Abstract

With the spread use of solar cells as a renewable energy source and the wide use of wireless communications, it is interesting to use the solar cell panels as an energy source for rural wireless communications for security and safety. For compactness, it is proposed to embed antennas in the solar cell panels. Therefore, it is proposed to investigate the antenna characteristics within this environment. As such, the characteristics of the solar cells in the radio frequency region should be studied for proper design of the antennas in such an environment. Therefore, a rigorous design approach for antennas in the solar cells' environment is proposed through this work. A practical model of the solar cells in the microwave frequency range is presented using anisotropic surface impedance boundaries. Two different surface impedance measurement setups are exploited to accurately model solar cells. Moreover, measurements of antennas' radiation efficiency are invoked in this work using the Wheeler cap concept in a contactless fashion to perform measurements within solar cells' environments. A novel measurement technique has been proposed extending conventional Wheeler cap capabilities to measure wide band antennas. The technique promotes a straightforward processing procedure and convenient measurement setup.


In addition, a simple, fast, and efficient numerical solution for the electromagnetic scattering arbitrary problems is proposed. Based on the uniqueness theorem and the use of novel equivalent problems with Random Auxiliary Sources (\emph{RAS}), more degrees of freedom are added resulting in significantly faster solutions. The proposed technique is expected to provide a significant reduction in the execution time and memory requirements compared to the surface equivalent based Method of Moments (MoM) as the inherent properties of this procedure are used. Various verification and result cases are presented to assess the introduced technique, which is incorporated into different analysis and design problems in this work. Moreover, the RAS method is extended to model antennas in their radiating and scattering modes, which, in turns, is adopted in the reflectarray antenna analysis and design procedures.

The introduced solar cells models along with the developed computations and measurement tools are used to develop a design procedure for antennas suited for the solar cells environment. An optically transparent reflectarray antenna integrated with solar cells is proposed as an application of interest that suits satellite communication purposes. Material choice, feed antenna tailored design and rigorous design procedures are presented to enhance the achievable performance of the antenna/solar cells integrated device.