Bit Error Probability of Space-Shift Keying MIMO Over Multiple-Access Independent Fading Channels

In this paper, we study the performance of space-shift keying (SSK) modulation for multiple-input-multiple-output (MIMO) wireless systems in the presence of multiple-access interference. More specifically, a synchronous multiuser scenario is considered. The main technical contributions of this paper are given as follows: Two receiver structures based on the maximum-likelihood (ML) criterion of optimality are developed and analytically studied, i.e., single- and multiuser detectors. Accurate frameworks for computing the average bit error probability (ABEP) over independent identically distributed (i.i.d.) Rayleigh fading channels are proposed. Furthermore, simple and easy-to-use lower and upper bounds for performance analysis and system design are introduced. The frameworks account for the near-far effect, which significantly affects the achievable performance in multiple-access environments. In addition, we extend the analysis to generalized SSK (GSSK) modulation, which foresees multiple active antennas at the transmitter. With respect to SSK modulation, GSSK modulation achieves higher data rates at the cost of increased complexity at the transmitter. The performance of SSK and GSSK modulations is compared with that of conventional phase-shift keying (PSK) and quadrature amplitude modulation (QAM) schemes, and it is shown that SSK and GSSK modulations can outperform conventional schemes for various system setups and channel conditions. In particular, the performance gain of SSK and GSSK modulations increases for increasing values of the target bit rate and of the number of antennas at the receiver. Finally, we put forth the concept of coordinated multipoint (or network MIMO) SSK (CoMP-SSK) modulation as a way of exploiting network cooperation and the spatial-constellation diagram to achieve high data rates. Analytical derivations and theoretical findings are substantiated through extensive Monte Carlo simulations for many setups.