QUALCOMM Incorporated
Timing advance signaling in a physical downlink control channel

Abstract:

Methods, systems, and devices for wireless communication are described. Generally, the described techniques provide for transmitting a first random-access channel (RACH) message and receiving a second RACH message that includes a timing advance command (TAC) in a physical downlink control channel (PDCCH). These techniques may be used by a user equipment (UE) or an integrated access backhaul (IAB) node to achieve time synchronization while limiting overhead. In one example, in an IAB network, an IAB node may transmit a first RACH message to a neighbor node, and the IAB node may receive a TAC in a PDCCH of a second RACH message from the neighbor node. In another example, in a beam failure recovery (BFR) procedure, a UE may transmit a first RACH message to a base station, and the UE may receive a TAC in a PDCCH of a second RACH message from the base station.