Performance of RIS-Aided OFDM-IM under κ-μ Fading Channels and Transceiver Hardware Impairments

Abstract

While index modulation (IM) techniques are currently popular and have achieved a breakthrough in data transmission, orthogonal frequency division multiplexing systems (OFDM) are also prominent. The studies on controlling reflection continue with the characteristics of electromagnetic waves. Also, to enhance the service quality or boost the speed of wireless communication access, IM techniques are becoming widespread in the literature. In this context, reconfigurable intelligent surfaces (RISs), which are composed of numerous lowcost passive elements, are used to enhance the performance of OFDM-IM systems. However, many existing studies on RIS-based communication scenarios consider perfect hardware and static channel assumptions, which are generally not encountered in practical communication applications. Next-generation technologies require unusually high carrier frequencies prone to hardware impairments (HWIs). This article introduces a detailed analytical performance evaluation of RIS-aided OFDM-IM systems with transceiver HWIs. Because the fitting of kappa-& micro; fading distribution to real-world scenarios is more suitable than that accomplished by the traditional distributions, kappa-& micro; channel model is employed in this work. The average bit error rate (ABER) under the impact of HWIs is analyzed by calculating the expression terms of the outage probability (OP) and the average pairwise error probability (APEP). Simulations revealed that integrating an RIS design into the OFDM-IM system improves the overall ABER performance compared to the classical OFDM-IM communication approach by reducing the effects of transceiver HWIs in kappa-& micro; fading environments.