Reconfigurable Intelligent Surface-Assisted Spatial Scattering Modulation

Reconfigurable intelligent surface (RIS) and spatial scattering modulation (SSM) are promising candidates for future generations of wireless communication. The former provides an enhanced transmission environment by providing an alternative communication path, while the latter boosts spectral efficiency. In this letter, we firstly propose a novel uplink millimeter-wave (mmWave) communication system that utilizes both RIS and SSM to support data transmission over wireless channels. Specifically, we design the reflecting phase shifters at the RIS to support the two-hop communications. Moreover, a maximum likelihood detector is adopted to a new system with RIS-SSM and a new analytical expression for a tight union upper bound on the bit error rate (BER) is derived. Monte Carlo simulation results are provided to verify the accuracy of the derived analytical expression. Numerical results reveal that the proposed RIS-SSM scheme has a significantly lower BER than the traditional SSM.