Patent ID: 7787531

Claim:
A method of pre-distorting a predetermined data sequence to compensate for the impulse response of a channel over which the predetermined data sequence is to be transmitted comprising the steps of; transmitting the predetermined data sequence without precoding over the channel using a first transmitter, receiving the predetermined data sequence using a first receiver and equalising the received signal, using an algorithm that is constrained to optimise the equaliser specifically for the predetermined sequence, to enable the data sequence to be decoded; determining the equaliser coefficients required to enable the equaliser to equalise the received data sequence, applying the determined equaliser coefficients to a second transmitter; transmitting the equaliser coefficients to a second receiver using the second transmitter, receiving the equaliser coefficients at the second receiver, and loading the received equaliser coefficients into a precoder in the first transmitter when the predetermined sequence is subsequently transmitted so that it is received at the first receiver in a form suitable for decoding without equalisation at the first receiver.