In this thesis, three new antenna design approaches are introduced and investigated, for enhancing the performance of Internet-of-Things (IoT) systems. The approaches are based on novel pixel and mesh surface structures and form the core contributions of these thesis research.

In the first contribution, a new approach for designing compact MIMO antennas is proposed that is based on a pixel element surface which can be used in compact MIMO IoT receiver design for improving capacity. It is shown that optimizing the geometry of the pixelated surface can increase channel capacity by 13% and energy efficiency by 19.9% compared to the system without optimization. The importance of the approach is that it provides a direct link between communication and electromagnetic formulations of MIMO an...[ Read more ]

In this thesis, three new antenna design approaches are introduced and investigated, for enhancing the performance of Internet-of-Things (IoT) systems. The approaches are based on novel pixel and mesh surface structures and form the core contributions of these thesis research.

In the first contribution, a new approach for designing compact MIMO antennas is proposed that is based on a pixel element surface which can be used in compact MIMO IoT receiver design for improving capacity. It is shown that optimizing the geometry of the pixelated surface can increase channel capacity by 13% and energy efficiency by 19.9% compared to the system without optimization. The importance of the approach is that it provides a direct link between communication and electromagnetic formulations of MIMO antenna systems.

In the second contribution, a new approach for designing highly pattern-reconfigurable antennas is proposed based on a pixel surface. The antenna features of highly pattern-reconfigurable, 360° single and multi-beam steering ability, full 3D space scanning, planar geometry and compatibility with an FPGA controller makes it useful in various IoT applications such as wireless power transfer, RF sensing and analog precoding.

In the third contribution, a new approach for designing hybrid radio frequency (RF) and solar energy harvesting systems utilizing a transparent multiport antenna with a mesh surface structure is proposed. A key advantage of this approach is that the surface area of the solar cell is fully reused for the multiport antenna saving space. This work demonstrates the potential usefulness of increasing energy diversity in hybrid energy harvester for powering indoor IoT devices.