METHODS FOR MSG-B IN TWO STAGE RACH Russian patent published in 2022 - IPC H04B7/06 

FIELD: wireless communication.

SUBSTANCE: invention relates to a method implemented by a wireless transmit/receive unit (WTRU) for beam failure recovery (BFR). To achieve the effect, the WTRU detects a beam failure in a serving cell, receives a set of reference signals corresponding to the set of beams, and determines information indicating a subset of the set of reference signals based on one or more measurements. The WTRU transmits a first message including a preamble and a payload, where the payload includes an index of each reference signal in the subset of the reference signals. The WTRU receives the second message, wherein the second message is a random access (RA) response to the first message, provided that the second message includes a WTRU Cell Radio Network Temporary Identifier (C-RNTI) identifying BFR success.

EFFECT: providing a reduction in the amount of downlink signaling.

14 cl, 12 dwg