125 - Receiver Architectures and Beam Scheduling Strategies for Fused- PNT Concept

The current and future LEO satcom constellations operating in Ku and Ka bands are considering, along with the provision of the main communication services, also a native provision of positioning, navigation, and timing (PNT) services. Leveraging the existing satcom frequency bands and signals, the concept of such integration is referred to as Fused PNT, promising increased resilience and independence of the user segment from GNSS. Examples include Starlink, which already offers GNSS-free operation at the user level, OneWeb and Amazon Kuiper, for which PNT studies are ongoing. Provision of PNT service with 5G/6G Non-Terrestrial Networks (NTN) is also being actively investigated by 3GPP. The satcom signal coverage in Ku and Ka bands is achieved through highly directive spot beams. To ensures that the user can collect measurements from enough satellites for PNT (ideally 4 or more), a specific receiver architecture and a suitable beam scheduling strategy at the satellite level have emerged as some of the key enablers of the Fused PNT concept. PNT with a lower number of satellites, requiring multi-epoch processing, is also of interest, albeit the achievable performance is lower.

The objective of the activity is to study receiver architectures and suitable beam scheduling strategies and to develop a receiver prototype enabling the Fused PNT concept with 5G/6G non-terrestrial networks (NTN) in Ku and Ka bands, learning also from other satellite constellations designs.
This activity has been coordinated with activities run in the context of Horizon Europe.

The tasks to be performed shall include:

•  To study receiver architectures and solutions that enable Fused PNT concept with 5G/6G NTN, including among the others the 5G PRS signal, in Ku and Ka bands.
•  To perform a field campaign with OneWeb and Starlink downlink signals, and assess real-world PNT performance (possibly based on network-based differential PNT) for satcom mega-constellations and beam scheduling strategies.
•  To study suitable beam scheduling strategies at the satellite level that ensure that the user can collect measurements from enough satellites for PNT (ideally 4 or more).
•  To benchmark realistic satcom terminals in terms of number of beams and beam switching time, with a basic signal generator.
•  To prove the concept through development of a prototype receiver, verified in an anechoic chamber.

The main outputs of the activity will consist of:

•  Technical notes summarizing the field campaign, receiver architectures and solutions, and evaluation of different beam scheduling strategies matching the user capabilities.
•  Prototype receiver.
•  Validation report summarizing the results of benchmarks and achievable PNT performance.

It is noted that no Participating State expressed their opt-out for this activity (EL1-125).