CRFS blog

Evolving sensing for spectrum “sharing-native”

Written by Dean Bubley | Dec 5, 2024 6:42:58 PM

The future of wireless services of all types is likely to involve more spectrum-sharing and other more sophisticated approaches to spectrum assignment and management. That, in turn, will require more and better spectrum sensing as one of the key enablers.  

Today, key product segments such as spectrum databases, sensing tools, mapping solutions, specialised AI models, secondary spectrum marketplaces, and agile radio capabilities are viewed as distinct and separate technologies. Ideally, in the future, these spectrum management-related niches will eventually be recognised collectively as a unified technology category.

A recognised “advanced spectrum management” marketplace could help focus attention from vendors, governments, service providers, and investors. A regular and predictable cadence or cycle would further enable both awareness and adoption of new paradigms for spectrum.  

The future of spectrum management involves much more sharing 

Mobile services like 5G and 6G, satellite communications of various types, unlicensed spectrum for Wi-Fi or Bluetooth, fixed links, broadcast services, scientific radio observation, and assorted military, maritime, and aviation services will all need to coexist more tightly in the future, given inexorable demands for more spectrum across the board. It is increasingly hard to find “clean” bands to expand existing needs, add new use cases, or clear existing incumbents for a change of purpose. 

Regulatory authorities will increasingly need to actively manage and coordinate the time, location, direction, and power levels permitted for different users of the same band to maximise utility while minimising harmful interference. Sometimes, this may involve sharing between similar technologies, such as 5G vs. 6G, but often it will involve completely distinct ecosystems and waveforms. There will be considerable need for new forms of monitoring and enforcement, as well as mechanisms for opportunistic sharing. 

There needs to be as much emphasis on coexistence as on convergence, as sharing between organisations with entirely separate networks and no direct commercial interaction will be common. This is quite different from traditional multi-network models such as Wi-Fi offload or satellite/terrestrial mobile integration. 

Today, most spectrum-sharing regulatory schemes are fragmented by geography and band, usually driven by the specific needs of incumbents in a given market and the requirements of expected new uses. Such distinct sharing approaches imply customised design, test, deployment, and operation, with unique products and solutions. This fragmentation and one-off implementation approach reduces the speed and scope of spectrum-sharing adoption and deployment overall and requires “reinventing the wheel” many times.  

One scenario to explore for the future is an ongoing cycle of innovation relating to spectrum-sharing, with multiple sub-categories of enablers. This process could capture diverse requirements across different bands, countries/regions, and incumbent/newcomer types. It could also collect and disseminate the results of existing sharing models, allowing for collective improvement and learning. Regulators could use these products and systems as starting points for new sharing models. 

If there was a predictable cadence, perhaps via numbered releases or generations, it would be easier for suppliers, customers, academia, and policymakers to align, create a future pipeline, plan their R&D and product management, and create a broader ecosystem approach. Spectrum sharing could become more common, more effective, faster to implement, and involve lower costs. 

While full standardisation is unlikely in the short term, such an approach could allow closer alignment and scale economies, with progressive harmonisation over time. There will also need to be collaboration between a wide range of industry standards bodies (for instance, 3GPP and IEEE), market representation groups (GSMA, Wi-Fi Alliance, WBA, GSOA), and government / supra-governmental agencies in domains such as telecom, military, and aviation. There would also be important roles for ITU and regional regulatory authorities, either in acting as convenors of work or in capacity-building and skills development. 

The many technology sub-domains for future spectrum management 

A successful spectrum-sharing system requires many technical components. Many stakeholders are typically involved, including service providers, infrastructure owners, regulators, end-users, equipment and device suppliers, and software developers of multiple types. Some will involve dedicated products or subsystems, while others will need extra functionality added to existing products. 

Some of the areas that would be involved include: 

  • Spectrum databases, maps, and registries—both centralised and distributed, covering assignments, rights, and uses 
  • Spectrum sensing systems and associated data repositories, with various granularities, bands supported, and centralised/decentralised distribution models 
  • AI and analytics tools for optimising spectrum usage efficiency, allowing less-conservative restrictions on sharing where interference is more predictable, or for analysing real-world network usage patterns where it is dynamic 
  • Software-defined radio systems for both infrastructure and end devices 
  • Marketplaces or platforms for spectrum trading, leasing, or temporary assignments 
  • Cross-technology signalling solutions permitting different types of radio users to communicate their presence or requirements to others in a distinct ecosystem. 
  • Contextual awareness mechanisms for transmitters and receivers that may be able to infer or deduce that they are in specific locations, are indoor or outdoor, have particular lines-of-sight, etc. 
  • Automation tools and APIs for spectrum management systems. These could both enable more efficient administration by spectrum managers and easier applications for spectrum assignments and usage rights 
  • Test and measurement systems and processes 
  • Potentially, decentralised ledgers and blockchains acting as registries and/or transaction mechanisms for spectrum sharing 

  • Vertical applications based on dynamic spectrum access, in emerging fields such as transport, industry, healthcare, etc. 

An important facet of any future advanced sharing approach is the recognition that all the underlying technology enablers will continue to improve, often rapidly. Any future framework should be based on the expectation of continual evolution. This potentially means a rolling programme of standardisation and R&D, perhaps with some funding and goals from regulatory authorities.

This also implies alignment of spectrum-sharing with adjacent new technologies and industry standards, such as disaggregated networks or dealing with new radio techniques such as distributed MIMO, reconfigurable surfaces, and beam-steering. In particular, future 6G, Wi-Fi 8+, and new satellite technologies should be designed to be “sharing-native” and programmable wherever possible. 

Doing so could involve defining spectrum-sharing interfaces in the underlying 3GPP / IEEE / other standards, incorporating sensing functions and “polite” protocols, developing test cases, creating interoperability forums and workshops, and inviting new stakeholder groups into the processes at an early stage. Funding the replacement or upgrade of older systems to make them more “sharing-friendly” would also need to be considered. 

Certain technology elements may also be developed through open-source programs—especially the “platform” aspects such as databases, registries, spectrum trading/leasing, and user-facing applications and APIs. 

An early example of this trend is Open AFC1, a project by TIP (the Telecom Infrastructure Project) to develop an open-source implementation of the 6GHz AFC intended to allow unlicensed devices to use higher powers outdoors when granted permission by a database-driven system designed to protect incumbents. 

Conclusion 

Spectrum sharing will inevitably become more critical in the future. The current approach to creating customised technology solutions for each band/country is unsustainable. There needs to be more commonality, especially to allow sharing to scale to countries without huge local regulatory resources or skilled workforces capable of developing, testing, and operating sharing platforms. 

Creating a new category—and perhaps an industry association or standards body—for advanced spectrum-sharing enablers should be a priority for the world’s radio ecosystem. Such an approach could act as a multiplier for capital, R&D, skills, regulatory attention, and market awareness. There could be a positive cycle for spectrum users, vendors, regulators, and other stakeholders.