Multibeam beamforming antennas for navigation

This thesis, titled "Multibeam Beamforming Antennas for Navigation" focuses on developing advanced antennas capable of beamforming in the L-band for Global Navigation Satellite System (GNSS) signals, aiming to enhance reliability and performance in diverse scenario. To achieve this, two innovative approaches have been implemented: a phased array antenna system and a modified 3D printed Luneburg lens.The phased array antenna system include the design of both the antenna array itself, from the sourceelement to the array structure and also the beamformer. The beamformer is composed of multiple stages inter connected by SMA connectors making the complete system extremely flexible and easy to modify. The beamformer is capable of generating multiple beams in the L-band, and can be used to track multiple satellites simultaneously. It's configuration includes a filtering and an amplification stages specifically for GNSS signals. The second technology developped is a modified 3D printed Luneburg lens. The final design of the lens allow the beamforming of up to 16 simultaneously active beams without any mechanical components and providing almost a full-sky view. Multiple versions of the lens and it's source array were developped including dual circular polarization and dual-band configurations. To be able to operate the lens, a custom 16 channel dual-band GNSS receiver was developped. The receiver is capable of tracking all the GNSS signals from all the existing constellations and can be used to track multiple satellites simultaneously. Finally, using the experience gained from the L-band, a Ku-band lens was developped. The lens is capable of generating multiple beams in the Ku-band and can be used to receive signals from recentlow earth orbits (LEO) constellations. The objective behind this lens for the European Space Agencyis to deevelop an alternative navigation system to the GNSS, relying on the signals from the LEO constellations.