Reconfigurable intelligent surface (RIS) has recently emerged as a promising technology enabling next-generation wireless networks. In this paper, we develop an improved index modulation (IM) scheme by utilizing RIS to convey information. Specifically, we study an RIS-aided multiple-input single-output (MISO) system, in which the information bits are conveyed by reflection patterns of RIS rather than the conventional amplitude-phase constellation. Furthermore, the K-means algorithm is employed to optimize the reflection constellation to improve the error performance. Also, we propose a generalized Gray coding method for mapping information bits to an appropriate reflection constellation and analytically evaluate the error performance of the proposed scheme by deriving a closed-form expression of the average bit error rate (BER). Finally, numerical results verify the accuracy of our theoretical analysis as well as the substantially improved BER performance of the proposed RIS-based IM scheme.
翻译:可重新配置的智能表面(RIS)最近作为一种有希望的技术出现了,有利于下一代无线网络。在本文中,我们通过利用RIS传递信息开发了一个改进的指数调制(IM)方案。具体地说,我们研究一个RIS辅助的多投入单输出(MISO)系统,在这个系统中,信息比特是通过RIS的反射模式而不是传统的振幅级星座传递的。此外,K手段算法被用来优化反射星座,以改善错误性能。此外,我们提出一种通用的灰色编码方法,用于绘制信息比特,以适当的反射星座和分析评价拟议方案错误性能,方法是得出平均位误差率(BER)的封闭式表达方式。最后,数字结果验证了我们理论分析的准确性以及拟议的基于RIS的IMM计划大幅改进的BER性能。