摘要 |
To demodulate a quadrature amplitude modulation (QAM) signal, a reception point is determined corresponding to a symbol in the QAM signal that is received where the symbol is mapped to one reference point of a plurality of reference points in a rotated constellation and the plurality of reference points are represented by an in-phase (I) coordinate and a quadrature-phase (Q) coordinate. A plurality of candidate points corresponding to a portion of the plurality of reference points are selected based on distances between the reception point and the respective reference points. The reception point is demapped by calculating a plurality of log-likelihood ratios based on the plurality of candidate points, the plurality of log-likelihood ratios corresponding to bits of data represented by the reception point.
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