3D-printed artificial dielectrics for beam steering metasurfaces

Fused decomposotion 3D printing technology can be used to develop artificial dielectric meta-atoms that are not available commercially, with the advantage of low cost and little human intervention. A two-dimensional periodic arrangement of artificial dielectric meta-atoms forms a metasurface, which can serve as a platform to realise subwavlength-thick phase shifting (PS) structures. Such metasurfaces manipulate radio frequency (RF) waves and possess the ability to control the amplitude, phase and polarisation of the field. The objective of this thesis is to develop highly transmitting sub-wavelength sized 3D printable meta-atoms that can inculcate a full 2π phase shift in the transmitting field. These meta-atoms are then used to design transmitting beam steering metasurfaces. The meta-atom configuration developed uses one dielectric and two metallic layers. The dielectric permittivity and height are varied to achieve a full range of [0, 2π] while ensuring transmission levels remain greater than -0.75 dB. Moreover, meta-atoms are used to design beam steering surfaces for resonant cavity antennas (RCA) operating at 20 GHz. A peak gain of 21.65 dBi was achieved and the RCA pattern can be steered to any elevation between 0° and 35° with less than 2 dB gain variation.