User equipment (UE)-triggered handover with early preparation in mobile networks

Methods and apparatus are provided for UE-triggered handover and early preparation with coexistence of the network-triggered handover. In one novel aspect, the UE is configured early measurement report configuration, receives an early handover command from the serving base station with a handover candidate cell list, monitors handover triggering conditions for each candidate cell on the handover candidate cell list based on a UE-triggered handover configuration and performs the UE-triggered handover to a candidate cell when the corresponding triggering condition is met for the candidate cell. In one embodiment, the UE receives a network-triggered handover command to a target cell, suspends the UE-triggered handover configuration and performs the network-triggered handover to the target cell. The UE discards the UE-triggered handover configuration upon success of the network-triggered handover and resumes the UE-triggered handover configuration upon failure of the network-triggered handover.