Patent ID: 7693032

Claim:
A communication method in an OFDM (Orthogonal Frequency Division Multiplexing) system, the method comprising: adapting modulation schemes, coding rates, pilot patterns, and power levels of a signal to produce an adapted signal, wherein: the adaptation process is performed in a transmitter; and the adaptation process is based on channel state information; generating, by the transmitter, a control information signal representing adaptation information, wherein the control information signal includes a single index value that refers to adaptation details of a modulation scheme, coding rate, pilot pattern, and power level; transmitting the adapted signal and the control information signal by the transmitter, separately or jointly; receiving the adapted signal and the control information signal by a receiver; looking-up the adaptation details from a look-up table at the receiver using the index value, wherein: the table includes multiple sets of adaptation schemes employed by the transmitter; and the number of pilot patterns associated with a particular combination of a modulation scheme and a coding rate is a function of how often the particular combination is used for transmission; measuring the channel state by the receiver, based on the received signals, wherein the measurements include: signal strength, average SINR (signal to interference plus noise ratio), variance in time, variance in frequency, variance in space, BER (bit error rate), FER (frame error rate), MSE (mean square error), or any combination thereof; and forming a probing sequence using the channel state measurements, computed channel quality information, or channel state measurements and computed channel quality information.