A first base station receives, from a second base station, at least one listen before talk (LBT) parameter based on one or more results of one or more LBT processes performed by the second base station on one or more unlicensed cells. Based on the one or more results of the one or more LBT processes performed by the second base station transmit, a request for a handover of a wireless device to the second base station is transmitted to the second base station. A response confirming the request for the handover is received from the second base station.