Spacecraft Beacons: radiocommunication approaches towards interoperable autonomous self-identification and tracking

The ongoing Smallsat (r)evolution related to strongly increasing numbers of launches, failures and reduced sizes, raises issues regarding the detection and identification of space objects for the overall Space Situational Awareness (SSA), future Space Traffic Management (STM) but also for the individual spacecraft operators themselves. This paper gives an overview describing the challenges as well as proposed tacking aids for spacecraft and debris, focusing on active radiocommunication solutions. Following a motivation for beacon transmitters, known approaches to date will be discussed. Furthermore, the paper describes the current work of the authors, highlighting the scope of the BEECON (Berlin Experimental and Educational Beacon) project by Technische Universität Berlin (TU Berlin). Those activities are not designated to specific technologies but are currently aligned with open source technical approaches by the Libre Space Foundation (LSF), working towards the in-orbit verification of a spread spectrum identification and Doppler tracking solution called Satellite IDentification and LOCalization (SIDLOC). This collaborative work comprises the technical development, manufacturing, integration and in-orbit testing, using ride-shares on different missions. Finally, the work also includes the important path of regulatory and harmonization work towards future interoperable frequency bands and interfaces.

This paper is based on a presentation which was initially given at the ESA Clean Space Days 2024 at the European Space Research and Technology Centre (ESTEC) in Noordwijk, Netherlands.