Reconfigurable Holographic Surface: A New Paradigm for Ultra-Massive MIMO

TL;DR

This paper introduces reconfigurable holographic surfaces as a lightweight, cost-effective alternative to phased arrays for ultra-massive MIMO, enabling advanced 6G communication and sensing with experimental validation.

Contribution

It presents the concept, working principles, and practical implementation of RHS, demonstrating its potential for cost-efficient, high-performance wireless communication and sensing.

Findings

Successful prototype implementation of RHS for wireless communication.

Experimental results show high performance and cost efficiency.

Outlines future challenges and research directions.

Abstract

Evolving from massive multiple-input multiple-output (MIMO) in current 5G communications, ultra-massive MIMO emerges as a seminal technology for fulfilling more stringent requirements of future 6G communications. However, widely-utilized phased arrays relying on active components make the implementation of ultra-massive MIMO in practice increasingly prohibitive from both cost and power consumption perspectives. In contrast, the development of reconfigurable holographic surface (RHS) provides a new paradigm to solve the above issue without the need of costly hardware components. By leveraging the holographic principle, the RHS serves as an ultra-thin and lightweight surface antenna integrated with the transceiver, which is a promising alternative to phased arrays for realizing ultra-massive MIMO. In this paper, we provide a comprehensive overview of the RHS, especially the RHS-aided communication and sensing. We first describe the basic concepts of RHS, and introduce its working principle and unique practical constraints. Moreover, we show how to utilize the RHS to achieve cost-efficient and high-performance wireless communication and sensing, and introduce the key technologies. In particular, we present the implementation of RHS with a wireless communication prototype, and report the experimental measurement results based on it. Finally, we outline some open challenges and potential future directions in this area.