Distributed turbocoder for block-fading channels

A cooperative communications system comprising a source terminal (s), at least one relay terminal (r), and a destination terminal (d), the source terminal being adapted to transmit information data (I) to the destination terminal over a first multi-carrier transmission channel, said system comprising a distributed turbocoder over said source terminal and at least said relay terminal, the part of the turbocoder residing on the source terminal, referred to as first part (510, 710, 810), comprising a first systematic path and at least one first convolutive coding path (CCs) coding said information data to generate first parity data (Ps), the relay terminal estimating said information data from a signal received from the source terminal, the part of the turbocoder residing on the relay terminal, referred to as second part (520, 720, 820), comprising a second systematic path providing the information data thus estimated (Îr) and a second convolutive coding path (CCr) coding the latter after having interleaved them to generate second parity data (Pr), said estimated data (Îr) and said second parity data (Pr) being transmitted over a second multi-carrier transmission channel, characterised in that said system comprises at least one frequency scheduler (FSs,FSr) residing on the source terminal or the relay terminal, said scheduler allocating the carriers (Ωhigh) exhibiting deep fading to the data originating respectively from the first or the second systematic path and the carriers exhibiting weak fading (Ωlow) to the data originating respectively from the first or the second convolutive coding path.