Performance of SSK-based Receive Diversity RIS-assisted System with Nakagami-m Fading Channels

Over recent years, reflective intelligent surface (RIS) and index modulation (IM) technologies have proven to be potential technologies for improving the performance of the fifth generation (5G) and beyond 5G wireless communication systems. In this paper, a space-shift keying (SSK) (an IM scheme)-based receive diversity and Nakagami-m faded wireless system is considered, which utilizes a RIS system in between the transmitter and the receiver. A greedy detector is proposed for the system, which chooses a target receiver antenna based on the maximum received energy at the diversity branches. An analytical framework is proposed based on a characteristic function approach to obtain a closed-form expression of the probability of erroneous detection of the target antenna. Asymptotic expressions at high and low average signal-to-noise ratios lead to the observation of a performance saturation, attributed to the structure of the greedy detector. Furthermore, numerical results are presented to show the dependency of the system’s performance on the various system parameters.