VLSI Implementation of Optimal Detection for Spatial Modulation

Spatial Modulation (SM) has been recently proposed as an efficient transmission technology for Multiple-Input-Multiple-Output (MIMO) wireless communication systems, which can provide increased spectral efficiency comparing to that of conventional singleantenna systems with reduced hardware complexity. These features are attained by employing the socalled 3D constellation diagram, namely a modulation and coding scheme which i) activates, at each time instance, a single transmit antenna that transmits a given data symbol from a conventional signal constellation, e.g. M-PSK or M-QAM and ii) exploits the spatial position of the active antenna as a third dimension for data transmission. The antenna index used for information transmission constitutes the so-called spatial constellation. This paper proposes an ASIC implementation of the Maximum Likelihood (ML) optimum decoder. The complexity of this decoder is significantly lower than that of well known schemes, such as the vertical Bell Labs space time (V-BLAST) decoder. The architecture of the proposed implementation is discussed in detail and its performance in terms of the achieved bit error probability is assessed.