Patent ID: 8457150

Claim:
A method for notifying status of a Mobile Node (MN) in a Wireless Local Area Network (WLAN) system using VLC, comprising: allocating a first predetermined number of time slots in a frame of time slots as unallocated slots, said unallocated slots assigned with providing status notification of an initially accessing MN and allocating a second predetermined number of time slots of said frame as reserved slots, said reserved slot assigned with providing status notification during initial access of an MN and uplink data transmission of other specific MNs, respectively, by an Access Point (AP) without interfering with uplink data transmission from other MNs in the WLAN; and transmitting a visible light signal representing status information of the MN in one of an unallocated slot and a reserved slot by the MN when the MN initially accesses the AP; wherein the visible light signal comprises a visible light carrier representing status information of the MN that is flickered to repeat a visible “on” period and a visible “off” period, a plurality of signal patterns are represented by controlling an interval between said visible “on” period and said visible “off” period and said visible light signal representing status information of said MN represents said status information of the MN by individually corresponding status information of the MN to said plurality of signal patterns; and terminating uplink data transmission in the reserved slot by the AP when the MN attempts an initial access to the AP and is to transmit the visible signal in a reserved slot.