A method performed by a user equipment (UE) is described. The method includes receiving a physical cell identifier information element (IE) from an evolved node B (eNB). The physical cell identifier IE is associated with a secondary cell (SCell) that is on an unlicensed Long-Term Evolution (LTE) carrier frequency. The method also includes determining a physical-layer cell identity (PCI) of the SCell based on the physical cell identifier IE. The method further includes applying the PCI as a parameter for physical channels or signals on the SCell.