On the Influence of Area Variations of the Photovoltaic ;Surface in Solar Cell Antennas

Some low power applications where antennas and solar cells are integrated into the same system have limitations and requirements imposed by the radiation characteristics that, usually, are fulfilled by varying solar cell physical parameters. The negative influences of those variations are not profoundly discussed in the literature that studies the extremely low-power systems, where radiofrequency and photovoltaic devices share the same structure. In this context, this work models a photovoltaic cell used as an antenna and analyzes the consequences of the solar cell area variation, imposed by the fabrication process of the radiating element. The parameters of the one-diode equivalent circuit model are extracted and used to simulated the I-V curves for different irradiance levels, validating the simulations with experimental measurements performed in the laboratory. Also, the solar cell fill factor, energy conversion efficiency, and current density are analyzed.