Comprehensive Analysis of Highly Efficient, High-Gain, Modular and Scalable, Dual-Linear-Polarized Metalens Antenna for SatCom Applications
Metalens antennas are emerging as promising candidates for compact high-gain antenna systems in next-generation wireless and satellite communication applications, where stringent link-budget requirements demand highly directive yet lightweight and compact apertures. In such systems, improving aperture efficiency is critical because it reduces the physical aperture size required to achieve a target gain, thereby enabling antenna miniaturization. Although recent studies have explored generative artificial intelligence (AI) techniques for unit-cell optimization, realizing compact and efficient metalens antennas requires a broader metalens-system-level design approach. In this work, a modular, scalable, dual-linearly polarized metalens antenna is proposed through a systematic investigation of the key parameters governing aperture efficiency, thereby enhancing overall antenna compactness. Unlike prior works primarily focused on unit-cell optimization, the proposed approach jointly optimizes both the feed antenna and the metalens structure to achieve efficient aperture illumination and reduced effective aperture requirements. In particular, the study investigates: 1) unit-cell topology; 2) amplitude thresholding; 3) number of metal layers; 4) interlayer pattern variation; 5) unit-cell dimensions; and 6) spatial placement of unit cells based on feed characteristics. This holistic optimization significantly improves aperture efficiency, enabling high-gain performance with a comparatively smaller aperture. To support practical deployment, a modular architecture based on standard printed circuit board (PCB) panels is introduced, enabling scalable and low-cost fabrication with precise alignment achieved using 3-D-printed fixtures. The proposed design is experimentally validated using a $0.7\times 0.7$ m X-band prototype, achieving a maximum measured gain of 36.3 dBi and a high aperture efficiency of 60.2%. These results demonstrate the potential of the proposed approach for compact, high-gain, and cost-effective satellite communication ground-station systems.