Solar-Powered Active Integrated Antennas Backed by a Transparent Reflectarray for CubeSat Applications

A gain-enhancement scheme that combines an active integrated antenna (AIA) and an optically transparent reflectarray on solar cells is proposed for CubeSat applications. As CubeSat antennas require a compact footprint, improving the gain over limited design space is challenging. The proposed gain-enhancement scheme exploits the distinct environmental feature of the space, namely, unlimited and sustainable solar energy. This energy is fed into a microwave power amplifier, which is cascaded with a quasi-Yagi antenna. This AIA approach can increase the gain by 22.7 dB. Furthermore, the AIA is arranged as the feed of the transparent reflectarray, which provides twofold advantages. First, the gain can be further improved by 11.0 dB; second, this transparent reflectarray is placed on already existing solar panels, so no additional clearance area is required. We organize the proposed scheme by three modules, including an AIA module, a reflectarray module, and a power management module. The proposed scheme is demonstrated by a prototype designed at 25.0 GHz. By fabricating the transparent reflectarray using Indium Tin Oxide printed on soda-lime glass, the proposed antenna provides realized gain of 41.3 dB with dimensions of 110 × 80 mm
²
; meanwhile, onboard electronics can still be activated due to the power management.