Patent ID: 7492816

Claim:
A method of controlling compensation for loss in transmission of a data signal from transmitter circuitry to receiver circuitry comprising: transmitting a plurality of test signals in succession having known amplitudes and respective different frequencies; measuring amplitude of each test signal as received by the receiver; storing a plurality of values, for each test signal, indicative of whether the measured amplitude of the test signal is greater than or less than a predetermined threshold value; receiving a feedback signal from the receiver circuitry to adjust the predetermined threshold value when the measured amplitude of the test signal is less than the predetermined threshold value; and after the amplitude of each of the plurality of test signals is measured: analyzing the stored plurality of values for each test signal to identify at least one frequency where the predetermined threshold value has been adjusted to determine that unacceptable loss is occurring for the corresponding test signal; generating a transfer function based on the stored plurality of values for each test signal in response to identification of the test signal with the frequency at which unacceptable loss is occurring; and determining compensation based on the generated transfer function that will at least partly reduce the unacceptable loss.