Dual circularly polarized 2x2 antenna array for LEO satellite constellations

• Autor(a) principal: Fernandes, Ângela Rodrigues Jesus
• Data de Publicação: 2021
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10773/33697
• topic: Microstrip antennas; Aperture coupled feed; Antenna array; Circular polarization

Although communications technologies are in rapid development, there are still many remote regions that aren’t covered by telecommunication services. LEO satellite constellations are being used to address this issue by aiming to provide continuous and high-capacity global communication services. Satellite communications are usually made using frequencies near the Ka band, with higher frequencies for the uplink and lower frequencies for the downlink. The antenna developed in the course of this dissertation was chosen to operate at 20GHz, enabling its implementation for downlink communications. Furthermore, circular polarized antennas are useful in satellite communications for versatility by being able to receive other polarizations. The proposed antenna is a dual-fed square patch, with aperture coupled feed, incorporated with a quadrature hybrid coupler as the feed and later included in a 2x2 array. This antenna has the possibility of being left or right circularly polarized by choosing the feeding port. The structures presented were modeled progressively by simulation, in several stages, and so the evolution of the results could be analyzed as the antenna got more complex. After designing the antenna it was later fabricated, and measurements were taken for validation.