We will develop near-optimal cellular radio frequency (RF) architectures operating in the mid-band, aiming to enhance massive multiple-input multiple-output (MIMO) technology. We will derive the spatial degrees-of-freedom of the RF channel, which will give guidance on the number of needed baseband units and the optimal radiation patterns of the antenna array in the base station. In addition, we will develop signal-guiding metasurfaces to enhance the multipath richness of the propagation environment. The optimality of the volumetric antenna arrays and signal-guiding metasurfaces will be numerically evaluated and finally verified experimentally through fabrication of the RF designs and field measurements. The study will focus on the mid-band spectrum spanning between 6 and 20 GHz which is relevant and useful to the present and future needs of the cellular industry.

2025

2029