Miniaturized Wideband Metasurface Antenna With Filtering Performance for 5G Application

A miniaturized wideband filtering metasurface antenna (MSA) is proposed, comprising 3×3 square metasurface elements and a driven patch. Symmetrically arranged shorting vias and an open stub induce the first two radiation nulls
${f_{\mathrm{{n1}}}}$
and
$f_{\mathrm{{n2}}}$
in the lower and upper stop-bands, respectively. To move the newly resonant point caused by
$f_{\mathrm{{n2}}}$
forward and expand the impedance bandwidth (IBW) of the filtering MSA, two slots are etched on the driven patch. Meanwhile, introducing the second radiation null
$f_{\mathrm{{n3}}}$
in the upper stop-band. After that, two L -shaped branches will help to enhance the roll-off rate by shifting
$f_{\mathrm{{n3}}}$
from 5.65GHz to 5.5GHz. Measurement of the prototype reveals a large 10-dB fractional IBW of 35.8% (from 3.55GHz to 5.1GHz) with an average realized gain of 7.1 dBi. What's more, the radiation aperture size is merely 0.41×0.41
${\lambda _{0}^{2}}$
, while maintaining the radiation suppression level of 16dB and 25.6dB at the lower and upper band edges, respectively, rendering this filtering MSA more promising for 5G (sub 6G) application.