论文标题
宽带可重新配置智能表面辅助细胞网络的联合编码框架
A joint precoding framework for wideband reconfigurable intelligent surface-aided cell-free network
论文作者
论文摘要
由于反对细胞间干扰的强大能力，无细胞网络被认为是提高网络容量的有前途的技术。但是，进一步的提高需要高成本和功耗来部署更多的基站（BSS）。为了解决这个问题，灵感来自最近开发的可重构智能表面（RIS）技术，我们提出了RIS辅助网络网络的概念，以通过低成本和功耗来提高容量。关键的想法是用低成本和节能的RIS代替一些所需的BS。然后，在宽带RIS辅助网络中，我们在BSS和RISS中提出了联合预编码设计的问题，以最大程度地提高网络容量。由于法式问题的非凸度和高复杂性，我们开发了一个交替的优化框架来解决这个具有挑战性的问题。特别是，我们通过分数编程将这个问题解散，并解决子问题。请注意，现有作品中考虑的大多数场景都是本文研究的一般场景的特殊情况，并且拟议的联合预编码框架可以作为一般解决方案，以最大程度地利用现有RIS辅助方案的能力。最后，仿真结果表明，与常规的无单元网络相比，可以显着提高所提出方案下的网络容量。
Thanks to the strong ability against the inter-cell interference, cell-free network is considered as a promising technique to improve network capacity. However, further capacity improvement requires to deploy more base stations (BSs) with high cost and power consumption. To address this issue, inspired by the recently developed reconfigurable intelligent surface (RIS) technique, we propose the concept of RIS-aided cell-free network to improve the capacity with low cost and power consumption. The key idea is to replace some of the required BSs by low-cost and energy-efficient RISs. Then, in a wideband RIS-aided cell-free network, we formulate the problem of joint precoding design at BSs and RISs to maximize the network capacity. Due to the non-convexity and high complexity of the formulated problem, we develop an alternating optimization framework to solve this challenging problem. In particular, we decouple this problem via fractional programming, and solve the subproblems alternatively. Note that most of the scenarios considered in existing works are special cases of the general scenario studied in this paper, and the proposed joint precoding framework can serve as a general solution to maximize the capacity in most existing RIS-aided scenarios. Finally, simulation results demonstrate that, compared with the conventional cell-free network, the network capacity under the proposed scheme can be improved significantly.
