Controlling microwave radiation from sources by design of their environment

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This project will investigate the use of metamaterials and metasurfaces for optimising antenna performance, such as efficiency and directivity. Other drivers in improving antenna design include the need to minimise weight, thickness and cross-sectional area, to extend bandwidth and reduce cost.The project will focus on the design of novel metasurfaces that impart artificial boundary condtions in order to achieve the ambitions above. Metasurfaces will be conceptualised, designed, modelled, fabricated and experimentally tested initially without reference to an antenna. Multilayered and multidomained designs will be considered that provide a broadband frequency response - this will likely requrie the minaturisation of the resonant elements within these surfaces, and this can be obtained by considering complex geomtries or the use of high-index materials. The second stage of the project will see the metasurfaces combined with the simplest radiator / antenna designs in order to understand the coupling between the two. The researcher will then develop the metasurfaces designs in order to match the current distribution in the radiating element, or to otherwise manipulate the antenna performance and functionality: this might include the consideration of anisotropic surfaces. Once this is undertsood, we will then consider more complex 'off-the-shelf' and bespoke designs of the radiating element in order to maximise the benefits of the combined surface-radiator antnnna system.The antennas of interest to Leonardo are very broadband covering tens of GHz similar - they find application in civil and defence applications such as wireless communication and aviation. The novelty of this studentship is in the application of metamaterials to optimise the antenna performance. It is quite possible that active or reconfigurable metamaterials are investigated or developed in the course of the studentship. Polarisation manipulation (to maximise the efficient use of the antenna aperture) is also of interest and within the scope of the project. In defence applications, radar cross-section (RCS) can also be important and so will also be considered for favoured antenna and metamaterial options.