Patent ID: 7693215

Claim:
A circuit, comprising: a filter to produce an output based on an input that represents a symbol being received, the symbol being one of a Quadrature Amplitude Modulation (QAM) constellation; a decision engine coupled to the filter to generate a result indicating one region of a plurality of regions in a QAM constellation diagram, the output of the filter being in the indicated region which includes a plurality of symbols of different radii in the constellation diagram; and an error reduction engine coupled to the decision engine and the filter to reduce a difference between a selected one of a plurality of constants and a modulus of the output; wherein each of the plurality of constants correspond to one of the plurality of regions; wherein the selected one of the plurality of constants is selected according to the result of the decision engine; and wherein the plurality of regions are separate by one or more radii, at least one of the one or more radii is different from any of radii of the QAM constellation.