Briefly, the present disclosure is directed to methods and apparatus that allow for the synchronization with, and measurement reporting of, unlicensed frequency carriers. A method and apparatus for synchronizing to an Scell operating on an unlicensed carrier determine, at a UE (108, 116), one or more measurement instances where a discovery signal may be transmitted, for example, by a base station (132), on the Scell from a higher layer configuration message. The method and apparatus may monitor a control channel for a control channel message and determine whether the discovery signal will be transmitted during one or more measurement instances on the Scell. The method and apparatus may detect the discovery signal transmission on the Scell during one or more of the measurement instances. The method and apparatus may also synchronize to and/or measure the Scell based on detected discovery signal transmissions.