US Patent 7164648 Ultra high speed crosstalk cancelling technique

An ultra-fast crosstalk cancellation technique characterizes crosstalk with a sample set representing NEXT generated by a single transmitted bit. During operation, transmit bit values of transmitted bits are saved in a transmit bit shift register and used to weight crosstalk samples corresponding to a stored transmit value. The weighted transmit samples are summed to generate a crosstalk cancellation signal which is subtracted from a received signal to remove NEXT.