2-in-1 smart panels: multifunctional structures with embedded patch antennas
This thesis evaluates the feasibility of an embedded antenna multifunctional structure (MFS) for spacecraft applications. The increasing commercialization and miniaturization of space missions call for versatile subsystems that make efficient use of limited spacecraft volumes. This research investigates a design for a microstrip patch antenna with an SU-8 photoresist substrate on a hybrid composite structural panel comprised of aluminum, carbon fibre composite (CFC) and polyethylene fibre composite (PFC) materials. While the proposed design does not outperform high-powered antennas such as reflectors, they can be utilized as secondary communication antennas for tracking, telelemetry and command (TT&C). In order to design and model the antenna in ANSYS HFSS electromagnetic simulations, all of the materials are characterized first. I performed a series of tests using parallel plate and microstrip devices to extract their electrical properties. After modelling and design, a manufacturing process for the substrate is optimized to work around the thermal constraints of the composite materials. The antenna is then deposited on top using a stencil and copper deposition methods. During the connector attachment process, the antenna prototype was subjected to rapid temperature changes which caused the SU-8 substrate layer and copper patch to crack in several places. The cracking introduced air gaps between the substrate and aluminum ground plane, and the microstrip patch was ammended by placing copper tape on top. After such repairs, the antenna prototype is then measured at an operational frequency of 2.5 GHz, with a -10 dB bandwidth of 60 MHz, and a peak gain of 1.45 dB. These results were followed by an investigation of various loss mechanisms. Although the resulting performance of the MFS antenna did not meet the expectations and criteria, there are still potential applications with my recommendations for future work in this research area that can improve the feasibility of this technology.
satellites, antennas, multifunctional structures, space accessibility, nanosatellites, spacecraft antennas