Provided are space division multiple access for wireless local area network (WLAN), and channel estimation for the same. A frequency division multiple access technique and a space division multiple access technique based on competition are used together for channel access. The channel access method includes: a competition period for estimating channel characteristics for a plurality of stations and transmitting, to the plurality of stations, downlink schedule information or uplink schedule information based on the estimated channel characteristics; and a data transmission period for performing downlink transmission or uplink transmission with all or some of the plurality of stations in accordance with the downlink schedule information or the uplink schedule information.