Abstract
This chapter presents a design methodology for the synthesis of multiband and broadband electromagnetic bandgap devices based on the mushroom or Sievenpiper structure. The methodology described herein is based on the non-uniform capacitive loading of mushroom structures using lumped capacitors. The documented analysis begins with the observation that the bandgap of a mushroom-type metasurface shifts to lower frequencies once a load capacitance is applied across the gaps defined between the patches of neighboring unit cells. Our analysis further reveals that if, instead of the uniform capacitive loading, a non-uniform scheme is applied, then the resulting structure is characterized by a significantly wider stopband. In the first part of this chapter, the theoretical basis behind 122the non-uniform capacitive loading of electromagnetic bandgap (EBG) surfaces is investigated and additionally the theoretical analysis of the proposed methodology is presented. Afterward its applicability is demonstrated through representative examples that involve the investigation of the isolation properties of EBGs embedded into transverse electromagnetic (TEM) waveguides. From a practical standpoint the key aspect of the proposed methodology is the multiport network representation of the EBG. This allows the structure to be analyzed using simple circuit-type calculations rather than full-wave simulations. In the second part, this design methodology is extended to the case of open structures and again its applicability is demonstrated through indicative examples. Finally, in the third part, the aforementioned circuit-based EBG synthesis approach is adapted for the design of tunable absorbers that utilize the mushroom unit cell loaded with tuning capacitive and resistive lumped elements.
Original language | English (US) |
---|---|
Title of host publication | Broadband Metamaterials in Electromagnetics |
Subtitle of host publication | Technology and Applications |
Publisher | Pan Stanford Publishing Pte. Ltd. |
Pages | 121-164 |
Number of pages | 44 |
ISBN (Electronic) | 9789814745697 |
ISBN (Print) | 9789814745680 |
DOIs | |
State | Published - Jan 1 2017 |
All Science Journal Classification (ASJC) codes
- General Engineering
- General Materials Science