Patent ID: 7778341

Claim:
A method of encoding a stream of data elements comprising: splitting the stream of data elements into a first stream and a second stream; encoding the first stream using symbol-based Turbo-encoding to produce a first encoded stream; performing a constellation mapping using a combination of the first encoded stream and a third stream which is based on the second stream; encoding the second stream to produce the third stream using relatively weak encoding compared to that used in encoding the first stream, the method further comprising: defining a signal constellation comprising a plurality of constellation points; defining a plurality of co-sets within the plurality of constellation points such that a minimum distance between constellation points within each co-set is larger than a minimum distance between any constellation points within the signal constellation; performing said constellation mapping by using the first encoded stream to identify a sequence of co-sets of said plurality of co-sets, and by using the third stream to identify a sequence of constellation points within respective co-sets of the sequence of co-sets identified by said first encoded stream.