Adaptive Three Layer Hybrid Reconfigurable Intelligent Surface for 6G Wireless Communication: Trade-offs and Performance

TL;DR

This paper proposes a three-layer hybrid reconfigurable intelligent surface (RIS) for 6G wireless communication that adaptively switches between active, passive, and inactive states to optimize performance and energy efficiency.

Contribution

It introduces a novel three-layer hybrid RIS architecture capable of dynamic reconfiguration based on link quality and power conditions, verified through fabrication and simulation.

Findings

Hybrid RIS outperforms standalone passive or active RIS in simulations.

The proposed structure adapts to link fluctuations, improving signal gain.

Energy-performance trade-offs are analyzed for different RIS configurations.

Abstract

A potential candidate technology for the development of future 6G networks has been recognized as Reconfigurable Intelligent Surface (RIS). However, due to the variation in radio link quality, traditional passive RISs only accomplish a minimal signal gain in situations with strong direct links between user equipment (UE) and base station (BS). In order to get over this fundamental restriction of smaller gain, the idea of active RISs might be a suitable solution. In contrast to current passive RIS, which simply reflects and directs signals without any additional amplification, active RISs have the ability to enhance reflected signals by the incorporation of amplifiers inside its elements. However, with additional amplifiers, apart from the relatively complex attributes of RIS-assisted arrangements, the additional energy consumption of such technologies is often disregarded. So, there might be a tradeoff between the additional energy consumption for the RIS technologies and the overall gain acquired by deploying this potential advancement. The objective of this work is to provide a primary idea of a three-layer hybrid RIS-assisted configuration that is responsive to both active and passive RIS, as well as an additional dormant or inactive state. The single RIS structure should be capable of adjusting its overall configuration in response to fluctuations in transmit power and radio link quality. Furthermore, our fabricated passive RIS-assisted structure verifies a portion of the proposed idea, with simulations highlighting its advantages over standalone passive or active RIS-assisted technologies.