الفهرس 
2.2. THREE-DIMENSIONAL METAMATERIALS
MULTIFUNCTIONAL METASURFACEOnly 14 pages are availabe for public view
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Abstract
This thesis aims to introduce easily manufacturable metasurfaces that achieve high performance for microwave applications. This thesis aims to clarify the behaviour of cross-junction based metasurfaces. It also aims to discuss the behaviour of single layered and double layered structures, and the effect of breaking the structural symmetry of the unit cell by rotating the second layer. Furthermore, the thesis aims to introduce an application of the double layered metasurface as a polarization rotator and optimize the performance to achieve maximum bandwidth and minimum insertion loss with efficient polarization rotation. Additionally, other applications are introduced, which are multifunctional metasurfaces that allow for simultaneous polarization conversion and beam steering or beam focusing of the transmitted wave.
The thesis is divided into five chapters as listed below:
Chapter 1:
This chapter introduces the background, motivation, objectives, major contributions, and organization of the thesis.
Chapter 2:
This chapter reviews the history of metamaterials and especially metasurfaces. It details the different categories of metasurfaces, and discusses some of its applications, such as frequency selective surfaces, polarizers, and beam steerers. It also goes into the Fano-resonance phenomenon and how it could be utilized to improve the performance of the structure.
Chapter 3:
This chapter studies the cross-junction based metasurface. It goes into the details on how the electromagnetic wave interacts with the unit cell and studies the effect of breaking the symmetry of the structure. It also presents a two-layered unit cell with a complete analysis of the wave interaction with the unit cell. Additionally, a rotation is added to utilize the metasurface as a polarization converter, that rotates the linearly polarized incident wave to the orthogonal polarization. The structure was manufactured, and the measurements and simulations have shown strong agreement.
Chapter 4:
This chapter introduces other functionalities to the designed metasurface, which is beam steering and beam focusing of the transmitted wave. A full design for four different surfaces that can achieve different steering angles based on the phase progression of the unit cells is presented. Simulations for the different surfaces is presented, validating the design for the specified beam steering angle. A meta-lens has also been designed to achieve beam focusing at a specific focal length, and the simulations agreed with the designed specifications.
Chapter 5:
This chapter provides a conclusion to the executed work and suggests future research directions.