A study of defect modes in one dimensional electromagnetic band gap structures

Electromagnetic band gap (EBG) structures have great potential in microwave communications. This paper reports a study of defect modes in one dimensional EBG structures. Effects of the size and permittivity of a defect in one dimensional EBG structure on the band gap property were investigated. Samples of EBG structures were fabricated by a cutting and inserting method. Transmission properties of these EBGs were simulated using a high frequency structure simulator and measured through a transmission/refection method. The defect mode was analyzed based on interference theory of electromagnetic waves and the resonance frequencies were calculated accordingly. The calculated results are in good accordance with the simulation and measurement. This research extends the study on the physical features of defects in EBG structures, providing a way to tune the working frequencies of EBG-type wireless communication devices.