Low-terahertz (Low-THz, 100 GHz-1.0 THz) technology is expected to provide unprecedented data rates in future generations of wireless system such as the 6th generation (6G) mobile communication system. Increasing the carrier frequencies from millimeter wave to THz is a potential solution to guarantee the transmission rate and channel capacity. Due to the large transmission loss of Low-THz wave in free space, it is particularly urgent to design high-gain antennas to compensate the additional path loss, and to overcome the power limitation of Low-THz source. Recently, with the continuous updating and progress of additive manufacturing (AM) and 3D printing (3DP) technology, antennas with complicated structures can now be easily manufactured with high precision and low cost. In the first part, this paper demonstrates different approaches of recent development on wideband and high gain sub-millimeter-wave and Low-THz antennas as well as their fabrication technologies. In addition, the performances of the state-of-the-art wideband and high-gain antennas are presented. A comparison among these reported antennas is summarized and discussed. In the second part, one case study of a broadband high-gain antenna at 300 GHz is introduced, which is an all-metal model based on the Fabry–Perot cavity (FPC) theory. The proposed FPC antenna is very suitable for manufacturing using AM technology, which provides a low-cost, reliable solution for emerging THz applications.

中文翻译：

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用于无线通信应用的宽带低成本和高增益低太赫兹天线综述

低太赫兹（Low-THz，100 GHz-1.0 THz）技术有望在未来几代无线系统（如第 6 代（6G）移动通信系统）中提供前所未有的数据速率。将载波频率从毫米波提高到太赫兹是保证传输速率和信道容量的潜在解决方案。由于低太赫兹波在自由空间的传输损耗大，设计高增益天线以补偿额外的路径损耗，克服低太赫兹源的功率限制显得尤为紧迫。近年来，随着增材制造（AM）和3D打印（3DP）技术的不断更新和进步，结构复杂的天线现在可以高精度、低成本地轻松制造。在第一部分，本文展示了宽带和高增益亚毫米波和低太赫兹天线的最新发展及其制造技术的不同方法。此外，还介绍了最先进的宽带和高增益天线的性能。总结并讨论了这些报告天线之间的比较。在第二部分，介绍了一个 300 GHz 宽带高增益天线的案例研究，它是基于法布里-珀罗腔 (FPC) 理论的全金属模型。拟议的 FPC 天线非常适合使用 AM 技术制造，为新兴的太赫兹应用提供低成本、可靠的解决方案。展示了最先进的宽带和高增益天线的性能。总结并讨论了这些报告天线之间的比较。在第二部分，介绍了一个 300 GHz 宽带高增益天线的案例研究，它是基于法布里-珀罗腔 (FPC) 理论的全金属模型。拟议的 FPC 天线非常适合使用 AM 技术制造，为新兴的太赫兹应用提供低成本、可靠的解决方案。展示了最先进的宽带和高增益天线的性能。总结并讨论了这些报告天线之间的比较。在第二部分，介绍了一个 300 GHz 宽带高增益天线的案例研究，它是基于法布里-珀罗腔 (FPC) 理论的全金属模型。拟议的 FPC 天线非常适合使用 AM 技术制造，为新兴的太赫兹应用提供低成本、可靠的解决方案。