According to some aspects, a first base station may communicate with a second base station (e.g. during a handover process) regarding support of new carrier types by a wireless device. The first base station may receive parameters from a wireless device via a legacy carrier indicating whether the wireless device supports a new carrier type, and information about these parameters may be transmitted to the second base station. The first base station may receive messages for configuring communications between the wireless device and the second base station, which may include identification of legacy carriers and associated new carrier type carriers. The configuration information may be transmitted to the wireless device and the second base station may communicate with the wireless device based on the configuration information.