Power control for retransmissions

A method comprising:

• determining, based on a first listen-before-talk (LBT) procedure for transmission of a first preamble of a first message, a busy channel indication;
• determining, based on a second LBT procedure and for transmission of a first transport block of the first message, a clear channel indication;
• transmitting, based on the clear channel indication, and using a first transmission power, the first transport block;
• determining that a time duration for receiving a response to the first transport block expired;
• ramping, based on the first transmission power, a second transmission power and a third transmission power;
• transmitting, using the ramped second transmission power, the first preamble;
• and
• transmitting, using the ramped third transmission power, a second transport block.

A method comprising:

• determining, by a wireless device, that a first random access channel resource, for transmission of a first preamble of a first message, is occupied;
• transmitting, via a first uplink channel resource sensed as clear, a first transport block of the first message;
• determining a power ramping counter value based on transmitting the first transport block and on not receiving a response to the first transport block;
• transmitting, via a second random access channel resource, and using a transmission power based on the power ramping counter value, the first preamble;
• and
• transmitting, via a second uplink channel resource, a second transport block.