Channel State Information Reporting With Adaptive Codebooks

The channel state information is segmented into multiple codebook types (first codebook and second codebook), where each codebook serves a specific function. The first codebook contains precoding matrices for spatial filtering, while the second codebook contains phase compensation values. This segmentation allows the system to transmit precise channel state information by selectively combining codebooks based on channel conditions, thereby improving precision without always incurring maximum feedback overhead.

The patent implements partial action by allowing the terminal to report channel state information using only the necessary codebook(s) depending on the channel scenario. When the channel does not require phase compensation, the terminal reports only from the first codebook, reducing overhead. When phase compensation is needed, the terminal reports from both codebooks, achieving higher precision only when necessary. This resolves the contradiction by making precision adaptive rather than constant.

The system dynamically adapts the channel state information reporting strategy based on channel conditions and configuration information. The network can configure different codebook combinations and reporting modes, allowing the precision of channel state information to be dynamically adjusted according to actual needs. This dynamic approach ensures that feedback overhead is minimized while maintaining adequate precision for the current channel conditions.

The patent changes the parameter representation by introducing a two-stage codebook structure where the first codebook parameter represents spatial filtering and the second codebook parameter represents phase compensation. By changing how channel state information is parameterized and reported, the system achieves efficient compression of channel state information, reducing feedback overhead while preserving the essential precision needed for effective beamforming and spatial multiplexing.