Intelligent reflecting surface (IRS) has recently emerged as a new solution to enhance wireless communication performance via passive signal reflection. In this letter, we unlock the potential of IRS controller in relaying information and propose a novel IRS-assisted communication system with both IRS passive reflection and active relaying. Specifically, we jointly optimize the time allocations for decode-and-forward (DF) relaying by the IRS controller and the IRS passive beamforming to maximize the achievable rate of the proposed system. We also compare the rate performance of the proposed system with the conventional IRS without relaying, and reveal the conditions for one to outperform the other. Simulation results demonstrate that the proposed new design can significantly improve the coverage/rate performance of IRS-assisted systems.

翻译：智能反射表面(IRS)最近成为通过被动信号反射提高无线通信性能的新解决办法。在本信中,我们释放IRS控制器在传递信息方面的潜力,并提议采用IRS被动反射和主动中继两种方式的新型IRS辅助通信系统。具体地说,我们共同优化IRS控制器和IRS被动波束的解码和转发(DF)时间分配,以最大限度地实现拟议系统的可实现率。我们还将拟议系统的费率性能与常规IRS比较,不进行中继,并揭示一种系统优于另一种系统的条件。模拟结果显示,拟议的新设计可以大大改进IRS辅助系统的覆盖范围/速度性能。