7. An eNode-B (eNB) for performing a backoff operation in a wireless access system supporting an unlicensed band, the eNB comprising:a transmitter;
a receiver; and
a processor configured to:
control the transmitter and the receiver to perform the backoff operation,
set a backoff counter value for performing the backoff operation,
when a current subframe corresponds to a backoff permitted duration, decrease the backoff counter value by 1 based on whether the unlicensed band is in an idle state or not after performing a carrier sensing (CS) operation in a CS unit,
when the current subframe does not correspond to the backoff permitted duration, maintain the backoff counter value without performing the CS operation, and
control the transmitter to transmit a reservation signal or data via a cell configured on the unlicensed band when the backoff counter value is zero.