The present invention relates to a method and apparatus, in which a station (STA) which operates in an available channel that is not used by a licensed device, detects a signal (hereinafter, referred to as ‘primary signal’) of the licensed device in a white space band, and operates in the available channel. According to the present description, the station receives white space map (WSM) information which contains available channel identification information from a device having database information; acquires the result of measurement for detecting the presence of the primary signal in a specific band range; and transmits, to another station, the WSM which is updated to contain information on the band in which the primary signal is detected, wherein the updated WSM further contains information which indicates whether each available channel in the updated WSM is based on the database information or based on the result of measurement.