CSI Reporting in Unlicensed Wireless Systems

The patent segments the transmission power into different components: reference power (preset) and actual transmission power (dynamic). By separating these, the system can use reference power for CSI measurement while allowing actual power to adapt dynamically during LBT operations, thus resolving the contradiction between power adaptation and measurement reliability.

The patent introduces CSI scaling as an intermediary mechanism. The CSI is first measured using reference power, then scaled by the ratio of reference power to actual transmission power. This scaling factor acts as a mediator that transfers the effect of dynamic power changes to the CSI report without affecting the measurement process itself, maintaining measurement reliability while enabling power adaptation.

The patent applies local quality by selecting specific subframes for CSI measurement based on matching transmission power sequences. Instead of uniformly using all subframes, the system identifies local regions (subframes) with consistent power characteristics and uses only those for measurement, thereby improving accuracy while maintaining adequate coverage through the scaling mechanism.

The patent changes the parameter selection criterion for CSI measurement from simply availability of reference signals to matching transmission power sequences. By adding this parameter constraint, the system filters out subframes with inconsistent power characteristics, improving measurement accuracy while the scaling mechanism ensures adequate coverage is maintained.