Full-wave evaluation of a 40 dBi: Transmit-array for Ka-band SoTM

Abstract

Transmit-array (TA) antennas have been shown to be a cost-effective solution for the new generation of satellite communications. These antennas are usually composed by thousands of fine-tuned subwavelength unit-cells. Therefore, full-wave evaluations become quite challenging as the required gain increases, constraining the antenna design and optimization. This is aggravated by the fact that, when beam scanning is required, higher gains cannot be obtained by simply scaling a given design. In fact, for a F/D ratio, the maximum gain of the TA is limited by the scanning aberrations. Recently, we have proposed a new phase compensation law for the TA, designated as the bifocal correction, that allows to overcome the usual gain/scanning tradeoff limit. However, due to the lack of computational resources, we were only able to demonstrate this concept for a 40 dBi TA using PO/GO methods. In this communication we present the full-wave performance of this 40 dBi bifocal TA design using a new efficient numerical evaluation method, properly validated with a smaller 30 dBi TA.