A bi-patch loaded microstrip line based 1-D periodic structure with enhanced stop bandwidth and band switching characteristics

Irfan Shahid*, Dushmantha Thalakotuna, Michael Heimlich

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

5 Citations (Scopus)


A one-dimensional periodic structure comprising of eight unit cells each having two metallic patches sandwiched between microstrip line and ground plane has been investigated. Patches bearing dissimilar dimensions present distinct reactive loads, determined by their respective areas, to generate relatively wider bandgap. Patches can be selectively connected to ground or left floating through a combination of vias and externally controlled FET switches. Dispersion analysis of the structure has been carried out to determine the propagating modes of the line for all four possible states of the unit cell. A top-down, design guide approach has been adopted with the effect of parameters determining performance attributes captured. The proposed structure acts as an all pass filter from DC to 19.5 GHz with all patches floating and exhibits stopband characteristics from 6 to 19.5 GHz with different combinations of the switches offering an overall stop bandwidth greater than 100%. The proposed structure offers tunability from no bandgap to bandgap with added advantages of band switching capability with double the number of unique reconfigurable switch patterns as compared to conventional single patch structures.

Original languageEnglish
Pages (from-to)1329-1342
Number of pages14
JournalJournal of Electromagnetic Waves and Applications
Issue number10
Publication statusPublished - 3 Jul 2019


  • Electromagnetic band gap (EBG)
  • periodic structures
  • reconfigurable filters
  • bandstop filters
  • dispersion analysis

Cite this