Quad Band Frequency Selective Surface with Band Rejection Characteristics

In this paper, a quad band Frequency Selective Surface (FSS) for rejection characteristics is proposed. The proposed design consists of two square rings patches placed on top and bottom structure of the substrate FR4. It rejects at 3.2, 5.8, 8.5 and 14.1 GHz frequencies operating in S, C, X and ku bands with rejection bandwidth ranging from 2.3- 3.7GHz, 5.4- 6GHz, 7.3- 9.3GHz and 12.3- 15.3GHz. The designed antenna has a good angular stability up to 60 degrees. It can be used for shielding purpose. The designed quad band filter has advantages like compact size with unit cell
$\mathbf{10}\mathbf{mm}\times \mathbf{10}\mathbf{mm}$
, and
$\mathbf{2} \times \mathbf{2}$
array of
$\mathbf{20}\mathbf{mm}\times \mathbf{20}\mathbf{mm}$
good angular stability compared to previous work as reported in literature.