Patent ID: 7187646

Claim:
A link quality determination unit for determining a link quality of a transmission link between an OFDM transmitter and an OFDM receiver of an OFDM transmission system, wherein: said link quality determination unit comprises a signal power variation determining unit adapted to determine the signal power variation of the reception signal in the receiver and at least a first link quality measure determination unit adapted to determine a first link quality measure representing the variation of the subcarrier signal power on the basis of the signal power variation as determined by the signal power variation determining unit; said link quality determination unit further comprising: a channel coefficient estimator which is adapted to determine estimates of the channel coefficients for the respective subcarriers; a signal power determining unit which is adapted to determine the signal power by averaging the power of the estimated channel coefficients over a plurality of subcarriers; and wherein: said signal power variation determining unit is adapted to determine, as the signal power variation, the signal power variance by determining the difference between the power of the estimated channel coefficients on the respective subcarrier and the signal power, by determining the absolute value of the difference, by squaring the absolute value of the difference, and by averaging the squared absolute value over a plurality of subcarriers.