Patent ID: 7764741

Claim:
A method of discriminating a modulation type for decoding a signal field of an encoded signal in a wireless communication system, the method comprises: receiving, via a receiver, the encoded signal having a preamble training sequence associated with a frame, the preamble training sequence including the signal field; generating at least a first log-likelihood ratio (LLR) stream and a second LLR stream for each of a plurality of sub-symbols for a predetermined portion of the received encoded signal based upon an m-bit wide modulation reference, wherein m represents the bit width of the modulation reference, the first LLR stream and the second LLR stream includes a plurality of LLR values; summing the plurality of LLR values of the first LLR stream to produce a first cumulative LLR; summing the plurality of LLR values of the second LLR stream to produce a second cumulative LLR; discriminating the first cumulative LLR with the second cumulative LLR to produce a discriminated modulation type output by: comparing the first cumulative LLR with the second cumulative LLR; upon a favorable comparison of the first cumulative LLR with the second cumulative LLR, setting the discriminated modulation type to a first specified modulation type of a plurality of specified modulation types; and upon an unfavorable comparison of the first cumulative LLR with the second cumulative LLR, setting the modulation type to one of a second or a third specified modulation type by: when the first cumulative LLR is greater than the second cumulative LLR, setting the discriminated modulation type to the second specified modulation type; and when the first cumulative LLR is less than the second cumulative LLR, setting the discriminated modulation type to the third specified modulation type; and decoding the signal field of the preamble training sequence based on the discriminated modulation type output.