Systems and techniques relating to interpreting signals on a channel
having an asymmetrical signal amplitude response. A signal processor,
such as a read channel transceiver device usable in a magnetic recording
system, includes an asymmetry correction circuit configured to receive an
analog signal and to compensate for asymmetry in the received analog
signal, a signal equalizer configured to receive an input signal
responsive to an output of the asymmetry correction circuit and to
generate an equalized signal, a discrete time sequence detector operable
to examine the equalized signal, and a control circuit that provides a
coefficient adjustment to the asymmetry correction circuit to affect the
asymmetry compensation based on an estimate of non-linearity derived from
the equalized signal and an output of the discrete time sequence
detector. The estimate can be a least mean squared estimate of the
non-linearity in the equalized signal.