Robust STBC scheme for IRS-assisted SWIPT systems

Abstract Herein, we propose a block-wise design scheme that involves combining a space--time block code (STBC) with an intelligent reflecting surface (IRS)-assisted synchronous wireless information and power transfer (STBC-BIRS-SWIPT) scheme. The proposed scheme increases the spectral efficiency and diversity of wireless communication systems while allowing synchronous energy and information transmission. By leveraging generalized spatial modulation, additional bits of information can be transmitted via the IRS. In particular, the IRS is divided into distinct blocks, each with unique group selection patterns that exhibit a specific mapping relation with information bits. The IRS has components that reflect source signals to information decoding and energy harvesting receivers. We established a lower bound for the mean symbol error rate (SER) and calculated the bit error rate using maximum-likelihood detection. The simulation results demonstrate the superior performance of the STBC-BIRS-SWIPT scheme over traditional power-splitting schemes and confirm the closeness of the SER lower bound to the exact SER.