Design and Prototyping of Transmissive RIS-Aided Wireless Communication

TL;DR

This paper presents the design, fabrication, and testing of a transmissive RIS with 1-bit phase control, demonstrating significant signal enhancement and potential for practical wireless communication improvements.

Contribution

It introduces a novel transmissive RIS design with 1-bit phase tuning, validated through prototype measurements and experimental communication system testing.

Findings

Achieved 1-bit phase control with minimal insertion loss.

Demonstrated over 20% bandwidth at 5.8 GHz.

Increased received signal power by approximately 7 dB with RIS deployment.

Abstract

Reconfigurable Intelligent Surfaces (RISs) exhibit promising enhancements in coverage and data rates for wireless communication systems, particularly in the context of 5G and beyond. This paper introduces a novel approach by focusing on the design and prototyping of a transmissive RIS, contrasting with existing research predominantly centered on reflective RIS. The achievement of 1-bit transmissive RIS through the antisymmetry configuration of the two PIN diodes, nearly uniform transmission magnitudes but inversed phase states in a wide band can be obtained. A transmissive RIS prototype consisting of 16 $\times$ 16 elements is meticulously designed, fabricated, and subjected to measurement to validate the proposed design. The results demonstrate that the proposed RIS unit cell achieves effective 1-bit phase tuning with minimal insertion loss and a transmission bandwidth of 3 dB exceeding $20\%$ at 5.8GHz. By dynamically modulating the quantized code distributions on the RIS, it becomes possible to construct scanning beams. The experimental outcomes of the RIS-assisted communication system validate that, in comparison to scenarios without RIS, the signal receiving power experiences an increase of approximately 7dB when RIS is deployed to overcome obstacles. This underscores the potential applicability of mobile RIS in practical communication.