RINGS: Massive Extended-Array Transceivers for Robust Scaling of All-Digital mmWave MIMO

随着对高速无线数据的需求持续增长，接入“毫米波”频段的大量频谱至关重要，这些频段比当今WiFi和蜂窝系统中使用的频段高出几个数量级。最近取得了实质性进展，证明了使用低成本硅半导体工艺构建的射频集成电路(RFIC)对于较低的毫米波频段的可行性，例如28 GHz许可频谱(用于5G蜂窝)和60 GHz非许可频谱(用于下一代WiFi)。该项目旨在提供超越这些努力的巨大飞跃，开发具有战略重要性和商业可行性的技术，以打开100 GHz以上的上毫米波频段。一个具体的目标是开发具有数千个单元的天线阵列，能够形成跟踪移动设备的灵活的铅笔波束，由于100+GHz的微小波长，可以将其微型化为紧凑的外形因素。该项目研究了硬件和算法协同设计的新方法，以实现可实现的链路距离和数据速率的显著跃升(城市小区中每个移动用户10 Gbps，固定无线光纤替代品100 Gbps)。毫米波(毫米波)通信将在下一代通信基础设施中发挥关键作用。毫米波硬件开发的一个根本瓶颈是封装：由于天线之间半波长间距的标准限制，在小载波波长下“安装”RFIC电子变得困难。该项目研究绕过这种封装瓶颈以实现大规模扩展阵列的新型硬件体系结构，以及全数字分层信号处理体系结构中紧密耦合的创新，目标是在容量和弹性方面实现量子飞跃。硬件研究包括开发极低成本的140 GHz收发器模块化阵列瓦片技术，这些技术很容易扩展到具有大量元件的阵列。信号处理和系统研究开发了与平铺硬件体系结构匹配的全数字分层信号处理体系结构，说明了在旨在灵活、经济高效地部署接入和回程节点的规范多用户(MU)MIMO和视距(LOS)MIMO设置中，扩展阵列提供的健壮性和额外空间自由度对系统级的影响。一个关键的设计概念是空间冗余：通过选择硬件和系统参数，使阵列射频通道的数量大大超过所涉及的MIMO信号数量，可以通过牺牲动态范围来简化功耗和芯片面积。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

As the demand for high-speed wireless data keeps growing, it is essential to access the vast amounts of spectrum available in “millimeter wave (mmWave)” frequency bands, which are orders of magnitude higher than the frequency bands used in WiFi and cellular systems today. There has been substantial recent progress demonstrating feasibility of radio frequency integrated circuits (RFICs) built with low-cost silicon semiconductor processes, for lower mmWave frequency bands such as 28 GHz licensed spectrum (for 5G cellular), and 60 GHz unlicensed spectrum (for next-generation WiFi). This project aims to provide a quantum leap beyond these efforts, developing strategically important and commercially viable technologies for opening up upper mmWave bands beyond 100 GHz. A specific goal is to develop antenna arrays with thousands of elements, capable of forming agile pencil beams tracking mobile devices, which can be miniaturized into compact form factors because of the tiny wavelengths at 100+ GHz. The project investigates novel approaches for co-design of hardware and algorithms for scaling array sizes, targeting significant jumps in attainable link distances and data rates (10 Gbps per mobile user in an urban cell, and 100 Gbps for a fixed wireless alternative to fiber).Millimeter wave (mmWave) communication will play a crucial role in next-generation communication infrastructures. A fundamental bottleneck in mmWave hardware development is packaging: “fitting” the RFIC electronics becomes difficult at small carrier wavelengths due to the standard constraint of half-wavelength spacing between antennas. This project investigates novel hardware architectures that sidestep such packaging bottlenecks to realize massive extended arrays, along with closely coupled innovations in all-digital hierarchical signal processing architectures, targeting quantum leaps in capacity and resilience. Hardware research includes development of extremely low-cost 140GHz transceiver modular array tile technologies that readily scale to arrays having vast numbers of elements. Signal processing and systems research develops all-digital hierarchical signal processing architectures matched to the tiled hardware architecture, illustrating the system-level impact of the robustness and additional spatial degrees of freedom provided by extended arrays in canonical multiuser (MU) MIMO and Line of Sight (LoS) MIMO settings aimed at flexible, cost-effective deployment of access and backhaul nodes. A key design concept is spatial redundancy: by choosing hardware and system parameters such that the number of array RF channels greatly exceeds the number of MIMO signals involved, it becomes possible to simplify power consumption and die area by sacrificing dynamic range.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.