A wireless device transmits a first preamble via a first sub-band. The wireless device determines to perform a first preamble retransmission based on receiving no response to the first preamble. The wireless device selects, for the first preamble retransmission, a second sub-band. Based on the second sub-band being different from the first sub-band, the wireless device determines that a transmission power of the first preamble retransmission may be based on a same value of a power ramping counter used for transmitting the first preamble. The wireless device transmits, based on the transmission power, a second preamble for the first preamble retransmission via the second sub-band.