Liquid crystals (LCs) technology have a well-established history of applications in visible light, particularly in the display industry. However, with the rapid growth in communication technology, LCs have become a topic of current interest for high-frequency microwave (MW) and millimeter-wave (mmWave) applications due to promising characteristics such as tunability, continuous tuning, low losses, and price compatibility. To improve the performance of future communication technology using LCs, it is not sufficient only with the perspective of radio-frequency (RF) technology. Therefore, it is imperative to understand not only the novel structural designs and optimization of MW engineering but also the perspective of materials engineering when implementing advanced RF devices with maximum performance for next-generation satellite and terrestrial communication. Herein, based on advanced nematic LCs, polymer-modified LCs, dual-frequency LCs, and photo-reactive LCs, this article summarizes and examines the modulation principles and key research directions for the design strategies of LCs for advanced smart RF devices with improved driving performance and novel functionality. Furthermore, the challenges in development of state-of-the-art smart RF devices that use LCs are discussed.

中文翻译：

---

用于微波和毫米波应用的先进智能设备的液晶：下一代通信的最新进展

液晶 (LC) 技术在可见光领域有着悠久的应用历史，特别是在显示器行业。然而，随着通信技术的快速发展，LC 因其可调谐性、连续调谐、低损耗和价格等有前景的特性而成为高频微波 (MW) 和毫米波 (mmWave) 应用当前关注的话题。兼容性。为了提高未来使用LC的通信技术的性能，仅从射频（RF）技术的角度来看是不够的。因此，在为下一代卫星和地面通信实现具有最高性能的先进射频器件时，不仅必须了解微波工程的新颖结构设计和优化，而且必须了解材料工程的视角。本文以先进向列液晶、聚合物改性液晶、双频液晶和光反应液晶为基础，总结和探讨了驱动改进的先进智能射频器件液晶的调制原理和重点研究方向。性能和新颖的功能。此外，还讨论了开发使用 LC 的最先进智能射频设备所面临的挑战。