The primary goal of this research is to investigate the existing photovoltaic antenna integration techniques and develop a new solar antenna integration topology in order to address the drawbacks of these techniques. With the increasing demands for low-profile antennas and a growing move towards the microgeneration of electricity, primarily by photovoltaics, photovoltaic antennas are of increasing importance with a growing amount of research in this area being developed. At present there are a number of designs for photovoltaic antennas which could be divided into two distinct categories. The first type is the use of solar cells as an RF ground plane, whilst the second type involves the use of solar cells as an RF radiating element. Both techniques bring significant challenges if they are to be widely adopted. Considering the first technique, using a solar cell as an RF ground plane introduces an optical shading problem, which significantly reduces the solar efficiency of the solar antennas using this integration topology. To this end, meshing the RF radiating element is investigated in this thesis to achieve optical transparency at the expense of increasing the cost and complexity of the fabrication process of photovoltaic antennas. Conversely, using a solar cell as an RF radiating element limits the ability to modify the resonance response using traditional RF bandwidth enhancement techniques due to the fact that solar cells need to have a homogeneous structure to achieve optimum solar performance. In order to address these challenges, a third solar antenna integration topology is proposed in this thesis. This method is based upon the use of solar cells as an RF stacked parasitic patch element suspended above the conventional RF radiating element of the integrated antennas. This integration topology enables the integrated solar cells to achieve an optimum solar efficiency due to their suspended position eliminating the shading problem. It also enables the RF radiating element to be modified to excite multiple TMmn propagation modes to achieve enhanced resonance response for multiband and wideband applications. This new topology has been further developed and applied to design a dual-polarised photovoltaic antenna for polarisation diverse communication systems, which has been extended to produce a photovoltaic array antenna for beam steering applications. This thesis addresses a major knowledge gap in the field of photovoltaic antennas. As a result of this, greater understanding of the design procedures of photovoltaic antennas and associated trade-offs from such designs is developed. Using this knowledge, novel designs that overcome the associated problems of current photovoltaic antennas are presented.
|Publication status||In preparation - May 2014|