Demonstration of Optically and RF Transparent High-Efficiency Antenna by Quasi-1D Slow Wave Structure

In this paper, a new method of optically and RF transparent antenna based on quasi-one-dimension (quasi-1D) slow-wave structure is proposed. We demonstrate the high confinement, phase manipulation and mode suppression of quasi-1D slow-wave structure in antenna design. Without the dependence of transparent conducting materials, this method utilizes quasi-1D slow-wave structure, offering the feasibility for realizing highly optically and radiofrequency (RF) transparent antenna. To verify the proposed mechanism, an optically and RF transparent antenna with high radiation efficiency is design and fabricated, offering highly optical and RF transparency. The optical transmittance of proposed antenna reaches 93.7%, and the average RF transmittances of horizontal and vertical polarization are 81.2% and 84.3% in 5G n257 (26.5 ～ 29.5 GHz) and n258 (24.25-27.5 GHz) band, respectively. The antenna operates within 14.5-15.5 GHz, with the radiation efficiency of 72%-88% and the measured realized gain of 5.9-7.4 dBi. The simulated and experimental results verified the great potential of quasi-1D structure for electromagnetic manipulation and developing optical and RF transparency in antenna design.