Patent ID: 7738604

Claim:
A method of discriminating a modulation type comprises: receiving an encoded signal having a plurality of symbols; generating a first and a second cumulative soft metric for each of the plurality of symbols for a predetermined portion of the received encoded signal; comparing the first cumulative soft metric with the second cumulative soft metric to discriminate the modulation type; and upon a favorable comparison of the first cumulative soft metric with the second cumulative soft metric, setting the discriminated modulation type to a first specified modulation type of a plurality of specified modulation types; upon an unfavorable comparison of the first cumulative soft metric with the second cumulative soft metric, setting the discriminated modulation type to a second specified modulation type when the first cumulative soft metric is greater than the second cumulative soft metric; and setting the discriminated modulation type to a third specified modulation type when the first cumulative soft metric is less than the second cumulative soft metric; and decoding, with a decoder, a signal field of the encoded signal based upon the discriminated modulation type.