1. A method of transmitting uplink scheduling grant information from a network node to a wireless device in unlicensed spectrum, the method comprising:performing a listen before talk (LBT) process on each of at least one carrier in the unlicensed spectrum;
transmitting the uplink scheduling grant information on one of the at least one carrier in response to a positive result of the LBT process on the one carrier, the uplink scheduling grant information being indicative of an uplink scheduling grant on multiple carriers in the unlicensed spectrum;
determining a metric for a plurality of carriers available in the unlicensed spectrum; and
selecting the multiple carriers based on the metric.