2023 年 20 巻 5 号 p. 20230022
An optical transparent antenna using indium tin oxide (ITO) for ultra-wideband (UWB) multiple-input multiple-output (MIMO) applications is proposed. The ultrathin ITO film is coated on a 67×67mm2 glass substrate and over 85% transparency is achieved. The antenna consists of four coplanar waveguide (CPW)-fed antenna elements with rotationally symmetric placement. The adjacent elements are placed orthogonally to produce dual polarisation and reduce coupling. The MIMO antenna operates from 1.5 to 11GHz which covers the UWB applications. The coupling between the elements is less than -23dB. Mean effective gain (MEG), envelope correlation coefficient (ECC) and diversity gain (DG) achieve excellent values which guarantee good MIMO performance. The prototype is verified and the measured results are analysed.
