Performance Analysis of RIS-Aided Space Shift Keying With Channel Estimation Errors

TL;DR

This paper analyzes the performance of RIS-assisted space shift keying systems under channel estimation errors, deriving closed-form and asymptotic error probability expressions validated by simulations.

Contribution

It provides the first analytical expressions for RIS-SSK performance considering imperfect CSI, including closed-form and asymptotic error probabilities.

Findings

Derived closed-form pairwise error probability expressions.

Obtained asymptotic average bit error probability expressions.

Validated analytical results with Monte Carlo simulations.

Abstract

In this paper, we investigate the reconfigurable intelligent surface (RIS) assisted space shift keying (SSK) downlink communication systems under the imperfect channel state information (CSI), where the channel between the base station to RIS follows the Rayleigh fading, while the channel between the RIS to user equipment obeys the Rician fading. Based on the maximum likelihood detector, the conditional pairwise error probability of the composite channel is derived. Then, the probability density function for a non-central chi-square distribution with one degree of freedom is derived. Based on this, the closed-form analytical expression of the RIS-SSK scheme with imperfect CSI is derived. To gain more valuable insights, the asymptotic ABEP expression is also given. Finally, we validate the derived closed-form and asymptotic expressions by Monte Carlo simulations.