A low profile filtering antenna based on metasurface

A Metasurface (MS) based filtering antenna with low profile, wide bandwidth and high gain is investigated in this paper. It is fed by a pair of microstrip-coupled slots from the bottom. The open stub of microstrip feed-line is elaborately designed to produce two radiation nulls right near band-edges for high frequency selectivity, while a separation is introduced into the slot to offer good suppression in lower stopband and parasitic strips are parallelly added to the microstrip feed-line to provide good suppression in upper stopband. Consequently, the filtering antenna with profile of 0.06λ has a 10-dB impedance bandwidth of 21.8%, an average gain of 10 dBi within passband, and an out-of-band suppression level of more than 29 dB within lower stopband of 2-4GHz and more than 21dB within upper stopband of 6-8GHz.