Novel Low Loss Guiding Structure for High Frequency Applications

为了探索和利用从30 GHz到太赫兹（THz）的频率范围，迫切需要新的传输线路和测量技术。在这样的频率下，传统的传输线要么损耗太大，要么制造成本太高。拟议研究计划的目的是研究一种称为间隙波导的新传输线，该传输线将解决毫米波频率传输到潜在太赫兹的损耗问题。为这些特定应用量身定制的有效数值方法将在基于该技术的微波电路和散热器的分析和设计中得到开发和使用。这种新型缝隙波导的基本几何结构包括两个平行的导电金属板，它们被一个通常小于0.25导波长的小缝隙隔开。这个空隙可以用空气填充，也可以用电介质全部或部分填充。局部波出现在两个板块之间的间隙中。这些波是可以控制的，通过在两个金属板周围的纹理，迫使波从两个金属板迅速衰减。提出的技术将适应人工磁性导体的概念，并开发技术来提高其设计过程和工作带宽。到目前为止，通过简单的结构可以实现2:1的带宽，我们的目标是进一步改进和增强该带宽。人造磁性导体概念的另一个应用是在封装中，它将消除封装腔中损耗电阻片的需要，因为它目前是实践的。拟议的研究计划将对射电天文学、卫星通信、医疗成像以及安全应用中更高频率的使用产生巨大影响，因为与目前使用传统导向结构相比，其效率更高。

There is an urgent need for new transmission lines and measurements techniques in order to explore and exploit the frequency range from 30 GHz up to Terahertz (THz). At such frequencies, conventional transmission lines become either too lossy or too expensive to manufacture. The aim of the proposed research program is to investigate a new transmission line referred to as gap waveguide that will resolve the losses issue of transmission of millimeter wave frequencies to potentially THz. Efficient numerical methods tailored for these specific applications will be developed and used in the analysis and design of microwave circuits and radiators based on this technology. The basic geometry of the new gap waveguide comprises two parallel conducting metal plates, which are separated by a small gap which is typically smaller than 0.25 guided wavelengths. This gap can be filled with air or fully or partly filled with a dielectric. Local waves appear in the gap between the two plates. These waves are controllable by surrounding the two metal plates by textures from both sides that forces the waves to decay rabidly away from the two metal plates. The proposed technology will adapt the concept of an artificial magnetic conductor and develop techniques to enhance its design process and its operating bandwidth. So far a 2:1 bandwidth can be achieved with simple structures and we aim to further improve and enhance this bandwidth. Another application for the concept of an artificial magnetic conductor is in packaging, where it would eliminate the need for lossy resistive sheets in the packaging cavity as it is currently practiced. The proposed research program will have tremendous impact on the use of higher frequencies in radio astronomy, satellite communications, and imaging for medical as well as for security applications in terms of higher efficiency as compared with the currently achieved with conventional guiding structures.