DC4 – Distributed Spectrum Sensing for Satellite Systems

1. MSCA Mobility rule

To be eligible for this PhD position, applicants must not have resided or carried out their main activity (work, studies, etc.) in the country of their first recruiting beneficiary (Germany or Spain) for more than 12 months during the 36 months immediately preceding the recruitment date — unless this period was part of a compulsory national service or a procedure for obtaining refugee status under the Geneva Convention.

2. Description of the Work Project

Frequency spectrum has become an extremely scarce resource for satellite systems. The growing
need to share this valuable asset with terrestrial wireless networks has significantly increased the
urgency for advanced radio resource management solutions. A highly timely example of this trend toward
greater spectrum coexistence is the effort by radio regulators to enable joint use of frequencies
allocated to both terrestrial Mobile Services (MS) and Mobile Satellite Services (MSS)—for instance,
in the context of direct-to-device connectivity use cases in fully integrated terrestrial/non-terrestrial
6G networks. While current radio regulations restrict access for secondary users in these bands,
future spectrum policies may establish symmetrical access rights for both terrestrial and satellite
systems. In this evolving context, spectrum sensing—the detection and localization of spectrum usage—
has emerged as a key enabler for flexible spectrum sharing strategies. Although collaborative
(or cooperative) spectrum sensing has been extensively studied in terrestrial networks, space-based
systems still face significant limitations in this regard. This PhD research will explore the potential of
a sparse array of satellite platforms, interconnected via inter-satellite links, to produce high-resolution
spectrum usage maps. Information exchange between satellites will be used to fuse sensing data and
to enable accurate localization of RF sources.

3. Core activities

1. Detailed definition of the considered scenarios, including relevant frequency bands, satellite orbits, interference patterns, channel impairments and on-board processing capabilities.
2. Design of collaborative spectrum sensing schemes, focusing on the collection and evaluation
   of sensing data at the individual satellite level and the fusion of this data to generate high-resolution
   spectrum usage maps in real time.