A wireless access point includes a memory and a processor. The processor is configured to access instructions stored in the memory, and execute the instructions to perform following steps: periodically transmitting a plurality of beacons to a station so that the station operates in a low power sleep mode or an active mode based on the beacons, in which the beacons includes two successive beacons; and, between the transmission of the two successive beacons, determining whether to transmit a management frame to the station based on a traffic condition of packets being directed to the station so that the station establishes a mode switching in response to the management frame. The traffic condition includes a channel state and a number or a validity of the packets. The mode switching includes switching from one of the low power sleep mode and the active mode to another.