UE Timing Advance Update for Layer 1/2 Triggered Mobility

The patent applies preliminary action by pre-configuring candidate cells with their timing advance values before the actual handover occurs. The UE stores TA values for multiple candidate cells in advance, so when handover is triggered, the UE can immediately apply the pre-stored TA value without performing random access procedure, thereby eliminating uplink interruption while ensuring synchronization.

The patent uses copying by having the UE store copies of timing advance values from multiple candidate cells during the configuration phase. These copied TA values are retained in the UE's memory and can be directly applied during handover to the target cell, replacing the need for real-time random access and eliminating transmission interruption.

The patent reduces complexity by performing the random access procedure only once during initial cell selection, and then storing the obtained timing advance values for multiple candidate cells. During subsequent handovers, the UE simply retrieves and applies the pre-stored TA values without repeating the random access procedure, significantly simplifying the handover process while maintaining synchronization reliability.

The patent applies universality by making the initially obtained TA value serve multiple purposes - it can be applied to multiple candidate cells during different handover scenarios. This multi-functional use of a single TA acquisition process eliminates the need for separate random access procedures for each candidate cell, reducing device complexity while ensuring reliable uplink synchronization across all candidate cells.