Frequency spectrum remains the most valuable asset of the satellite communications sector and of the wider industrial base it supports. Whilst technologies, applications, and services have developed continuously throughout the decades that Satcom has been a viable commercial endeavour, the underlying methodologies for allocating and sharing RF spectrum between systems have not evolved at the same pace.
Spectrum allocations are still made pre-emptively by hand and are largely time-static with geographic boundaries, guardbands, and power emission limitations defined in order to isolate one service from another. This approach applies to controlling theinteroperability of separate Satcom networks, as well as controlling the inter-operation of satellite and terrestrial services. As communications demands continue to grow, this historic approach is constraining the roll out of new services and applications and is therefore expected to attract growing scrutiny in the coming years. Following pressure from the terrestrial telecommunications community, the use of the C-Band exclusively reserved for Satcom applications has come under focus in the last few years and the spectrum is now shared with terrestrial services in some parts of the world.
Recent announcements imply that parts of the Ka-Band previously used solely for Satcom will be soon be shared with terrestrial applications as part of the roll out of 5G networks. Reserved allocations solely for satellite communications services could ultimately become a thing of the past. As well as pressure from other service domains, the need for adequate spectrum to enable new Satcom applications and services to develop is apparent; frequency accesscurrently being a significant growth inhibitor to emerging Satcom M2M/IoT systems for example. Techniques are now being studied and developed elsewhere in the telecommunications field based on novel inter-system collaboration approaches and cognitive radio techniques to increase spectrum utilisation. In parallel, the deployment of flexible hardware, e.g. Software Defined Radio payloads, electronically scanned antennas, and flexible power amplification, as well as the development of Machine learning and Artificial Intelligence techniques, is creating the possibility of a major rethink in the approach applied to spectrum allocation. Applying such techniques in the Satcom domain would undeniably bring technical challenges to existing network operators, but also potentially bring benefits to end users and opportunities for better commercial exploitation by network operators and service providers. The scale of any improvements is however, not currently properly understood, both in terms of the increase in throughput achievable within existingnetworks, or by enabling new services to emerge.
The proposed activity will therefore comprise a detailed case study, with the goal of quantifying the potential improvement in utilisation that can be achieved by applying automated spectrum allocation techniques.Taking a specific Satcom frequency allocation by way of example, and using representative traffic patterns, the study will seek to simulate the improvements possible in terms of the total communication supported.
The study will:
- Identify scenarios that could benefit from dynamic frequency sharing strategies, based on both technical and economic aspects.
- Devise the best strategies to address each scenario, and select the most promising solution.
- Assess the performance of the given solution via simulation and test, and quantify the benefits that can be brought by such a solution.
The case study selected would consider scenarios consisting simultaneous operation of competing (uncooperative) services, as well as environments where cooperation between systems is defined and mandated, with incentives to all users to increase the utilisation factor. Differing philosophies will also be considered including allowing secondary spectrum users to operate provided they doo not interfere with primary users, as well as peer-to-peer sharing environments. Dependent on positive results, the principal outcomes of the study will be to establish a roadmap of the key technologies needed to be developed to make such techniques viable, and to identify the actions at regulatory or standardisation level that shallbe followed by the Agency to enable such framework.