메타소자 기반 Reconfigurable Intelligent Surface 설계 및 분석 = Design and Performance Analysis of Reconfigurable Intelligent Surface with Meta-Devices

다국어 초록 (Multilingual Abstract)

A reconfigurable intelligent surface (RIS) that artificially reconstructs the wireless environment to achieve high spectral efficiency has been proposed in 5G and 6G broadband communication systems. However, there is no device technology capable of ideal 100% beam tuning, and most studies using integrated circuit (IC)-based metasurfaces have some limitations. This paper first formalizes the relationship in which the additional angular change of the reflected wave is determined by the phase tuning range of the RIS. Next, a methodology for designing RIS through meta-devices such as liquid crystals, 2D materials, and active THz materials is investigated. Thereafter, the performance of the RIS via system-level simulation is evaluated through 3D ray tracing that reflects the realistic communication scenario. Finally, we analyze the RIS system design and beamforming throughput performance that incorporates various meta-devices. As a result, this paper provides useful intuition for designing RIS suitable for the performance and application of the goal.

국문 초록 (Abstract)

무선 환경을 인위적으로 재구성하여 높은 스펙트럼 효율을 달성하는 재구성 가능 지능형 표면 (RIS)이 5G 및6G 광대역 통신 시스템에서 제안되고 있다. 하지만 이상적으로 100% 빔 튜닝이 가능한 소자 기술은 존재하지 않으며, 집적 회로 (IC) 기반 메타표면을 이용하는 대부분의 연구는 여러 한계를 가진다. 본 논문은 우선 RIS의 위상 튜닝 범위에 의해 반사파의 추가 각도 변화가 결정되는 관계를 공식화한다. 다음으로 액정, 2D 물질, 능동THz 물질과 같은 메타소자를 통해 RIS를 설계하는 방법론을 조사한다. 이후 실제적인 통신 시나리오를 반영하는3D 레이 트레이싱을 통해 시스템-레벨에서 RIS의 성능을 평가한다. 마지막으로 다양한 메타소자를 접목한 RIS 시스템 디자인과 빔포밍 스루풋 성능을 분석한다. 그 결과 본 논문은 지향하는 성능과 용도에 적합한 RIS 설계에유용한 직관을 제공한다.

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