Abstract

In this paper, we propose high-rate distributed space-time-frequency codes (DSTFCs) to exploit maximum achievable diversity gains over frequency-selective fading channels. The proposed designs achieve full-rate for any number of cooperative nodes, and allow channel variations over multiple OFDM blocks within one DSTFC codeword. We analyze diversity gains of DSTFCs through both conditional and average pairwise error probability (PEP), and we proposes better design criteria based on one-side channel conditional PEP. We show that the difference between the frequency-selective channel orders of source-to-relay and relay-to-destination links may provide extra diversity advantages, thus additional performance gains. Through Monte-Carlo simulations, we demonstrate that proposed high-rate DSTFCs provide notable diversity advantages over existing designs.