TY - JOUR
T1 - Equalization techniques for distributed space-time block codes with amplify-and-forward relaying
AU - Mheidat, Hakam
AU - Uysal, Murat
AU - Al-Dhahir, Naofal
N1 - Funding Information:
Manuscript received August 2, 2005; revised April 25, 2006. The work of M. Uysal was supported in part by an NSERC Special Opportunity (Grant SROPJ305821-05). The work of N. Al-Dhahir was supported in part by the Texas Advanced Technology (ATP) program under Contract 009741-0023-2003 and by NSF Contracts CCF 0430654 and DMS 0528010. The associate editor coordinating the review of this paper and approving it for publication was Dr. Michael Buehrer.
PY - 2007/5
Y1 - 2007/5
N2 - In this paper, we investigate equalization methods for cooperative diversity schemes over frequency-selective fading channels. Specifically, we consider three equalization schemes proposed originally for conventional space-time block codes (STBC) [1]-[3] and extend them to distributed STBC in a cooperative transmission scenario with amplify-and-forward relaying. The distributed STBC equalization schemes are named after their original counterparts as distributed time-reversal (D-TR) STBC, distributed single-carrier (D-SC) STBC, and distributed orthogonal frequency division multiplexed (D-OFDM) STBC. The underlying orthogonality of distributed STBC results in decoupled data streams at the receiver side allowing low-complexity implementations. Without loss of generality, we consider a single-relay scenario where the source-to-relay S → R, relay-to-destination R → D, and source-to-destination S → D links experience possibly different channel delay spreads. Under the assumption of perfect power control for the relay terminal and high signal-to-noise ratio (SNR) for the underlying links, our performance analysis demonstrates that D-TR-STBC, D-SC-STBC, and coded D-OFDM-STBC schemes are able to achieve a maximum diversity order of min(L1, L3+ L2 + 2 where L1, L2, and L3 are the channel memory lengths for S → R, S → D, and R → D→ links, respectively. This illustrates that the minimum of the multipath diversity orders experienced in S → R and R → D links becomes the performance bottleneck for the relaying path. For the case of a nonfading relaying path where line-of-sight propagation is possible in either one of these underlying links, we demonstrate that diversity orders of L1+L2+2 and L3+L2 +2 are achievable assuming nonfading S → R and R → D links, respectively. An extensive Monte Carlo simulation study is presented to corroborate the analytical results and to provide detailed performance comparisons among the three candidate equalization schemes.
AB - In this paper, we investigate equalization methods for cooperative diversity schemes over frequency-selective fading channels. Specifically, we consider three equalization schemes proposed originally for conventional space-time block codes (STBC) [1]-[3] and extend them to distributed STBC in a cooperative transmission scenario with amplify-and-forward relaying. The distributed STBC equalization schemes are named after their original counterparts as distributed time-reversal (D-TR) STBC, distributed single-carrier (D-SC) STBC, and distributed orthogonal frequency division multiplexed (D-OFDM) STBC. The underlying orthogonality of distributed STBC results in decoupled data streams at the receiver side allowing low-complexity implementations. Without loss of generality, we consider a single-relay scenario where the source-to-relay S → R, relay-to-destination R → D, and source-to-destination S → D links experience possibly different channel delay spreads. Under the assumption of perfect power control for the relay terminal and high signal-to-noise ratio (SNR) for the underlying links, our performance analysis demonstrates that D-TR-STBC, D-SC-STBC, and coded D-OFDM-STBC schemes are able to achieve a maximum diversity order of min(L1, L3+ L2 + 2 where L1, L2, and L3 are the channel memory lengths for S → R, S → D, and R → D→ links, respectively. This illustrates that the minimum of the multipath diversity orders experienced in S → R and R → D links becomes the performance bottleneck for the relaying path. For the case of a nonfading relaying path where line-of-sight propagation is possible in either one of these underlying links, we demonstrate that diversity orders of L1+L2+2 and L3+L2 +2 are achievable assuming nonfading S → R and R → D links, respectively. An extensive Monte Carlo simulation study is presented to corroborate the analytical results and to provide detailed performance comparisons among the three candidate equalization schemes.
KW - Cooperative diversity
KW - Distributed space-time block coding (STBC)
KW - Equalization
KW - Fading channels
KW - Pairwise error probability
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U2 - 10.1109/TSP.2006.889974
DO - 10.1109/TSP.2006.889974
M3 - Article
AN - SCOPUS:34247884292
SN - 1053-587X
VL - 55
SP - 1839
EP - 1852
JO - IEEE Transactions on Signal Processing
JF - IEEE Transactions on Signal Processing
IS - 5 I
ER -