Enhancing the Bandwidth in Transmitarray Antennas Using Tapered Transmission Line Matching Approach

This paper proposes an innovative method to improve the bandwidth of transmitarray antennas using a tapered transmission line approach. A novel three-layer perforated dielectric unit-cell is introduced: it is made up by a central layer, with a varying size square hole, and two linearly tapered matching layers. To validate the proposed solution, a wideband transmitarray composed by 60x60 elements and working in Kaband has been designed and simulated. The simulated structure has a size of 15lambdax15lambda and it provides a 1-dB gain bandwidth of 27.4%, an aperture efficiency of 45.3% and a gain of 31.1 dB at 30 GHz.