Secondary Cell HARQ Timing Derivation for eIMTA Carrier Aggregation

The patent applies local quality by differentiating HARQ timing determination between primary cells and secondary cells. For secondary cells with eIMTA enabled, a specific HARQ timing determination method is used that references the primary cell's HARQ timing, rather than applying the general SIB-1 configuration uniformly. This localized approach allows eIMTA performance to be maintained in secondary cells while preserving the standardized configuration approach.

The patent implements preliminary action by establishing the primary cell's HARQ timing configuration first, then using it as a reference to determine secondary cell HARQ timing. This pre-establishment of the primary cell's timing parameters allows secondary cells to inherit consistent timing relationships, ensuring eIMTA performance is maintained before data transmission begins.

The patent applies universality by creating a universal reference mechanism where the primary cell's HARQ timing configuration serves as the reference for all secondary cells, regardless of their individual SIB-1 signaled UL-DL configurations. This universal reference approach allows secondary cells with different configurations to maintain consistent HARQ timing relationships with the primary cell, enabling eIMTA performance enhancement without timing mismatch.

The patent uses the primary cell's HARQ timing configuration as an intermediary that mediates between the different SIB-1 signaled UL-DL configurations of secondary cells. This intermediary reference allows secondary cells to derive their HARQ timing from a common source, ensuring consistency across the carrier aggregation while supporting diverse eIMTA configurations.