One general aspect of the present disclosure includes a device configured to operate in a wireless system. The device including: a transceiver configured with a plurality of Evolved UMTS (Universal Mobile Telecommunications System) Terrestrial Radio Access (E-UTRA) operating bands; and a processor operably connectable to the transceiver, the processer is configured to: control the transceiver to transmit an uplink signal via two bands among the plurality of E-UTRA operating bands, wherein the two bands are configured for uplink carrier aggregation (CA), and consists of a first band and a second band; and control the transceiver to receive a downlink signal via one or more band from the three bands among the plurality of E-UTRA operating bands, wherein the three bands are configured for downlink CA, are consists of the first band, the second band, and a third band.