Patent ID: 8005175

Claim:
A method of assigning a radio resource in an OFDMA-based wireless communication system, the method comprising: dividing the radio resource within a frame in a base station into localized assignment units and distributed assignment units, the localized assignment units comprising first subcarriers contiguous in both time and frequency, the distributed assignment units comprising second subcarriers assigned to a first mobile station and a second mobile station being serviced by the base station, wherein each second subcarrier assigned to the first mobile station is spaced apart in frequency from a neighboring second subcarrier assigned to the first mobile station by other second subcarriers configured to be assigned to the second mobile station; grouping the localized assignment units into a first zone and the distributed assignment units into a second zone; and assigning the first and the second zones to the frame, wherein the grouping and assigning mitigate inter-cell interference using an interference avoidance scheme and/or an interference randomization scheme, wherein the grouping and assigning comprises: defining at least one parameter for the first subcarriers within the first zone, the at least one parameter being defined to mitigate inter-cell interference, and loading the first subcarriers within the first zone and the second subcarriers within the second zone according to the at least one parameter, wherein a first OFDM symbol in the second zone is a last OFDM symbol in the frame, and wherein a next OFDM symbol in the second zone is not a OFDM symbol immediately preceding the last OFDM symbol in the frame.