Abstract:In recent years, the commercial satellite industry has developed rapidly. From satellite IoT constellations to high-precision SAR imaging, the application fields of commercial satellites have become more and more abundant. Different from traditional large satellites, commercial satellites are mainly concentrated in the fields of micro-nano, Pina and other satellites, and the most common ones are 1U, 3U, 6U and 12U cube satellites. The size of the satellite platform is closely related to the payload communication capability. Due to the small size of satellite platforms such as micro-nano and Pina, the payload communication capability is seriously insufficient. How to increase the communication capability of the small satellite platform has become a key technical problem to be solved urgently for commercial satellites. The film antenna has the characteristics of being retractable and unfolding, and can be widely used in various small satellite platforms. Before launching into orbit, it can be folded within the size of the small satellite platform through a reasonable storage method. After in orbit，it is released by deploying the device to form a larger radiation aperture, effectively improving satellite communication capabilities. Due to the small thickness of the film (about 0.1 mm), the Q value is very high, which limits the bandwidth characteristics of the antenna, and it is not convenient to realize the circularly polarized radiation characteristics. Based on a flexible film (thickness of about 0.1 mm) and a conventional microstrip patch as a unit, the film antenna has better circular polarization and broadband characteristics through rotating array and multiple sequential rotation feeding. The scale is 16×8, the bandwidth of the antenna standing wave (VSWR≤2.0) and axial ratio (AR≤3.0 dB) can reach about 10 % and 4 % respectively, and the maximum normal gain can reach 24 dB, which significantly improves the work of the thin-film antenna.
