The method and device access channel

Access channel provides a method and apparatus according to the present invention, the method comprising: receiving a first transmission side apparatus competition sent on the M subcarriers request frame, the M sub-carriers in at least two discrete sub-carriers, the competition request frame transmitted by the first terminal device to modulate the M sub-carriers; request frame transmitting device acquires the first channel state information on each of the M sub-carriers based on the competition, for determining the first device transmitting end channel state information separately on N subcarriers, the N sub-carriers is available to all or part of the system band division obtained, the N sub-carriers comprising M sub-carriers, N, and M are positive integers, N> M and M> 1; subchannels allocated transmission side apparatus according to the first transmitting channel state, respectively, on the N subcarriers information. Thus, the effective use of channel resources, increase the throughput of the system, multi-user selection gain.