Methods, systems, and apparatuses are described for wireless communications. In one method, an uplink grant may be received over a licensed spectrum. A clear channel assessment (CCA) may be performed in response to the uplink grant to determine availability of an unlicensed spectrum. The CCA may be performed prior to a transmission associated with the uplink grant. In another method, scheduling information may be received over a licensed spectrum. An uplink grant may be transmitted over the licensed spectrum. The uplink grant may be based at least in part on the scheduling information. The uplink grant may be configured to trigger a CCA to determine availability of an unlicensed spectrum prior to a transmission associated with the uplink grant.