Advanced antennas for future wireless communication systems

无线通信系统的性能往往受到干扰、路径损耗、局部散射和多径传播的限制。因此，必须开发和部署可靠的天线系统，以提高未来无线通信系统的性能和效率。在这种背景下，具有超增益、辐射方向图可重构和宽带工作的下一代天线可以作为提高未来无线系统整体性能的有效解决方案。传统上，为了实现这一目标，使用了智能天线阵列。这种智能天线系统是基于传统的组合大量天线单元的设计策略。这些系统的后置是基于模拟或数字信号处理器，它们响应于接收到的信号自动优化辐射模式。这些方法的主要缺点是通过复杂网络馈送的天线数量很多，这导致由于损耗而降低了效率。 作为传统系统的替代方案，该研究计划旨在利用各种人工电磁材料，如有源频率选择表面(FSS)、电磁带隙(EBG)结构和超材料，开发一种新型的具有高增益、可重构辐射方向图的先进天线。其主要目标是设计和开发先进的新型天线，能够提供高增益、宽带操作和方向图可重构。为了实现这些吸引人的特性，我们建议开发新的可调谐有源FSS、EBG或超材料结构。通过控制这些结构的电磁特性，可以控制增益、频带和辐射方向图，并进行电子重新配置。这些先进的天线将能够极大地提高恶劣环境中的传输质量。有了这些特点，所提出的天线在未来的无线应用中具有巨大的潜力。为了实现这一具有挑战性的设计平台，拟议的研究将集中在人造电磁材料的研究和表征，包括灵活的FSS、EBG和超材料结构，以及它们在开发具有超增益、宽带和动态辐射方向图的新型先进天线中的应用。 在这项提议中，FSS、EBG和超材料结构提出了有趣的研究主题，因为它们具有不寻常的、通常未被探索的电磁特性。对这些人造材料有更深刻的了解，有望优化微波和毫米波天线的物理性能，也可能是掌握其他有前途的技术的关键。此外，在微波和毫米波尺度上控制结构合成的能力将导致具有前所未有的物理和电学性能的新功能材料的发展。 因此，该计划将有助于(I)分析、设计和实施与开发有源FSS、EBG和超材料结构有关的机制；(Ii)促进FSS、EBG和超材料结构及其在先进天线设计和开发中的应用方面高度集中的研究活动，以符合加拿大高科技行业的特定需求；以及(Iii)培养高素质的人员，以应对现代社会的科学和技术挑战。

The performance of wireless communication systems is often limited by interferences, path loss, local scattering and multipath propagation. Therefore, reliable antenna systems should be developed and deployed to enhance the performance and efficiency of future wireless communication systems. In this context, next generation antennas with ultra gain, reconfigurable radiation pattern and broad band operation can be used as an efficient solution for increasing the overall performance of future wireless systems. Traditionally, to achieve this objective, smart antenna arrays have been used. Such a smart antenna system is based on the conventional design strategy of combining large number antenna elements. The back-borne of these systems are based on analog or digital signal processors that automatically optimize the radiation pattern in response to the received signal. The principal drawbacks of these approaches are the high number of antennas fed through complex networks that leads to reduced efficiency due to losses. As an alternative solution to conventional systems, this research program aims to develop a new class of advanced antennas with high gain, reconfigurable radiation patterns using various artificial electromagnetic materials, such as active frequency selective surfaces (FSS), electromagnetic band gap (EBG) structures and metamaterials. The major goal is to design and develop advanced novel antennas that are capable of providing high gain, broadband operation and pattern reconfigurability. To achieve these attractive features, we propose the development of new tunable active FSS, EBG or metamaterial structures. By controlling the electromagnetic characteristics of these structures, the gain, frequency band and radiation pattern can be controlled and electronically reconfigured. These advanced antennas will be capable of drastically improving the transmission quality in hostile environments. With these features, the proposed antennas present significant potential for future wireless applications. To realize this challenging design platform, the proposed research will be focused on the study and characterization of artificial electromagnetic materials, including agile FSS, EBG and metamaterial structures and their applications in the development of new class of advanced antennas with ultra- gain, broad band width and dynamic radiation patterns. In this proposal, FSS, EBG and metamaterial structures present interesting research topics because of their unusual, often unexplored electromagnetic properties. A more profound knowledge of these artificial materials holds the promise of optimizing the physical properties of microwave and millimeter-wave antennas, and could also be the key to master other promising technologies. Moreover, the ability to control structural synthesis on the microwave and millimeter-wave scale will lead to the development of new functional materials with unprecedented physical and electrical properties. Therefore, this program will contribute to (i) analysis, design and implementation mechanisms involved in development of active FSS, EBG and metamaterial structures; (ii) foster highly focused research activities in FSS, EBG and metamaterial structures and their applications in design and development of advanced antennas , consistently with specific needs of the high technology Canadian industry, and (iii) train highly qualified personnel to respond to the scientific and technological challenges of our modem society.