Abstract
—Semantic communication, near-field operation, and integrated sensing and communication (ISAC) are often considered separately in terrestrial and non-terrestrial networks (TN– NTN). We show how a large electromagnetic aperture can connect them. Nonlocal metasurfaces and holographic apertures act on the spatial spectrum of an incident field and can execute linear projections, which form an early stage of semantic feature extraction , directly in the wave domain before digitisation, thereby reducing the corresponding digital processing burden. Near-field focusing also provides position-dependent sensing features, allowing the aperture to serve as an analog semantic-ISAC front end on resource-constrained aerial and satellite platforms. We describe the underlying physics, the co-design of constrained analog projections with lightweight digital decoders, and a case study in which a data-adaptive projection outperforms a fully digital baseline in the simulated energy-limited regime while transmitting four times fewer coefficients and using 11.4 times fewer decoder MACs. Finally, we identify relevant 3GPP, ITU-R, and ETSI activities and the remaining standardisation gaps.