Performance Analysis of Reconfigurable Intelligent Surface Assisted STBC and DSTBC Systems

The reconfigurable intelligent surface (RIS) technology has generated considerable interest due to its advantages of low cost, easy deployment, and high controllability. In this article, a RIS-assisted space-time block code (STBC) scheme and a RIS-assisted differential space-time block code (DSTBC) scheme with a single radio frequency signal generator at the transmitter side are proposed to reduce the hardware overhead of classical STBC and the channel state information (CSI) acquisition at the receiver side. RIS is utilized to enhance symbol error probability (SEP) performance and reduce the number of antennas of the classical STBC and DSTBC schemes. After that, we analyze the SER performance of the two schemes, emphasizing the diversity gain, and find that increasing only the number of divided parts of RIS for the two schemes could enhance the diversity gain without adding extra hardware. Monte Carlo simulations are provided to show the effectiveness of our proposed schemes and it has been shown that the two proposed schemes outperform the reference schemes in terms of SER performance.