A static protocol to achieve optimal diversity-multiplexing tradeoff for high diversity gains in half-duplex relay channels

In this paper, we study the Diversity-Multiplexing Tradeoff (DMT) of a novel Decode or Quantize and Forward (DoQF) protocol for the half duplex single relay channel. It is well-known that the so-called Dynamic Decode and Forward (DDF) achieves the Multiple-Input-Single-Output (MISO) bound in the range of multiplexing gains r < 0.5. But to the best of our knowledge, no practical coding scheme allows the implementation of the DDF, so that it essentially remains a theoretical protocol. On the opposite, the proposed DoQF protocol is based on a practical static coding-decoding strategy. Our results show that the DoQF achieves the MISO bound in the range of multiplexing gains r < 0.25 (and still has an attractive performance for r < 0.37). To the best of our knowledge, this makes the DoQF the only static protocol that achieves the MISO upperbound without any feedback link between nodes.