An approach is provided for supporting transmission in a multi-input-multi-output (MIMO) communication system including a plurality of terminals. A preamble portion of a frame is transmitted by a multiple transmit antennas of a hub using Orthogonal Frequency Division Multiplexing (OFDM) to the terminals over a channel, wherein each of the terminals determines a characteristic of the channel with respect to the transmit antennas as feedback information. The hub receives the feedback information from the terminals. The hub selects, according to the feedback information, a subset of the antennas for transmission of a remaining portion of the frame to the terminal.

Processing diversity signals includes receiving diversity signals at a number of antennas. The diversity signals have communicated information, and the antennas are associated with channel paths. A phase of at least one diversity signal is adjusted. The diversity signals are combined to form a combined signal. The combined signal is processed to yield the communicated information. A combined complex channel gain estimate is determined from the combined signal. An individual complex channel gain estimate is calculated for each antenna from the combined complex channel gain estimate. Phase adjustments associated with the channel paths are established according to individual complex channel gain estimates. The phase adjustments are applied to next diversity signals having next communicated information. The next diversity signals are processed to yield the next communicated information.

Determining a power control group boundary includes receiving a plurality of samples having power control groups, where each power control group corresponds to a time period. The following are repeated for a predetermined number of iterations: a window is set at a point of a sample; a number of power control bits within the window at the point is determined; and the window is moved to a point of a next sample. A point at which the window has the largest number of power control bits is identified. A power control group boundary is determined in accordance with the window at the identified point.

Adjusting a signal includes receiving signals and quality indicators at an adjuster. The quality indicators include as least one of a power control group boundary signal, a power control group index, a PN code per active finger, a reverse power control bit per active finger, an energy per chip over noise power spectral density ratio per active finger, channel estimates I/Q per active finger, an energy per bit over noise power spectral density, a transmit AGC signal, a total receive power, and any combination of the preceding. A signal adjustment is calculated according to the quality indicators, and the signals are adjusted according to the signal adjustment to yield adjusted signals.

One or more quality indicators are established at a first communication device having antenna elements. The quality indicators indicate a quality of one or more communication links between the first communication device and one or more second communication devices. A modification is determined according to the quality indicators, where the modification describes at least one adjustment of one or more modulation features. A time boundary indicator indicating a boundary of a time period is received. At least some of a set of signals are modulated in accordance with the modification and in response to the time boundary indicator, where a signal is associated with an antenna element. The set of signals is sent from the antenna elements to yield a transmitted signal.