problem considered here is the computation of the complete electromagnetic response of a conducting open-ended body of revolution (BOR) which contains an electrically thin circumferential slot of variable conductivity. The distance along the generating arc is defined by the variable t. The unit vectors t and /spl phi/ represent the directions of the longitudinal and circumferential surface currents on the BOR. The incident electromagnetic wave is assumed to be an ultra-wideband plane wave pulse which is transverse magnetic (TM) to the BOR axis (z-axis). Of particular interest is the axial component of the electric field on the BOR axis in the vicinity of the aperture and the slot. The integral equation formulation and method of moments solution used here to determine the surface currents excited on a slotted BOR excited by a plane wave is in essence that of Mautz and Harrington (1969). The Mautz and Harrington formulation considers perfectly-conducting closed bodies only. For a problem involving a BOR which is open on one or both ends, the basis functions in Mautz and Harrington are modified as in Donohoe and Taylor (1995) in order to define the correct current behavior at the aperture edge. The BOR thickness is assumed to be infinitesimal. The formulation of Mautz and Harrington must be further modified in order to account for the finite conductivity of the slot.