Transparent Monopole Antenna with Ultra-wide Bandwidth Utilizing CPW Feeding

The purpose of this study is to design an ultra-wideband transparent monopole antenna based on CPW feeding, suitable for the 1 GHz~16 GHz communication frequency band. Indium tin oxide (ITO) thin film is deposited on a glass substrate using sputtering technology as the antenna radiating material to achieve high transparency. The antenna has dimensions of 60 mm×55 mm and consists of two layers of 1.8 mm-thick glass substrates, with the bottom glass serving as a reflector to enhance gain in the lower frequency bands. CST simulation results demonstrate that the antenna exhibits ultra-wideband performance covering 1 GHz~16 GHz with a maximum gain of -3.2 dBi across the entire frequency range, which is further validated by experimental measurements. The negative gain is attributed to the special high-loss properties of the ITO material, which still allows effective signal reception in certain application scenarios. Therefore, it is necessary to consider other performance metrics to evaluate the antenna′s suitability. Despite the challenge of lower gain in the 0~1 GHz range, this design still holds potential for applications in the 1 GHz~16 GHz communication frequency band.