A new two-user cooperative transmission scheme with low-complexity FDE in DFDMA systems

Conventional distributed Alamouti-like space-time block codes (STBC) transmission strategy in two-user cluster-based cooperative communication systems (Sushanta and Monisha, 2008) is extended to single-carrier frequency-domain equalization (SC-FDE) systems, and a two-user cooperative transmission scheme in distributed frequency division multiple access (DFDMA) systems is proposed for uplink wireless transmission. The two users in the proposed scheme are allocated different subcarriers, and complete one cooperative process in two time slots, whereas the conventional scheme needs four time slots. At the destination, a lower-complexity single-carrier zero-forcing frequency-domain equalization (FDE) and a simpler diversity combining can be applied in the proposed scheme. Monte-Carlo simulation results verify that the proposed scheme could achieve order-two cooperative diversity gain and performance gain by 3 dB than the conventional scheme with the same spectral efficiency.