Among the recent advances and innovations in wireless technologies, reconfigurable intelligent surfaces (RISs) have received much attention and are envisioned to be one of the enabling technologies for beyond 5G (B5G) networks. On the other hand, active (or classical) cooperative relays have played a key role in providing reliable and power-efficient communications in previous wireless generations. In this article, we focus on hybrid network architectures that amalgamate both active relays and RISs. The operation concept and protocols of each technology are first discussed. Subsequently, we present multiple use cases of cooperative hybrid networks where both active relays and RISs can coexist harmoniously for enhanced rate performance. Furthermore, a case study is provided which demonstrates the achievable rate performance of a communication network assisted by either an active relay, an RIS, or both, and with different relaying protocols. Finally, we provide the reader with the challenges and key research directions in this area.

翻译：在最近无线技术的进步和创新中,可调整的智能表面(RIS)受到很大关注,被认为是5G(B5G)网络之外的一种赋能技术,另一方面,积极(或古典)合作式继电器在前几代无线通信提供可靠和节能通信方面发挥了关键作用。在本条中,我们侧重于混合网络结构,将主动中继器和RIS结合起来。首先讨论每种技术的操作概念和协议。随后,我们介绍了合作性混合网络的多种使用案例,积极中继器和RIS可以和谐地共存,提高费率性能。此外,我们提供了案例研究,展示了通信网络的可实现速度性能,这些通信网络得到主动中继器、RIS或两者的协助,并且有不同的转发程序。最后,我们向读者介绍该领域的挑战和关键研究方向。