QUALCOMM Incorporated
MESSAGE 2 REPETITION WITH TRANSMIT BEAM SWEEP AND ASSOCIATED BEAM REFINEMENT FOR MESSAGE 3 AND MESSAGE 4

Abstract:

This disclosure provides methods, devices and systems for random access procedures and beam refinement for wireless communications. A base station may repeat a transmission of a random access message 2 to a user equipment (UE) on a plurality of physical downlink control channel (PDDCH) candidates to improve reception of the random access message 2 and provide for selection of a refined beam. The UE may receive the random access message 2 on the plurality of repeated PDCCH candidates during a random access response window. The UE may select an offset based on a strongest of the plurality of PDCCH candidates. The UE may transmit a random access message 3 on resources indicated by the random access message 2 that are time shifted by the offset. The base station may select a beam for transmitting a random access message 4 based on the offset.