论文标题
Multicell IRS辅助系统的联合波束形成和相移优化
Joint Beamforming and Phase Shift Optimization for Multicell IRS-aided OFDMA-URLLC Systems
论文作者
论文摘要
本文研究了用于智能反射表面(IRS)的资源分配算法设计(IRS)帮助多输入单输出(MISO)正交频分部多访问多访问(OFDMA)多切尔网络,其中一组基本站配合使用以服务一组超级可靠的低建筑通信(URLLC)。通过为具有不利传播条件的URLLC用户创建虚拟的视觉线来,将部署IRS来增强通信渠道并提高可靠性。这是关于IRS增强ofdma-urllc系统的第一项研究。资源分配算法设计是作为优化问题提出的,以最大化加权系统总和吞吐量,同时保证URLLC用户的服务质量。优化问题是非凸,发现全球最佳解决方案需要高度计算复杂性,这对于实时应用而言是不可取的。因此,提出了一种次优的迭代算法,该算法使用新的迭代秩最小化方法来优化每种迭代中的所有优化变量。保证该算法会收敛到公式优化问题的局部最佳解决方案。我们的仿真结果表明,与两个基线方案相比,提出的IRS设计有助于URLLC并产生较大的性能增长。
This paper investigates the resource allocation algorithm design for intelligent reflecting surface (IRS) aided multiple-input single-output (MISO) orthogonal frequency division multiple access (OFDMA) multicell networks, where a set of base stations cooperate to serve a set of ultra-reliable low-latency communication (URLLC) users. The IRS is deployed to enhance the communication channel and increase reliability by creating a virtual line of sight for URLLC users with unfavorable propagation conditions. This is the first study on IRS-enhanced OFDMA-URLLC systems. The resource allocation algorithm design is formulated as an optimization problem for the maximization of the weighted system sum throughput while guaranteeing the quality of service of the URLLC users. The optimization problem is non-convex and finding the globally optimal solution entails a high computational complexity which is not desirable for real-time applications. Therefore, a suboptimal iterative algorithm is proposed which \textit{jointly} optimizes all optimization variables in each iteration using a new iterative rank minimization approach. The algorithm is guaranteed to converge to a locally optimal solution of the formulated optimization problem. Our simulation results show that the proposed IRS design facilitates URLLC and yields large performance gains compared to two baseline schemes.