A decision directed flicker noise canceller for reducing flicker noise in
a modulated input signal according to an embodiment of the present
invention includes a decision circuit, a conversion circuit, first and
second adders and a filter. The decision circuit provides signal
decisions based on the input signal. The conversion circuit provides
selected signal values based on the signal decisions. The first adder
subtracts the selected signal values from signals based on the input
signal to provide a flicker noise estimate. The filter receives and
filters the flicker noise estimate and the second adder subtracts the
filtered flicker noise estimate from the input signal and provides a
corrected input signal. In a feedback configuration, the second adder is
located in a feedback position before the decision circuit in the signal
processing path. In a feed-forward configuration, the second adder is
located in a feed-forward position after the decision circuit.