Inverted Microstrip Gap Waveguide Coplanar EBG Filter for Antenna Applications Articles uri icon

publication date

  • September 2022

start page

  • 1

end page

  • 17


  • 18, 2951


  • 11

Electronic International Standard Serial Number (EISSN)

  • 2079-9292


  • The possibility of making compact stopband filters using coplanar-coupled EBG resonators
    in inverted microstrip gap waveguide technology is studied in this work. To do this, the filtering
    characteristics of different configurations of mushroom-type elements are shown in which the shortcircuit element is placed on the edge of the resonator"s patch. The behavior of the structure as well as its main advantages such as: low losses, self-packaging, low level of complexity, flexibility and easy design are illustrated in the paper. To evaluate the possibility of integrating these structures in gap waveguide planar antennas feeding networks, a 5-cell EBG filter was designed and built at the X band. The proposed filter reached a maximum rejection level of -35.4 dB, had a stopband centered at 9 GHz and a relative fractional bandwidth below -20 dB of 10.6%. The new compact filter presented a flat passband in which it was well matched and had low insertion losses that, including the connectors, were close to 1.5 dB in most of the band. These results are enough to improve low-complexity future antenna designs with filter functionalities in this technology.


  • Telecommunications


  • gap waveguide technology; inverted microstrip gap; stopband filter; metamaterial; electromagnetic bandgap structure; artificial magnetic surface; antenna feeding network; antenna array; x band