Symbol-based soft relaying strategy for cooperative wireless networks

We propose an improved Soft Forwarding (SF) protocol which is based on the symbol-by-symbol detection at the relay node, unlike in the conventional relaying strategy which implements a bit-by-bit signal analysis at the relay node. A relay node which is typically acts like a repeater can avoid unnecessary computation complexity and above all, is resource efficient if compared to the baseline SF. The proposed strategy is implemented based on Maximum Likelihood Detector (MLD) criterion. We simplify the MLD rule to one-dimensional real space such that all metric values are compared in a straight line making the ML performance analysis tractable. Simulations have shown that the proposed schemes outperform the conventional schemes in error rate performance.