Perfectly Conducting Structures With Low Signature in a Broad Band of Frequencies

ABSTRACT

This paper is about perfectly electrically conducting structures designed to produce negligible scattered power when exposed to a time‐harmonic plane electromagnetic wave. The structures feature cavities capable of concealing objects. Apart from examples of two‐ and three‐dimensional close‐to‐invisible structures, two findings concerning invisibility are presented. The first establishes a reciprocity relation for the far‐field scattering amplitude, and the second reveals the existence of nonradiating sources that generate substantial electromagnetic fields near the source region. The results have applications in low‐observable technology.