Loss Mechanism Analysis of the Solar Cell Waveguide Slot Phased Array Antenna Using Equivalent Circuit Method

This letter establishes an equivalent circuit model of the waveguide slot solar cell phased array antenna and the loss mechanism of its realized gain is successfully revealed. To validate the accuracy and validity of the equivalent circuit, a solar cell waveguide slot phased array antenna was designed. The fitted radiation efficiency curve by the established equivalent circuit is consistent with the measured curve, validating the correctness of the equivalent circuit. Moreover, we analyzed the impact of the equivalent circuit parameters on the radiation efficiency of the solar cell antenna. It shows that the radiation efficiency is mainly affected by the resonant state of the equivalent circuit of the solar cell part, and the radiation efficiency is the lowest when the working frequency meets the resonant frequency. The established equivalent circuit method can guide the design of high radiation efficiency solar cell antennas. The designed X band metal solar cell phase array antenna shows a high radiation efficiency of 69.5%-74%, and a high solar cell coverage ratio above 82%, which is suitable for satellite synthetic aperture radar (SAR) applications.