Ray-based UTD representation of the field radiated by a magnetic current distribution over a PEC convex surface

Abstract

In this paper, a uniform geometrical theory of diffraction (UTD) ray solution is developed for describing in a collective fashion the radiation fields produced by a magnetic traveling wave (TW) surface current which is conformal to a doubly curved, smooth convex surface made of PEC. The fields are described collectively, in terms of just a few rays which are launched from specific critical points in the interior and on the boundary of the whole area occupied by the surface TW current. In practical applications the magnetic surface current can result from the application of equivalence theorem on the convex surface housing antenna arrays, which are conformal to a portion of a much larger and complex platform: an aircraft fuselage, a spacecraft body, a satellite, etc. The magnetic surface current is subsequently expanded into a finite set of magnetic TW surface currents, whose radiation is efficiently treated through UTD ray techniques. The proposed approach, once integrated in a UTD ray code, allows a drastic reduction of the time required for the prediction of the interaction of array antennas with their complex platform, when compared to a standard element-byelement description.