Apple Inc.
CELL HANDOVER IN A RADIO CELLULAR SYSTEM

Abstract:

When user equipment (UE) is to be handed over, the network and/or the UE determines a best beam for the UE's interactions with the target cell before the handover is completed. One or more additional next best beams may also be determined. The network (e.g., the target cell) allocates one or more uplink (UL) grants that corresponds to the best beam. Via a current cell, the UE receives the one or more UL grants from the network pertaining to communications between the UE and the target cell. The UE determines whether any beams of the one or more UL grants satisfy beam criteria. The beam criteria may include 1) an allocated beam being the current best beam or 2) an allocated beam being within a strength threshold of the current best beam. If the criteria is not satisfied, the UE initiates another handover type (e.g., a RACH-based handover).