Performance analysis of reconfigurable intelligent surface-assisted spatial modulation over different fading channels

With the developing technology day by day, the number of users of wireless communication devices is increasing and much faster data transmission is needed. However, traditional radio-frequency communication methods are insufficient to meet the goals of new generation wireless communication technologies such as ultra-fast data transfer and high bandwidth. The inability of currently used communication techniques to provide the required spectral efficiency has made it necessary to design new transmitter-receiver structures and to develop innovative modulation techniques. In this thesis study; Spatial modulation (SM) techniques, which are proposed to eliminate problems such as inter-channel interference and receiver complexity in wireless communication systems, and adaptive intelligent surface (RIS) technology, which is proposed to reduce the performance degradation in data transmission caused by multi-path fading wireless environments. RIS-assisted SM (RIS-SM) schemes put forward by combining them are discussed on different multipath fading channels such as Rayleighi Ricean and κ-μ. By utilizing the ability of RISs to effectively control and change the wireless channel, error performance analysis on different wireless channels was performed in terms of bit error rate (BER). The highest likelihood (maximum likelihood, ML) detection method was used in the analysis of all the systems considered. The error performance results obtained are presented with computer simulations. In substance, the aim of this thesis is to achieve high data transmission rates by providing data transmission with RIS-SM techniques in wireless communication systems, to solve the synchronization problem between antennas, to provide a more reliable transmission environment, to increase the channel capacity and to reach the blind spot through RIS. It is to increase the transmission medium capacity by providing a direct line of sight between the antennas.