Metasurface-Enabled ELAA: Electromagnetic Modeling and Beamspace Angle Acquisition

Abstract

Extremely large-scale antenna arrays (ELAAs) have emerged as a key technology for meeting the unprecedented performance demands of next-generation wireless systems. To improve their practical deployability, we propose metasurfaceenabled extremely large-scale antenna (MELA) systems, which replace conventional phase-shifter-based front ends with reconfigurable transmissive metasurfaces, allowing a small number of active feeds to wirelessly excite a large passive aperture. Physically grounded models are developed to characterize electromagnetic field propagation through individual transmissive unit cells, capturing the fundamental physics of wave transformation and transmission. Based on the resulting channel model, a beamspace scanning strategy is devised for angular acquisition in hybrid near- and far-field scenarios. Numerical results validate the fidelity of the electromagnetic modeling and the effectiveness of the proposed angle estimation, highlighting MELA as a promising architecture for practical ELAA deployments.