Excellence in Research: Artificial Intelligence Aided Metasurface Design and Application in Next Generation of Cellular Communication Systems

在当前的无线通信系统范例中，无线电传播环境通常被视为不受控制和不可预测的方面。由于无线电环境中不可预测的变化，信号传输在到达接收器之前会遇到反射、衍射和散射，其中包含许多衰减和延迟分量的副本。该项目将探索如何设计一个由超材料组成的智能反射面（IRS），部署在下一代蜂窝通信系统中，以调整无线环境，从而实现智能和可重构的无线信道，以提高网络吞吐量和能源效率。IRS通常是由大量被动反射元件（PREs）组成的平面，每个被动反射元件都可以分别对输入信号的幅度和相位产生可调节的变化。因此，从发射节点发出的电磁波可以通过IRS以一种允许它们在通往接收节点的途中利用更有利的传播环境的方式进行反射。通过在无线网络中密集部署IRSs并智能地协调其反射，无线系统可以增加在发射机和接收机节点之间实现视距（LOS）传播路径的可能性，同时最大限度地减少同信道和小区间干扰的影响，并优化通信系统的能源效率。然而，irs辅助通信系统的成功实现需要从无线通信和设备的电磁建模两方面综合考虑相干设计因素。在这个项目中进行的结果和分析将允许电磁学、多物理场和无线通信研究人员将开发的想法扩展到应用场景。该项目将设计、开发和分析人工智能（AI）驱动的创新方法，以解决irs辅助通信系统发射机和接收机基带信号处理固有的基本挑战。通过开发全面创新的数值建模和仿真框架，将可重构技术和新型元表面的能力集成到设计和应用新的IRS设备中。为了提高irs辅助下一代蜂窝通信系统的网络吞吐量，将通过考虑无线通信和设备物理的设计约束，提出跨功能资源分配方案。窄带和宽带信道都将被视为进行系统调查，并将提出新的设计方法，在解决实际设计限制的同时，执行接近理论性能。所提出的方法将在仿真框架中实施，并与最先进的方法进行比较，以显示其在无线通信系统中的有效性。这些研究工作将鼓励下一代蜂窝通信系统的有效系统设计和算法开发，并协助产品和算法工程师和研究人员利用IRS。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The radio propagation environment is typically viewed as an uncontrolled and unpredictable aspect in the current wireless communication system paradigm. Because of the unpredictable changes in the radio environment, signal transmission encounters reflections, diffractions, and scattering before arriving at the receiver with numerous copies of attenuated and delayed components. This project will explore how to design an intelligent reflecting surface (IRS) comprised of metamaterials to deploy in the next generation of cellular communication systems to tune the wireless environment and hence achieve intelligent and reconfigurable wireless channels to increase network throughput and energy efficiencies. IRS is typically a flat surface made of a large number of passive reflecting elements (PREs), each of which can generate a regulated change in the amplitude and phase of the incoming signal separately. As a result, electromagnetic waves emanating from the transmitter nodes can be reflected by IRS in a manner that allows them to take advantage of a more favorable propagation environment en route to the reception nodes. By densely deploying IRSs in wireless networks and intelligently coordinating their reflections, wireless systems can increase the likelihood of achieving a line-of-sight (LOS) propagation path between transmitter and receiver nodes while minimizing the impact of co-channel and inter-cell interference and optimizing the energy efficiency of the communication system. However, a successful accomplishment of an IRS-aided communication system requires considering coherent design factors jointly from wireless communications and electromagnetic modeling of devices. The results and analysis conducted in this project will allow electromagnetics, multiphysics, and wireless communication researchers to extend the developed idea to application scenarios.This project will design, develop, and analyze artificial intelligence (AI) driven innovative approaches to address fundamental challenges inherent to baseband signal processing at transmitter and receiver for IRS-aided communication systems. The capability of reconfigurable technologies and novel metasurfaces will be integrated to design and apply new IRS devices by developing a comprehensive and innovative numerical modeling and simulation framework. To enhance the network throughput for an IRS-aided next-generation cellular communication system, cross-functional resource allocation schemes will be proposed by considering design constraints from wireless communications and device physics. Both narrowband and wideband channels will be regarded to conduct this systematic investigation, and novel design approaches will be proposed that perform close to theoretical performance while addressing practical design constraints. The proposed methods will be implemented in a simulation framework and compared with the state-of-the-art approaches to show their effectiveness in wireless communication systems. These research works will encourage efficient system design and algorithm development for the next generation of cellular communication systems and assist product and algorithm engineers and researchers utilizing IRS.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.