Spatially Modulated Orthogonal Space-Time Block Codes with Non-Vanishing Determinants

Abstract

International audienceThis paper proposes a multiple-input multiple-output (MIMO) transmission scheme for M-ary modulations, called Spatially Modulated Orthogonal Space-Time Block Coding (SM-OSTBC), based on the concept of Spatial Constellation (SC) codewords introduced by Le at el. . In the proposed scheme, transmit codeword matrices are generated by multiplying SC matrices with codewords constructed from Orthogonal Space-time Block Codes (O-STBC). The maximum spectral efficiency of the proposed scheme is equal to (n_T-2+ log_2 M) bpcu, where n_T is the number of transmit antennas and M is the modulation order. The SC matrices provide a means of carrying information bits together with the O-STBC codewords and allow the SM-OSTBC scheme to achieve second-order transmit diversity by satisfying the non-vanishing determinant property. A systematic method to design the SC codewords for an even number of transmit antennas greater than 3 is presented. A single-stream maximum-likelihood (ML) decoder, which requires a low computational complexity thanks to the structure of the SM-OSTBC codewords and to the orthogonality of the O-STBCs, and a sphere decoder with further reduced signal processing complexity are developed. The bit error rate (BER) performance of the proposed scheme is studied by using both theoretical union bound analysis and computer simulations. Finally, simulation results are presented in order to compare BER performance, energy efficiency and decoding complexity of the proposed scheme with those of several existing MIMO transmission schemes

An adaptive transmission protocol for exploiting diversity and multiplexing gains in wireless relaying networks

“…In general, such combinations are achieved using MIMO systems. This allows the construction of a fixed STBC-SM code as the number of antennas at the transmitter is fixed [32][33][34][35][36]. These designs are also bounded by a transmit diversity gain of 2.…”

“…Unlike [32][33][34][35][36], this protocol offers a transmit diversity gain of N 0 (N ≤ N 0 ≤ 1) because the possibility of activating N 0 number of relays simultaneously during transmission. Given some control information, the protocol can be adapted to transmit through any given number of relays (N 0 ).…”

“…Recently, the design of STBC-SM codes has drawn attention because of the promising improvements shown [32][33][34][35][36]. In this section, background and some required definitions of STBC-SM that are needed to work for D-STBC-SM are shown.…”

“…The phase rotation θ i is set to avoid rank deficiency among codebooks to mitigate diversity gain loss. The designs of a more complex STBC-SM in a MIMO system have shown promising improvements and recently have started to attract attention [32][33][34][35][36].…”

Single-RF and Twin-RF Spatial Modulation for an Arbitrary Number of Transmit Antennas

“…Additionally, improved variants of multiple-RF aided SM were developed in [21]- [35] to further investigate the multiplexing [21]- [29] and diversity gains [30]- [35] of SM systems. For the multiplexing based SM schemes, the beam-forming based generalized SM scheme of [21] and the time-variant number of activated TAs based SM scheme of [28] employed N t RF chains at the transmitter.…”