ELECTROMAGNETICALLY QUIET SKIES - EXPRO+

Objective: To develop a tool for the prediction of satellites' unintended electromagnetic radiation on the ground telescopes and todevelop concepts to minimise the electromagnetic footprint of satellites.Description: The proliferation of an increasing number of satellites is making it harder for astronomers to execute their observations. Satellite unintended electromagnetic emissions generated by operating electronic equipment and as byproduct (spurious or out-of-band radiation) of intentional radio-frequency (RF) transmissions are being measured by astronomical observatories, also with increasingly sensitive detectors. This is potentially interfering with astronomical observations at their protected electromagnetic bands and is being exacerbated by the trends of satellite constellations flying at lower altitudes. The long-term objective is to protect radio astronomy, to preserve dark and quiet skies, whileallowing a sustainable future in space. Contributing to this, the activity seeks for the methods to predict and minimise the growing electromagnetic footprint caused by spacecraft. This activity is structured around two main tasks. The first is to define and create a base computational tool to predict the potential impact of satellites' unintended electromagnetic emissions on telescopes and other RF-sensitive sensors. This tool is aimed to be designed with a sufficiently generic framework to allow seamless integration into existing space debris simulation tools. The second task aims to develop technical measures for reducing the unintended emissions generated by electronic equipment and resulting from RF transmissions. In this component, the activity explores techniques to increase the electromagnetic and radio-frequency compatibility and improve the RF spurious performance, such as advanced shielding, filtering, noise-suppression strategies, adherence to stricter spectral masks, power and frequency control. Performance criteria and measurement techniques are also to be proposed to verify the reduced electromagnetic footprint. This activity encompasses the following tasks: - Survey of satellite emission data. - Development and prototyping of software to calculate the impact of satellite unintended emissions on observatories, with testing and benchmark measurements for verification. - Research and trade-off analysis of techniques for reducing unintended electromagnetic emissions. - Conceptual design of feasible and effective mitigation measures, with investigation supporting proof-of-concept and proposed performance criteria Software shall be delivered under an ESA Software Community Licence, so that any individuals or entities within ESA Member States can access to it and can provide update to the community of users.