| 摘要 |
A technique for converting a sequence of binary digits into a sequence of signalling alphabets of a modulated carrier signal for data transmission. By differentially encoding incoming data, non-linearly encoding the differentially encoded output in a state-dependent sequential manner and mapping the non-linearly encoded output into an expanded set of signalling alphabets having 90, 180 and 270 degree phase ambiguities, enlarged minimum Euclidean distance between possible sequences of signalling alphabets is achieved while the effect of the phase ambiguities of the expanded set of signalling alphabets can be removed in the receiver. This results in a reduced error probability when maximum likelihood decoding and differential decoding are applied in the receiver. |
