Patent ID: 7570969
Filing Date: 2009-08-04
Classification: H04W

Abstract:
1. A system for controlling transmission power in a wireless local area network (WLAN), comprising: an access point having a transmission power controller, a first station and a second station each positioned in a service area of the access point, said access point receiving from said second station calculated link margin data of a third station positioned at a hidden node of the WLAN, when said second station is closer than said first station to said third station, said access point comparing the received calculated link margin data to preset link margin data to control the transmission power in the WLAN, the third station transmitting an authentication request to said access point and switching its mode from an infrastructure mode to an ad-hoc mode to send a beacon to the second station when said third station fails to receive an acknowledgment said access point, said second station, upon receipt of said beacon, calculating an average receive rate value of the third station and then calculating the calculated link margin data of the third station from its own link margin data and said average receive rate information and transmitting the calculated link margin data to the access point, said access point increasing power transmission to establish communications with the third station based on the calculated link margin data received.