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Successive relaying has recently emerged as an effective technique for cooperative networks and provides significant improvements in bandwidth efficiency over traditional relaying techniques; however, to achieve full-diversity, the available successive relaying protocols generally assume noise-free source-relay and interference-free inter-relay channels. In this paper, a novel successive relaying protocol is proposed for N-relay wireless networks by removing these optimistic assumptions. The proposed protocol benefits from distributed space-time block codes (STBCs) with coordinate interleaving and relay selection. It achieves a diversity order of two and high transmission rate under realistic network conditions with single-symbol maximum likelihood (ML) detection. A general N-relay signaling protocol is presented, and specific design examples are given for N=2, 3 and 4-relay cooperative networks. The average symbol error probability (ASEP) is analytically derived and shown to match with computer simulation results. It is also shown via computer simulations that the proposed scheme achieves significantly better error performance and is more robust to channel estimation errors than its counterparts given in the literature under realistic network conditions. [ABSTRACT FROM AUTHOR]

Spatial modulation (SM), in which multiple antennas are used to convey information besides the conventional M-ary signal constellations, is a new multiple-input multiple-output (MIMO) transmission technique, which has recently been proposed as an alternative to V-BLAST (vertical Bell Labs layered space-time). In this paper, a novel MIMO transmission scheme, called spatial modulation with trellis coding (SM-TC), is proposed. Similar to the conventional trellis coded modulation (TCM), in this scheme, a trellis encoder and an SM mapper are jointly designed to take advantage of the benefits of both. A soft decision Viterbi decoder, which is fed with the soft information supplied by the optimal SM decoder, is used at the receiver. A pairwise error probability (PEP) upper bound is derived for the SM-TC scheme in uncorrelated quasi-static Rayleigh fading channels. From the PEP upper bound, code design criteria are given and then used to obtain new 4-, 8- and 16-state SM-TC schemes using quadrature phase-shift keying (QPSK) and 8-ary phase-shift keying (8-PSK) modulations for 2,3 and 4 bits/s/Hz spectral efficiencies. It is shown via computer simulations and also supported by a theoretical error performance analysis that the proposed SM-TC schemes achieve significantly better error performance than the classical space-time trellis codes and coded V-BLAST systems at the same spectral efficiency, yet with reduced decoding complexity. [ABSTRACT FROM PUBLISHER]