Spectral Efficient Spatial Modulation Techniques

Abstract

Space modulation techniques (SMTs) have emerged as promising candidates for spectral-and energy-efficient wireless communication systems since they strike a good balance among error performance, power efficiency, spectrum efficiency, and receiver complexity. In SMTs, the information is not only conveyed by the habitual M-ary signal constellations; rather, it is also conveyed by the indices of the transmit antennas. As such, the indices of the transmit antennas are harnessed in such a manner that they enhance the transmission efficiency compared with the other multiple-input multiple-output opponents. Despite their exceptional advantages, SMTs suffer from a major drawback, which lies in the logarithmic proportion between their achievable data rates and the number of transmit antennas. In this regard, the fully generalized spatial modulation (F-GSM) and the fully quadrature spatial modulation (F-QSM) are proposed in this paper in order to vanquish this controversial drawback. In F-GSM and F-QSM, the transmit antennas used for data transmission are varied from the state in which only one transmit antenna is activated to the state in which multiple/all transmit antennas are activated. Therefore, a linear relationship between the achievable data rates and the number of transmit antennas is acquired. Moreover, a novel mathematical framework for assessing the average bit error rate performance of different SMTs is delineated. The driven mathematical framework is considered as the first major attempt to generalize the analytical analysis of different SMTs. In addition, the receiver's computational complexity of the proposed schemes is obtained and analyzed in terms of the computational complexity of different SMTs. The simulation results substantiate the validity of the analytical analysis conducted throughout the paper, as they are very akin to the obtained analytical formulas.

Enhanced redesigned spatial modulation: Design and performance evaluation under correlated fading channels

“…Enhanced spatial modulation (ESM) is introduced, which activates either single or double antenna combination at a time instant . When a single antenna is active, a symbol from higher order modulation scheme is transmitted and when two antennas are active, a symbol from lower order modulation scheme is transmitted from the active antennas.…”

“…22 Enhanced spatial modulation (ESM) is introduced, which activates either single or double antenna combination at a time instant. 23 When a single antenna is active, a symbol from higher order modulation scheme is transmitted and when two antennas are active, a symbol from lower order modulation scheme is transmitted from the active antennas. The modulation order of the lower order modulation scheme is selected as half the order of higher order modulation scheme such that constant spectral efficiency is maintained at every time instant.…”

Pilot-Based Adaptive Channel Estimation for Underwater Spatial Modulation Technologies

“…Therefore, SM has less receiver complexity, it effectively removes ICI, and it does not require IAS of the MIMO link due to availability of one RF chain at the transmitter. Different SMTs are introduced [10,[15][16][17][18][19][20][21][22][23] by allowing it to enable one or more RF chains using different techniques so that high throughput and enhanced SNR can be achieved. GSM [21,22] is the most prevalent technique, in which the multiple antennas are active in each communication channel so that high data rate can be achieved.…”

“…FGSM has been proposed in [15,16] where the antenna subsets are varying between the activation of a single antenna and the activation of multiple/all antennas. These variations in the number of activated transmission antennas enhance the realization of the communication channel, resulting in increased available data rate.…”

Fast Scalable Architecture of a Near-ML Detector for a MIMO-QSM Receiver

“…Quadrature spatial modulation (QSM) is an SM based transmission technique that uses the quadrature (Q) and the in-phase (I) QAM components to independently modulate a spatial constellation. As a result, QSM has better spectral efficiency (SE) since it transmits twice the number of bits in the spatial domain [9][10][11] with the aim of further improving the performance of SM systems in terms of bit error rate.…”