Transmission properties study of PDGS with defected triangles

Periodic defected ground structures (PDGS) are the structures that are etched periodically on their ground plane, which can be used to prohibit the propagation of electromagnetic waves within a certain band of microwave frequency. PDGS with defected triangles can be used to prohibit the propagation of electromagnetic waves within a certain band of microwave frequencies. The precise transmission parameters of PDGS with defected triangles are obtained through FDTD analysis in this paper. PDGS with defected triangles have excellent stopband characteristic when periodic unit amounts and structure sizes meet appropriate specification. The deepness and width of stopband will increase with the increase of periodic unit amounts and etched triangle sizes, and the decrease of apex angle will also lead to the increase of the deepness and width of stopband. The precise relation given in the paper will provide powerful tool for the analysis and design of PDGS with defected triangles as microwave filter. Moreover, according to circuit theory the defected areas can be realized by not only triangle, but also other geometries such as rectangle, circle, hexagon, octagon, spiral, and so on.