Research On Techniques Of MIMO Based On Layered Space Shift Keying Modulation

The multiple-input multiple-output(MIMO) technologies have improved the system capacity greatly, for it use multiple antennas in wireless communication. Therefore it has become one of the key technologies of future wireless communication systems. Since space shift keying modulation(SSK) technique activates only one antenna each time, it becomes one of the key technologies of the future wireless communication techniques, providing benefits such as no inter-channel interference, no inter-antenna synchronization and reduction of radio frequency(RF) chains compared with conventional MIMO systems.In this paper, we have surveyed the existing space shift keying and Spatial Modulation techniques. We present a layered space shift keying(LSSK) modulation scheme based on the conventional space shift keying techniques to fully exploit the spatial domain to transmit information bits. Furthermore, we have proposed a layered-and-joint(LJ) near-optimal detection algorithm based on the layered architecture of LSSK to reduce the detection complexity and a precoding scheme in LSSK system,which is called the layered channel information preservation(LCIP) method. In the end, we present a high rate transmit-diversity-assisted space shift keying modulation to achieve the transmit diversity gain over SSK system with high spectrum efficiency.The first chapter elaborates traditional space shift keying modulation and spatial modulation algorithms. Another several highlight existing relevant modulation technique was present in this charpter and was compared with the proposed scheme later. At the end of the first chapter, the contribution of our research and the logical structure of the paper were described.The second chapter introduced the system model of LSSK firstly, then the modulation and demodulation scheme of LSSK system. This chapter also presents the analysis of optimal detection for LSSK system. This chapter have derived the tight upper bound of bit error rate performance of LSSK system and the loose upper bound. At the end of this chapter, we present the comparison between the conventional SSK schemes and the proposed LSSK scheme.In chapter 3, we propose a layered-and-joint(LJ) near-optimal detection algorithm based on the layered architecture of LSSK to reduce the detection complexity. In LJ detection, layered detection is performed to find a set of detection candidates for each layer and then joint detection is performed with these candidates. We show that the performance of LJ detection is quite close to that of optimal maximum likelihood(ML) detection with a significantly reduced detection complexity for high spectrum efficiency scenarios.In chapter 4, a multi-user precoding scheme in LSSK system was studied in this chapter. The interference between layers in LSSK system is mitigated by precoding at the transmitter and the complexity of the receiver is significantly reduced. This chapter describes the detail process of generating the pre-coding signals for the proposed layered channel information preservation(LCIP) precoding method and its bit error rate performance analysis is also presented. We show the simulation results of the comparison between the proposed precoding scheme and ZF precoding for BER performance.The fifth chapter, we propose a novel high rate transmit diversity assisted space shift keying(HT-SSK) modulation scheme to achieve the transmit diversity and give two examples of transmit alphabets. The proposed HT-SSK modulation scheme achieves higher spectrum efficiency while it provides significant transmit diversity gain. Simulation results show that it also outperforms the conventional spatial modulation(SM) scheme.Conclusions of the work in the thesis are given in Chapter 6, and the future research direction about the space shift keying modulation or spatial modulation techniques in the future wireless communication systems is discussed.