Trellis demapper for Trellis decoder

摘要

A trellis decoder system (24) uses a feed-forward trellis demapping configuration to prevent error propagation. In a system for processing encoded binary data symbols representable as a symbol constellation, a decoder includes a delay (70) for delaying received encoded symbol data. The decoder also includes a re-encoder (50) for re-encoding decoded symbol representative data and a processor (60) for deriving decoded symbol data. The processor derives decoded symbol data using the delayed encoded symbol data and re-encoded data representative of a difference between successive symbols computed using an error propagation-free, feed-forward configuration. <IMAGE>