Precoding Matrix Index Selection for Non-Adaptive HARQ in MIMO Systems

The patent applies preliminary action by having the UE store precoding matrix information from previously received scheduling grant signals before they are needed for retransmission. When a scheduling grant is not received, the UE can retrieve and use the stored precoding matrix information from earlier transmissions, eliminating the need to receive updated scheduling grants for every retransmission while maintaining accurate precoding information.

The patent implements self-service by enabling the UE to autonomously retrieve and reuse stored precoding matrix information from its own memory when scheduling grant signals are not received. This allows the UE to maintain accurate precoding information for retransmissions without requiring continuous external provision of scheduling grants, thus improving retransmission efficiency while preventing information loss.

The patent applies segmentation by organizing precoding matrices into distinct groups or sets, where each group contains precoding matrices suitable for specific transmission scenarios or channel conditions. This structured segmentation allows the UE to efficiently select appropriate precoding matrices based on current conditions without managing a single large undifferentiated set, thereby improving adaptability while controlling complexity through organized storage and selection mechanisms.