Method and apparatus for multi-channel operation in wireless local area network system

A wireless apparatus, comprising:

• a radio frequency (RF) unit which transmits or receives a frame;
• and
• a processor which operates while operably connecting with the RF unit,
• the processor being configured for
• transmitting operating channel information and channel activity information to a plurality of stations (STAs), wherein the operating channel information is for indicating at least one of a first channel and a second channel as the at least one operation channel to each of the plurality of STAs, and the channel activity information is for indicating an activity duration where the AP transmit or receive a frame through each of the first channel and the second channel;
• and
• transmitting or receiving a frame through the first channel or the second channel on the basis of the channel activity information,
• wherein the channel activity information includes:
• a channel indicator,
• an activity offset indicating a point of time when the activity duration first starts for a channel indicated by the channel indicator,
• a length of the activity duration, and
• an interval between the activity durations.