Reconfigurable Antennas and Wave Processing Surfaces

该研究计划旨在开发新的可重构天线概念，以提高通信卫星反射面天线的性能和耐用性，以及雷达天线的波束控制能力，例如用于天气预报的天线。对于卫星天线，研究将集中在可选场的发射阵面上。其目标是能够通过在馈送系统中插入小型轻质平面多层表面来重新配置卫星在执行任务期间的覆盖区域。这些表面对入射到天线的主抛物反射面上的波施加了空间相位调制，因此起到了类似于主反射面成形的作用。这种重新配置卫星的地球覆盖范围可以延长其任务，并有助于可持续发展。通过对发射阵列进行更精细的控制，还有可能减轻卫星间干扰。与雷达天线有关的工作的目标是提出新的低成本技术，使波束扫描变得灵活。特别是，将研究插入到波导中的磁致动“钉床”结构，目的是实现一种能够在高水平射频功率下工作的低成本移相器。例如，有了这样的移相器，就有可能在天气预报机构使用的雷达中实现电子可控天线，并提高预测极端气候事件的能力。还将考虑在衬底集成电路技术中实现的反射光的重新配置和周期性加载的泄漏波导。

The proposed research program is aiming at the development of new reconfigurable antenna concepts that can enhance the performance and durability of telecommunication satellites reflector antennas and the beam steering capabilities of radar antennas such as those used for weather forecasting.For satellite antennas, the research will focus on field-selectable transmitarray surfaces. The objective is to be able to reconfigure the coverage zone of a satellite during its mission by inserting small lightweight planar multilayer surfaces in the feed system. These surfaces impose a spatial phase modulation of the wave impinging on the antenna's main parabolic reflector, and therefore play a role analogous to main reflector shaping. Such reconfiguration of a satellite's earth coverage can extend its mission and contribute to sustainable development. With a finer control on the transmitarray it would also be possible to mitigate inter-satellite interference.The objective of the work related to radar antennas is to propose new low-cost technologies that would allow agile beam scanning. In particular, magnetically actuated "bed-of-nails" structures inserted in waveguides will be studied, with the aim of realizing a low-cost phase shifter that can operate at high levels of radio frequency power. With such phase shifters, it would for instance become possible to implement electronically steerable antennas in radars used by weather forecasting agencies, and improve the capability to predict extreme climatic events. Reconfiguration of reflectarrays implemented in the substrate-integrated circuit technology and of periodically loaded leaky waveguides will also be considered.