The invention relates to a wideband wireless access technique, disclosing a bandwidth competing method in microwave access global intercommunication system, making it able to reasonably allocate competition time gap number, reduce signaling interactoin of air interface, reduce competition conflict number, and shortening conflict solving course and SS competition success time when implementing bandwidth competition of WiMAX system. By allocating different service grades for SS and separately defining corresponding multicast addresses to different-grade SS, it implements multicast group fixation to avoid signaling interaction in the multicast group establishing and deleting course, and besides, synthetically considers time gap number of the current frame, time gap allocation and transmission conditions of the previous frame and other information to determine competition time gap number of the current frame. |