US Patent 11399393 Random access backoff indicator

A wireless device transmits, for a random access procedure, a first preamble via a cell comprising a first sub-band and a second sub-band. The wireless device receives a random access response. The random access response indicates a first backoff indicator indicating a first backoff time interval of the first sub-band. The random access response indicates a second backoff indicator indicating a second backoff time interval of the second sub-band. The wireless device determines a preamble retransmission for the random access procedure. The wireless device selects, as a backoff time interval, a shorter one of the first backoff time interval and the second backoff time interval. The wireless device performs, at a time based on the backoff time interval, a listen-before-talk procedure.