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arXiv · 2508.11489

Liquid Crystal-Based RIS Loss-Trade-Off Analysis

Bowu Wang·Mohamadreza Delbari·Robin Neuder·Alejandro Jiménez-Sáez·Vahid Jamali
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Abstract

Liquid crystal (LC) technology has emerged as a promising solution for large reconfigurable intelligent surfaces (RISs) at millimeter wave (mmWave) bands, offering advantages such as low power consumption, scalability, and continuously tunable phase shifts. For LC-RIS based on the delay-line architecture, i.e., with dedicated phase shifters, there exists a trade-off between the maximum achievable phase-shift range and the corresponding insertion loss, which has not been studied for LC-RIS-assisted wireless systems yet. In this paper, we investigate this trade-off where a base station (BS) and an RIS are configured to minimize the transmit power while satisfying a given quality of service (QoS) for a number of users. Simulation results reveal a fundamental trade-off between the total transmit power and the achievable data rate as a function of the LC phase-shift range.

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Bowu Wang, Mohamadreza Delbari, Robin Neuder, Alejandro Jiménez-Sáez, Vahid Jamali. 2025-08-15. Liquid Crystal-Based RIS Loss-Trade-Off Analysis. https://doi.org/10.1109/wsa65299.2025.11202776

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