Frequency Selective Surface Integrated Filtering Horn Antenna

We demonstrate a novel frequency selective surface (FSS) integrated with horn antenna which realizes filtering functionality. An elliptical transmission response with stop band isolation greater than 15 dB and transmission zeros closer to passband were achieved by a systematically designed FSS with shorting pins. This FSS array operates at X-band frequency range with center frequency 10 GHz and bandwidth ratio 8.8 % which was fabricated and integrated at the aperture of the pyramidal horn antenna. Due to its quasi elliptic behaviour, a high gain greater than <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{1 8} \mathbf{~ d B i}$</tex> and stopband isolation more than 15 dB were realized. FSS integrated filtering horn antenna is a good choice for microwave communications and sensing systems such as RADAR, satellite and radio astronomy.