摘要 |
<p>Soft bit values are generated for received symbols transmitted based on a modulation constellation by demodulating the received symbols via a sequence of demodulation stages, each demodulation stage producing a symbol decision based on an effective constellation. Each effective constellation used by a non-final one of the demodulation stages includes subsets of centroids approximating a region of the modulation constellation. Adjacent ones of the subsets have one or more common points so that at least two adjacent subsets overlap. The soft bit values for the symbol decisions are determined based on detection metrics computed during demodulation for the points included in the effective constellation constructed incrementally over the sequence of demodulation stages, the effective constellation produced by the final demodulation stage being devoid of one or more points included in the modulation constellation.</p> |