# A multifunctional smart field-programmable radio frequency surface

## TL;DR

A new radio frequency surface is developed that can dynamically adjust antenna performance across multiple communication standards with high efficiency.

## Contribution

The novel FPRFS design enables real-time reconfigurable antennas with radiation efficiency independent of switch count.

## Key findings

- FPRFS antennas achieve comparable efficiency to traditional antennas.
- Asymmetric excitation improves radiation efficiency regardless of switch number.
- Dynamic manipulation of return current enables adaptable antenna performance.

## Abstract

Antennas that can operate across multiple communication standards have remained a challenge. To address these limitations, we propose a Field-Programmable Radio Frequency Surface (FPRFS), which is based on manipulating current flow on its surface to achieve desirable RF characteristics. In this work, we demonstrate that substantial enhancements in radiation efficiency can be achieved while preserving the high reconfigurability of antenna structures implemented on the FPRFS. This is accomplished by utilizing an asymmetric excitation, directing the excitation to the low-loss contiguous surface, and dynamically manipulating the imaged return current on a segmented ground plane by switches. This important insight allows for adaptable antenna performance that weakly depends on the number of RF switches or their loss. We experimentally validate that FPRFS antennas can achieve efficiencies comparable to traditionally implemented antenna counterparts. This permits the FPRFS to be effectively utilized as a productive antenna and impedance-matching network with real-time reconfigurability.

A field-programmable radio frequency surface (FPRFS) is proposed that can implement arbitrary antennas and impedance matching networks. An asymmetric excitation scheme is demonstrated to ensure radiation efficiency independent of the number of FPRFS switches.