Patent ID: 8040831

Claim:
A method comprising: at a base station, dividing a coverage area into a number of segments; assigning a unique set of transmit subcarriers from a plurality of subcarriers for multiple subcarrier transmission to each of the segments; applying beamforming to each of the unique sets of transmit subcarriers to form a transmit beam pattern for each segment, wherein each unique set of beamformed transmit subcarriers has control information carried in a subset of subcarriers within a corresponding unique set of beamformed transmit subcarriers; and transmitting a different predetermined preamble to each of the segments using a corresponding unique set of beamformed transmit subcarriers, wherein each different preamble is configured to indicate to a subscriber station a spectrum location of the subset of subcarriers carrying the control information within the corresponding unique set of beamformed transmit subcarriers; and receiving a response from a subscriber station indicating a selected preamble detected at a highest power level by the subscriber station.