Abstract This article presents the design and analysis of 4-hexyl-4′-biphenylcarbonitrile (6CB) nematic liquid crystal (NLC)–based rectangular patch antenna for S-band and C-band communication applications. Two glass substrates with permittivity of 6.4, loss tangent of 0.01 and thickness of 1 mm each with 21 × 25 mm2 and 19 × 19 mm2 dimension has been used, and 0.005 mm air gap has been placed to fill 6CB NLC. A rectangular patch of 10 × 11 mm2 size has been considered over the top substrate to achieve the application specific bands. The designed antenna model-1 with air gap is resonating at 5 GHz (4.01–7.85 GHz) with minimum S 11 of −24.2 dB. The proposed antenna model-2 is filled with 6CB NLC in the air gap between glass substrates is resonating at 3.3 GHz (2.61–4.45 GHz) with minimum S 11 of −29.75 dB. Antennas of both air gaps filled, and liquid crystal material filled models are fabricated and tested through combinational analyser for validation. The correlation between transmitted and received signals of the antenna models are analysed with time domain analysis by taking the identical antennas in face to face and side by side condition. The simulated results from HFSS electromagnetic tool and fabricated antennas results in chamber are exhibiting good agreement with each other.

中文翻译：

---

用于S波段和C波段应用的6CB向列液晶矩形贴片天线的设计与分析

摘要 本文介绍了用于 S 波段和 C 波段通信应用的基于 4-己基-4'-联苯甲腈 (6CB) 向列液晶 (NLC) 的矩形贴片天线的设计和分析。使用了两个介电常数为 6.4、损耗角正切为 0.01 且厚度为 1 mm 的玻璃基板，每个玻璃基板的尺寸为 21 × 25 mm2 和 19 × 19 mm2，并放置了 0.005 mm 的气隙以填充 6CB NLC。已考虑在顶部基板上放置 10 × 11 mm2 大小的矩形贴片，以实现特定应用的波段。设计的具有气隙的天线模型 1 在 5 GHz (4.01–7.85 GHz) 下谐振，最小 S 11 为 −24.2 dB。建议的天线模型 2 在玻璃基板之间的气隙中填充 6CB NLC，在 3.3 GHz (2.61–4.45 GHz) 下谐振，最小 S 11 为 -29.75 dB。两个气隙的天线都被填充，并通过组合分析仪制作和测试液晶材料填充模型以进行验证。天线模型的发射和接收信号之间的相关性通过采用面对面和并排条件的相同天线进行时域分析。HFSS 电磁工具的模拟结果和室内制造的天线结果显示出良好的一致性。