Dual-band CPW Transparent Bandpass Filter for Wireless Communication

In this study, we present a new transparent flexible coplanar waveguide (CPW) bandpass filter using polyethylene terephthalate (PET) substrate while the simulation results permit to characterize the filter in terms of bandwidth, S-parameters, and current distribution. The resonator of the filter is implemented using a special compact square ring resonator patterned in the central conductor of a CPW transmission line. The impedance bandwidth of the proposed bandpass filter in the lower and higher frequency bands are 5.4% (10.3 to 10.87 GHz) and 11.2% (12.7 to 14.2 GHz) respectively, making this transparent filter suitable for dual-band X and Ku bands applications. Due to its foldable, bendable and transparent qualities, this filter can easily be integrated together with an OLED light source.

I. Introduction

Transparent passive microwave components are receiving more attention because of their useful application in transparent 3C products [1] . These components are mainly composed of transparent layers made up of conductive oxide sheets and flexible or nonflexible transparent substrates like polyethylene terephthalate (PET), glass, Plexiglas, etc .