8TX Uplink MIMO Codebooks With 4-Port Mapping

The patent segments the 8-port codebook into multiple 4-port codebooks, where each 4-port codebook handles a subset of antenna ports. This allows the system to support 8-port transmissions by combining results from multiple simpler 4-port codebooks, thereby maintaining low device complexity while achieving high adaptability.

The patent extends the codebook structure from 4-port to 8-port by adding another dimension (antenna port dimension). Instead of creating a completely new complex 8-port codebook, it reuses existing 4-port codebooks and combines them through additional indexing and selection mechanisms, effectively transitioning from a 4-port to an 8-port system while managing complexity.

The patent creates a universal codebook structure that can handle both 4-port and 8-port transmissions using the same fundamental 4-port codebooks. By making the 4-port codebooks multi-functional (capable of serving both 4-port and 8-port scenarios through different indexing and combination strategies), the system achieves high reliability for advanced UEs without proportionally increasing complexity.

The patent performs preliminary organization of precoding matrices in 4-port codebooks that can be later combined for 8-port operations. By pre-computing and structuring the 4-port codebooks in advance with appropriate indexing schemes, the system prepares the necessary components for 8-port transmissions, reducing the complexity of real-time precoding operations for advanced UEs.