Patent ID: 8000402

Claim:
A method for performing, in a processor, quadrature amplitude modulation (QAM) decoding for a plurality of received input tones in parallel, comprising: (a) reading a constellation size for each of the plurality of input tones; (b) reading input data for each of the plurality of input tones, wherein the input data includes an x-coordinate value and a y-coordinate value; (c) for each of the plurality of input tones, determining, in parallel, an ideal point in a QAM constellation of the associated constellation size closest to a point having the x-coordinate value and y-coordinate value for the input tone, wherein step (c) is performed in a first manner for each of the plurality of input tones that have a constellation size that is an even value and in a second manner for each of the plurality of input tones that have a constellation size that is an odd value that is greater than or equal to five; and (d) storing a data value associated with the determined ideal point for each of the plurality of input tones in a destination register.