In a wireless local area network (WLAN) system, a transmission STA can transmit a PPDU via a 320 MHz channel, and a Medium Access Control (MAC) signal may be generated for the PPDU. The MAC signal may include puncturing pattern information and channel center frequency segment (CCFS) information for a 320 MHz band. The CCFS information may include a first CCFS field related to channel center frequency (CCF) information of a primary 160 MHz channel, and a second CCFS field related to CCF information of a 320 MHz channel.