Thin absorbing structure for all incidence angles based on the use of a high-impedance surface

It is shown that thin mushroom layers (high-inipedance sin-faces realized as regular arrays of small patches at a small distance from a face) can be used as radar-absorbing structures whose performance does not change with the incidence angle for TM-polarized waves. The key role of the vias connectors between the patches and the ground plane is explained, and potential performance demonstrated in examples. (C) 2003 Wiley Periodicals, Inc.