Single-carrier frequency domain equalization for broadband cooperative communications
Hakam Mheidat, Murat Uysal, Naofal Al‐Dhahir · 2006
In this paper, we investigate single carrier frequency-domain equalization (SC-FDE) for distributed space-time block codes (D-STBC) in a relay-assisted transmission scenario over frequency-selective fading channels. We assume the special case of a single-relay where the source-to-relay (S rarr R), relay-to-destination (R rarr D), and source-to-destination (S rarr D) links experience possibly different channel delay spreads. Assuming perfect power control between R rarr D and S rarr D links and high signal-to-noise ratio for all underlying links, our performance analysis demonstrates that SC-FDE for D-STBC is able to achieve a maximum diversity order of min(L1, L3)+L2+2 where L1, L2and L3are the channel memory lengths for S rarr R, S rarr D, and R rarr D links, respectively. This illustrates that the smaller of the multipath diversity orders experienced in S rarr R and R rarr D links becomes the performance bottleneck for the relaying path. For the special case of a non-fading relaying path where line-of-sight propagation is possible in either one of these underlying links, we demonstrate that the maximum diversity orders of L1+L2+2 and L3+L2+2 are achievable assuming nonfading R rarr D and S rarr R links, respectively. An extensive Monte Carlo simulation study is presented to corroborate the analytical results and to provide detailed performance comparisons among the competing schemes