论文标题
智能反射表面的综合主动/被动无线网络有助于系统建模和性能分析
Hybrid Active/Passive Wireless Network Aided by Intelligent Reflecting Surface: System Modeling and Performance Analysis
论文作者
论文摘要
智能反射表面（IRS）是一种新的且有希望的范式，可通过通过调整大量的低成本被动反射元素来构建有利的沟通渠道，从而实质上提高无线网络的光谱和能源效率。尽管在各种IRS辅助无线系统的链接级绩效优化方面取得了最新进展，但如果在无线网络中大规模部署IRS可以成为未来实现其可持续能力增长的解决方案，仍然仍然是一个开放的问题。为了解决这个问题，我们在本文中研究了一个新的混合无线网络，该网络既包括主动基站（BSS）和被动IRSS，并在下行链路以及其他相关的关键性能指标中表征了其可实现的空间吞吐量，以及在部署的BSS/IRSS/IRSS/irss inters of Sentered bss/irss interss inters inters of s in stern in conthing ncochastic conterins inters conterin的渠道褪色和随机位置的平均度量。与仅具有活性BS的无线网络性能的先前工作相比，我们的分析需要得出在空间相关的通道下，网络中分布式IRS反射的信号和干扰的功率分布，当IRS元素的数量变得较大时，该通道效果显示出通道硬化的效果。提出了广泛的数值结果，以验证我们的分析，并证明了部署分布式IRS在没有IRS的传统网络中增强混合网络吞吐量的有效性，这显着增强了信号功率，但仅导致网络中的干扰略有增加。此外，据推测，存在最佳的IRS/BS密度比，从而使混合网络吞吐量以其个人成本为主的总部署成本，而没有IRS的常规网络通常以每单位成本的吞吐量为单位。
Intelligent reflecting surface (IRS) is a new and promising paradigm to substantially improve the spectral and energy efficiency of wireless networks, by constructing favorable communication channels via tuning massive low-cost passive reflecting elements. Despite recent advances in the link-level performance optimization for various IRS-aided wireless systems, it still remains an open problem whether the large-scale deployment of IRSs in wireless networks can be a cost-effective solution to achieve their sustainable capacity growth in the future. To address this problem, we study in this paper a new hybrid wireless network comprising both active base stations (BSs) and passive IRSs, and characterize its achievable spatial throughput in the downlink as well as other pertinent key performance metrics averaged over both channel fading and random locations of the deployed BSs/IRSs therein based on stochastic geometry. Compared to prior works on characterizing the performance of wireless networks with active BSs only, our analysis needs to derive the power distributions of both the signal and interference reflected by distributed IRSs in the network under spatially correlated channels, which exhibit channel hardening effects when the number of IRS elements becomes large. Extensive numerical results are presented to validate our analysis and demonstrate the effectiveness of deploying distributed IRSs in enhancing the hybrid network throughput against the conventional network without IRS, which significantly boosts the signal power but results in only marginally increased interference in the network. Moreover, it is unveiled that there exists an optimal IRS/BS density ratio that maximizes the hybrid network throughput subject to a total deployment cost given their individual costs, while the conventional network without IRS is generally suboptimal in terms of throughput per unit cost.
