A method and apparatus for wireless communication in the unlicensed spectrum between an eNB and UEs having different bandwidths, e.g., between a narrowband UE and a wideband eNB. A user equipment apparatus segments an uplink duration in each frame into multiple transmission units for each frequency, wherein a frame comprises an integer number of the transmission units. The apparatus transmits uplink communication based on the multiple transmission units, wherein each transmission unit comprises at least one on period and at least one off period corresponding to each of a plurality of frequencies, wherein during an on period the UE transmits uplink communication on the corresponding frequency and during an off period the UE refrains from transmitting uplink communication on the corresponding frequency. Each transmission unit may comprise multiple on periods and multiple off periods. The on/off periods may be configured by a base station or specified for each frame type.