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.
@article{arxiv.2508.11489,
title = {Liquid Crystal-Based RIS Loss-Trade-Off Analysis},
author = {Bowu Wang and Mohamadreza Delbari and Robin Neuder and Alejandro Jiménez-Sáez and Vahid Jamali},
journal= {arXiv preprint arXiv:2508.11489},
year = {2025}
}