CBRS Interference Measurement Using Coordinated Blank OFDM Symbols

The patent introduces a Radio Measurement Controller (RMC) as an intermediary entity that coordinates interference measurements among multiple CBSDs. The RMC manages the scheduling of Coordinated Blank OFDM Symbols (CBOS) and collects interference measurement reports, acting as a central mediator that enables precise interference measurement without requiring direct complex coordination between all CBSDs. This resolves the contradiction by providing centralized coordination that improves measurement precision while managing system complexity through a dedicated control entity.

The patent implements preliminary coordination where the RMC schedules CBOS in advance and notifies participating CBSDs before the actual interference measurement occurs. The blanking configuration and measurement opportunities are predetermined and communicated to CBSDs beforehand, allowing them to prepare their measurements. This preliminary action enables precise interference measurement while reducing real-time coordination complexity, as the critical coordination decisions are made in advance rather than during active measurement.

The patent applies partial action by implementing coordinated blanking only for specific neighboring CBSDs that are identified as potential interferers, rather than blanking all CBSDs in the system. The RMC selectively schedules CBOS for CBSDs that need to perform interference measurements on specific frequencies, leaving other CBSDs to continue normal service. This partial coordination approach achieves sufficient interference measurement precision while minimizing overall service interruption time across the network.

The patent implements periodic interference measurements using scheduled CBOS rather than continuous blanking. The RMC periodically allocates CBOS resources for interference measurements at predetermined intervals, allowing CBSDs to resume normal service between measurement periods. This periodic approach maintains measurement precision by regularly capturing interference conditions while significantly reducing the total time that services are interrupted, as blanking occurs only during brief measurement windows rather than continuously.

The patent segments the interference measurement process by dividing the system into measurement groups managed by a central RMC. Each CBSD is assigned to specific measurement groups and frequencies, and the RMC schedules CBOS for different groups at different times to avoid mutual interference. This segmentation allows multiple CBSDs to perform measurements simultaneously within their designated groups while preventing cross-group interference, thereby maintaining measurement coverage without making coordination infeasible.

The patent implements dynamic scheduling where the RMC adaptively assigns CBOS resources and measurement opportunities to CBSDs based on current network conditions, interference patterns, and service requirements. The coordination scheme is not static but dynamically adjusted to optimize both measurement coverage and minimize coordination complexity. This dynamic approach enables multiple CBSDs to perform measurements simultaneously when conditions permit while automatically preventing conflicts when mutual interference would occur, maintaining ease of operation despite multiple concurrent measurements.