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A low-profile multi-function antenna system suitable for small satellites is presented in this paper. The antenna system operates at UHF frequency band (400 MHz) and comprises eight miniaturised radiating elements (REs) based on a folded planar inverted-F antenna (folded PIFA) geometry. The REs are distributed (in sequential rotation) across two opposite faces of a metallic cube representing a typical small satellite body with dimensions of 0.5 x 0.5 x 0.5 m3. Their input impedances can be mechanically tuned to compensate for influence of the satellite body and possible nearby objects protruding the satellite surface. By appropriately feeding the REs, the antenna system can operate in three radiation modes: an omnidirectional mode providing a high coverage, a directional mode with substantial gain for data transmission, and a mode with four tilted beams for RF-tracking. Nominal polarisation in all the operation modes is circular.
Romain Christophe Rémy Fleury, Amir Jafargholi