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不断增长，必须访问“毫米波”频段的大量可用频谱，这比目前WiFi和蜂窝系统中使用的频段高几个数量级。最近已经取得了重大进展，证明了采用低成本硅半导体工艺构建射频集成电路（rfic）的可行性，适用于较低毫米波频段，如28 GHz授权频谱（用于5G蜂窝）和60 GHz非授权频谱（用于下一代WiFi）。该项目旨在提供超越这些努力的量子飞跃，开发具有战略重要性和商业可行性的技术，以开放超过100 GHz的上毫米波频段。具体目标是开发具有数千个元件的天线阵列，能够形成灵活的铅笔波束跟踪移动设备，由于100+ GHz的微小波长，可以将其小型化成紧凑的形状。该项目研究了用于扩展阵列尺寸的硬件和算法协同设计的新方法，目标是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，光纤的固定无线替代方案为100 Gbps）。毫米波（mmWave）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基本瓶颈是封装：由于天线之间半波长间隔的标准限制，在小载波波长下“装配”RFIC电子器件变得困难。该项目研究了新颖的硬件架构，绕过这些封装瓶颈，实现大规模扩展阵列，以及全数字分层信号处理架构的紧密耦合创新，目标是容量和弹性的量子飞跃。硬件研究包括开发极低成本的140GHz收发模块阵列技术，该技术易于扩展到具有大量元素的阵列。信号处理和系统研究开发了与平铺式硬件架构相匹配的全数字分层信号处理架构，说明了规范多用户（MU） MIMO和视线（LoS） MIMO设置中扩展阵列提供的鲁棒性和额外空间自由度的系统级影响，旨在灵活、经济地部署接入和回程节点。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信号的数量，从而通过牺牲动态范围来简化功耗和芯片面积。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。

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.