A method and a device in a node used for wireless communication are disclosed in the present disclosure. A first node transmits a first sequence and a first radio signal, the first sequence being associated with the first radio signal, the first sequence being transmitted on a first random-access channel, and a first bit block being used for generating the first radio signal; receives a second radio signal, the second radio signal comprising a first information block; and transmits a second sequence and a third radio signal, the second sequence being associated with the third radio signal, and the second sequence being transmitted on a second random-access channel, the first bit block being used for generating the third radio signal; the first information block comprises a first sequence index, the first sequence index corresponds to the first sequence.