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In this paper, we consider a spatial modulation (SM)-based multiple-input–single-output (MISO) system relying on a single radio-frequency chain equipped with a finite-rate feedback channel to provide quantized channel state information (CSI) to the transmitter. First, under the assumption of Rayleigh flat-fading channels and perfect CSI at the transmitter (CSIT), we analyze the symbol error probability (SEP) of an SM scheme, which perfectly compensates the channel phase and employs constellation rotation at the different transmit antennas (TAs). Then, we consider a more practical scenario, where scalar quantization of the channel phase angles is employed, and the quantized CSI is made available to the transmitter via a finite-rate feedback channel. We analyze the SEP reduction, i.e., Pe_L, relative to perfect CSIT, imposed by the quantized CSIT (Q-CSIT). We show that at a high feedback rate, Pe_L varies as C^\prime\mbox2^-2B, where each channel phase angle is quantized to B bits, and C^{\prime} is a constant. Furthermore, based on the rotational symmetry of the M-ary phase-shift keying ( M-PSK) signal constellation, we propose a novel feedback scheme, which requires (n_t-\mbox{1})\log_2(M) fewer bits of feedback with any performance erosion, where n_t$ is the number of TAs. We characterize the performance of the SM-MISO system with finite-rate feedback and validate our analysis through Monte Carlo simulations. [ABSTRACT FROM AUTHOR]

In this paper, we present novel precoding methods for multiuser Rayleigh fading multiple-input–multiple-output (MIMO) systems when channel state information (CSI) is available at the transmitter (CSIT) but not at the receiver (CSIR). Such a scenario is relevant, for example, in time-division duplex (TDD) MIMO communications, where, due to channel reciprocity, CSIT can be directly acquired by sending a training sequence from the receiver to the transmitter(s). We propose three transmit precoding schemes that convert the fading MIMO channel into a fixed-gain additive white Gaussian noise (AWGN) channel while satisfying an average power constraint. We also extend one of the precoding schemes to the multiuser Rayleigh fading multiple-access channel (MAC), broadcast channel (BC), and interference channel (IC). The proposed schemes convert the fading MIMO channel into fixed-gain parallel AWGN channels in all three cases. Hence, they achieve an infinite diversity order, which is in sharp contrast to schemes based on perfect CSIR and no CSIT, which, at best, achieve a finite diversity order. Further, we show that a polynomial diversity order is retained, even in the presence of channel estimation errors at the transmitter. Monte Carlo simulations illustrate the bit error rate (BER) performance obtainable from the proposed precoding scheme compared with existing transmit precoding schemes. [ABSTRACT FROM PUBLISHER]