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Space modulation techniques (SMTs) are multiple-input multiple-output (MIMO) transmitter system implementations that have shown to achieve favorable properties compared to existing MIMO technologies. This includes properties such as lower power consumption, cost, and enhanced error performance. As modern wireless standards have come to demand also more reliability and less latency, in recent work analyzing the reliability of SMTs, it was shown that existing SMT implementations do not effectively perform under degraded system conditions. Essentially, under certain failure conditions, parts of SMT systems become unusable although still effectively operational. As a result, affecting the best achievable spectral efficiency, and thus system data rate of the system. In this work, novel SMT implementations are presented and referred to as hybrid SMTs (HSMTs). HSMTs are designed to degrade in a manner that keeps use of operational hardware and maintains a higher spectral efficiency for longer duration. Four different HSMTs are presented namely; hybrid space shift keying (HSSK), hybrid spatial modulation (HSM), hybrid quadrature space shift keying (HQSSK), and hybrid quadrature spatial modulation (HQSM). Additionally, a reliability analysis framework for HSMTs is presented using two different analytical tools and all introduced models are comparatively studied. [ABSTRACT FROM AUTHOR]

Space modulation techniques (SMTs) have emerged as a family of multiple-input multiple-output (MIMO) transmitter designs that require a maximum of a single RF-chain. SMTs have been analyzed in the context of cost, power, and error performance in past studies and have shown to exert favorable advantages over traditional implementations such as spatial multiplexing (SMX). However, given future application requirements, analysis of the hardware also in the context of reliability becomes essential. In this work, an SMT hardware reliability analysis framework is devised using two quantitative analysis tools consisting of reliability block diagrams (RBDs) and Markov Chains. In addition, a comparative study using commercial component failure rates is performed to analyze how SMTs compare to each other. [ABSTRACT FROM AUTHOR]

Receive space modulation techniques (RSMTs) have recently been introduced as efficient implementations of multiple input multiple output (MIMO) receivers. RSMTs achieve these implementations assuming knowledge of the channel state information (CSI) at the transmitter through a feedback link. RSMTs, however, encounter the limitation that the number of receive antennas has to always be a power of two. In this letter, two new generalized additions to RSMTs are introduced where an arbitrary number of antennas can be deployed. The two techniques are named generalized receive space shift keying (GRSSK) and generalized receive spatial modulation (GRSM). The hardware models for both techniques are defined and compared with each other and to existing models of non-generalized techniques. The bit error rate performance, power consumption, and required hardware cost for practical deployments of both systems are presented and thoroughly discussed. [ABSTRACT FROM AUTHOR]

The RF switch has been highlighted recently as a core component for hardware implementations of the transmitters of space modulation techniques (SMTs). As many other RF components, RF switches have imperfections that can negatively affect the bit error performance of the system. Out of the various imperfections, insertion loss, in particular, is an RF switch property that reflects negatively on the performance of SMTs. Insertion loss in an RF switch causes mismatch between the transmitter and receiver constellation diagrams due to power loss in the transmitted signal. In this letter, the impact of insertion loss is studied analytically and substantiated through Monte Carlo simulation results. It is revealed that insertion loss can significantly impact the system performance if not addressed properly. [ABSTRACT FROM PUBLISHER]

Generalized space modulation techniques (GSMTs), such as generalized space shift keying (GSSK) and generalized spatial modulation (GSM), activate a block of transmit antennas at one time instant to transmit the same data symbol. The aim is to allow the use of arbitrary number of transmit antennas not necessarily power of two. In this paper, novel generalized quadrature space shift keying (GQSSK) and generalized quadrature spatial modulation (GQSM) are presented and analyzed. It has been debated in the literature that these schemes require a number of RF-chains equal to the number of active antennas. In this paper, the design of the transmitters for all GSMTs with optimum number of required RF-chains are discussed and hardware limitations are briefly addressed. A general framework for analyzing the average bit error probability of all these systems is presented and shown to accurately predict the error performance over Rayleigh fading channels. Besides, receiver computational complexity, transmitter power consumption and a rough estimate on the hardware implementation costs for all these schemes are discussed and compared. It is shown that the transmitter implementation of all these schemes requires at most single RF-chain and in some cases no RF-chain is needed. In addition, it is revealed that GQSSK scheme outperforms all other systems and demonstrate the best error performance with low complexity, very low power consumption and modest implementation costs. [ABSTRACT FROM AUTHOR]

Space modulation techniques (SMTs), in which some or all of the data bits modulate a block of spatial constellation symbol, are promising candidates for future 5G wireless systems. They promise data rate enhancements while maintaining low energy consumption, hardware cost, and computational complexity. As such, they attracted significant research interest in the past few years. One of the major assets of SMTs is the assumption that they can operate with a single RF chain at the transmitter even though multiple antennas might be activated at one time instant. Thus far, this claim is anticipated in several research articles but the transmitter designs of the different SMTs with a single RF chain are not addressed yet in the literature. SMTs include different system configurations, such as spatial modulation, space shift keying, quadrature spatial modulation, and quadrature space shift keying. The required hardware components to implement a transmitter for each of these systems with the minimum number of RF-chains are discussed in this paper. In addition, hardware limitations and the impact of different hardware blocks on the overall system performance are discussed. Besides, a comparison among different schemes along with conventional spatial multiplexing algorithm in terms of power consumption, hardware cost, probability of error, and receiver computational complexity is presented. It is shown that some of these techniques can operate without any RF-chain while a single-RF chain is sufficient for other systems. Moreover, these schemes can be traded off in terms of energy savings, complexity, performance, and cost. [ABSTRACT FROM PUBLISHER]