Abstract
The present disclosure provides a cooperative multimedia communication systems and a communication method. The source node includes a first hierarchical modulation constellation mapping, and modulates two data streams (the base stream and the refinement stream, which have different protection levels), and transmits a first signal and a second signal. The relay node includes a protection-level-exchanging modulation and a second hierarchical modulation constellation mapping, and modulates the second signal to generate a third signal, and transmits the third signal. The destination node receives the first signal and the third signal, and performs optimal data detection. The present disclosure designs a pair of optimal hierarchical constellation mappings respectively for the source node and the relay node.