Patent ID: 7711386
Filing Date: 2010-05-04
Classification: H04L,H04W

Abstract:
1. A method for controlling downlink power transmitted from a base station to subscriber stations in a mobile communication system employing an Orthogonal Frequency Division Multiple Access (OFDMA) scheme, in which data is carried from the base station to the subscriber stations by subchannels to each of which a plurality of subcarriers are assigned, the method comprising the steps of: receiving, from the subscriber stations, an average of channel quality information of the plurality of subcarriers assigned to each of the subchannels together with information related to at least one subcarrier having a channel quality below a predetermined threshold, when a change in at least one of the average of channel quality information and the information related to the at least one subcarrier exceeds an allowed variance; calculating a transmission power for remaining subcarriers, excluding the at least one subcarrier having the channel quality below the predetermined threshold, among the plurality of subcarriers assigned to each of the subchannels based on a respective average of channel quality information and respective information related to the at least one subcarrier having the channel quality below the predetermined threshold, wherein the at least one subcarrier having the channel quality below the predetermined threshold is disabled and transmission power otherwise assignable to the at least one subcarrier is redistributed to the remaining subcarriers in each of the subchannels used for data transmission; and transmitting data through the remaining subcarriers in each of the subchannels based on the calculated transmission power.