Active antennas with phased arrays are now universal in the world of satellites and are used in many different Microwave applications. The first application is telecommunications, which is certainly the leading one in terms of technology. They are also heavily used in Synthetic Aperture Radar (SAR) imaging, both for Earth Observation and Space Situational Awareness (SSA), as well as for Global Navigation Satellite System (GNSS) receivers on the ground and on satellite. Classical antennas (mechanical steered/fixed) or active antennas that utilize analog beamforming have been in use for many years. However, they present many drawbacks. That is why new architectures, based on digital beamforming, are emerging as future alternatives. They are more suitable to fulfil the structural requirements of the spaceborne equipment in contrast with the current analog, single aperture reflector antennas. Phased array antennas can have a light structure with a large aperture being more flexible and configurable. Other characteristics are high gain, long distance coverage, rapid beam scanning, agile beam steering, multibeam formation capability and easier maintenance (less hardware components and more software oriented).
The development of a new generation of Analog to Digital Converters (ADCs) with radiofrequency (RF) sampling rates, wide analog bandwidth and low power consumption is needed for the development of the next generation of digital phased array antennas, which will be integrated in future European satellites. ADCs are also listed as a priority by the European Commission for supporting the needs arising from EU space missions. High-speed ADCs are qualified as critical space technologies in the Technical Guidance Document for Horizon European Space Work Programme 2023.
