Spectrum Coordination R&D Topics

The NIST CTL’s spectrum coordination research and development efforts focus on enabling, and ultimately maximizing, spectrum sharing. We do this by improving the understanding of how federal, commercial and unlicensed users can best use a given slice of the airwaves at a particular place and time.

Coordinating dynamic, automatic spectrum sharing involves developing innovative protocols and architectures to allow prioritized use of a particular channel or channels by disparate systems, either through distributed or centralized management. NIST CTL’s spectrum coordination work includes:

• Performing assessments of proposed spectrum coordination technologies – including both centralized, database-driven approaches and fully-distributed, “cognitive radio” solutions – drawing on technical literature, emerging standards, and policy initiatives
• Determining the architecture, interface specifications, and representative implementation of a Spectrum Access System (SAS) for centrally-coordinated sharing of a radiofrequency band. This work depends on dynamic centralized coordination using real-time sensing.
• Developing methods for protecting sensitive operational characteristics of incumbent systems
• Creating distributed-coordination algorithms in which cognitive radios use spectrum sensing to detect and exploit white spaces opportunistically. The NIST CTL’s prior work in cognitive radio algorithms, which have focused on statistically deriving upper bounds on the probability of collision or on the duration of interference, are informing this effort.

Future work will investigate spectrum coordination techniques that achieve higher secondary-system utilization and spectrum efficiency while maintaining the same level of incumbent system protection. Part of this work will include the dynamic determination of protection zones, which will combine propagation models including terrain, clutter and building vector data to predict where lower-priority users would interfere with incumbent systems.