Patent ID: 8457250

Claim:
A method performed at a transmitter for transmitting a multi-path orthogonal frequency division multiplex (OFDM) signal of a wireless transmission system using a plurality of antenna elements, the method comprising: detecting subcarrier frequency channel characteristics of the multi-carrier transmission; pre-equalizing a power of the plurality of subcarriers by dividing it by amplitude characteristics of the corresponding subcarrier frequency channel or all subcarrier frequency channels to compensate for a power profile of the channel(s); and transmitting the OFDM signal by using the pre-equalized subcarriers via said plurality of antenna elements, wherein the pre-equalizing comprises limiting an adjustment of a magnitude of the subcarrier signal to an upper threshold, stopping the pre-equalizing for a subcarrier signal for which the upper threshold is reached, and changing a modulation scheme for the subcarrier signal for which the upper threshold is reached.