Programmable meta-fluid antenna for spatial multiplexing in fast fluctuating radio channels

Interference and scattering in fast-fluctuating radio waves, often considered undesirable, are inevitable in wireless communications, particularly in current mobile networks and the anticipated sixth generation (6G) systems, which are evolving into ultra-dense deployments. Current approaches relying on multiple-input multiple-output (MIMO) combined with artificial intelligence (AI)-aided signal processing suffer from drawbacks such as high power consumption and the need for wide bandwidth, raising scalability concerns. In this article, we present a radical approach that leverages the channel fading phenomenon to our advantage. Specifically, we propose what we believe to be a novel meta-fluid antenna architecture, referred to as the 'fluid' antenna system (FAS), which can exploit radio wave fluctuations with fine spatial resolution to opportunistically avoid interference, eliminating the need for complex signal processing. Our experimental results demonstrate that, under rich scattering conditions, the proposed meta-fluid architecture can harness the natural variations in radio waves to achieve spatial multiplexing. These breakthrough results demonstrate that scattering can be beneficial rather than harmful, and interference can be avoided rather than suppressed, fundamentally changing our perception of fading and our understanding of how interference should be managed in wireless communication networks.