Effects of Flexible Plastic Substrate Parameters and Conductive Ink Characteristics on The Performance of a Printed Frequency Selective Surface

In this paper the effects of flexible plastic substrate parameters and conductive ink on Polyethylene Terephthalate (PET) film are investigated on the performance of a cross shaped aperture frequency selective surface (FSS) designed at 24 GHz. The FSS unit cell is a cross shaped slot with equal arms designed on a square patch to be printed on a single layer plastic film with conductive ink. The crossed slot aperture was designed to resonate at 24 GHz with bandpass characteristic when illuminated with either x or y polarized incident plane wave at normal incidence due to the symmetry of the structure. The FSS unit cell was numerically investigated to determine the sensitivity of thickness, relative permittivity of the plastic film substrate and conductivity of printing ink on the performance characteristics of the FSS such as its reflectance, transmittance, and bandwidth. The FSS has overall dimensions of 7 mm x 7 mm x 0.134 mm (0.56λ x 0.56λ x 0.01λ at 24 GHz) with a bandwidth covering 22.38 - 25.86 GHz.