EAGER: Proof-of-Concept of a New MIMO Transceiver for Addressing Beam Squint in Wideband High-Dimensional Arrays

提案编号1546604：EIGER：一种用于解决宽带高维天线阵列无线通信中基本波束斜视问题的新系统架构无线技术即将迎来一场根本性的变革。工作在厘米波(10-30 GHz)和毫米波(30-300 GHz)频率的新系统是当前密集研究的焦点，以满足爆炸性的无线数据业务需求。有两个因素使这样的高频具有吸引力：i)数量级的较大可用频谱块，以及ii)由小波长实现的高维天线阵列。由此产生的大量自由度可以用于许多关键能力，包括与窄的高增益波束进行高度定向通信，以及通过多个波束同时向多个用户传输宽带来实现频谱的空间重用。然而，波束形成前端的硬件复杂性和后端数字处理的计算复杂性挑战了当前的数字范例，需要对高维模拟-数字接口的设计进行全新的审视。在新兴的毫米波和连续波系统中，其对性能的影响不能再被忽视的一个基本问题是众所周知的“波束斜视”问题--波束方向作为频率的函数变化。传统的解决方案过于复杂，无法在实践中实现。这个为期两年的急切项目的目标是提供一种新的多波束系统架构的概念验证，与传统设计相比，该架构承诺提供接近最佳的性能和显著降低的复杂性。该项目将为无线通信尖端领域的研究生和本科生提供宝贵的研究和培训机会，包括基础理论和基于原型的实验。新的架构已经申请了专利，预计它将在新兴的用于CMW和MMW应用的宽带多天线技术的构思和开发中发挥重要作用。这项技术还可能影响雷达的应用。这项拟议的研究利用了通信理论、信号处理、优化、谐波分析、天线设计和传播物理等工具。从一个新的角度重新审视了波束斜视问题，量化了波束斜视对性能的重要影响，并提出了有效处理该问题的新的多波束系统架构。由PI开创的波束空间理论为使用多天线阵列的多输入多输出(MIMO)无线系统的设计和分析提供了新的视角。目前正在进行一项综合的理论-实验研究计划，总体目标有两个：一)开发新系统架构的基础理论；二)使用10 GHz的原型进行概念验证。基础理论的发展将描述新的多波束(MB)MIMO收发信机在所有点对点系统配置中的特点。它将能够更全面地量化拟议的宽带MB-MIMO收发机相对于传统相控阵系统的性能收益，以及它们所提供的性能与复杂性之间的权衡。概念验证演示将使用带有透镜天线的原型进行模拟波束形成。该项目的结果将为宽带高维MIMO系统中的性能复杂性优化提供新的MB-MIMO结构的明确概念证明，其中波束斜视是一个重要问题。这一项目的成果有望在无线通信和宽带高维阵列传感这一关键新兴领域带来新的研究成果。

Proposal no. 1546604: EAGER: A New System Architecture for Addressing the Fundamental Beam-Squint Problem in Wireless Communication with Wideband High-Dimensional Antenna Arrays Wireless technology is poised for a radical transformation. New systems operating at centimeter-wave (10-30GHz) and millimeter-wave (30-300GHz) frequencies are the focus of intense current research to meet the exploding wireless data traffic demands. Two factors make such high frequencies attractive: i) order-of-magnitude larger chunks of available spectrum, and ii) high-dimensional antenna arrays enabled by the small wavelengths. The resulting large number of degree of freedom can be exploited for a number of critical capabilities, including highly directional communication with narrow high-gain beams, and spatial reuse of the spectrum by simultaneous wideband transmissions to multiple users through multiple beams. However, the hardware complexity of the beamforming front-end and the computational complexity of the back-end digital processing challenge the current "digital" paradigm and require a fresh look at the design of the high-dimensional analog-digital interface. One fundamental problem whose impact on performance can no longer be ignored in emerging mmW and cmW systems is the well-known ``beam-squint'' problem - the beam direction changes as a function of frequency. Traditional solutions are far too complex to be realized in practice. The objective of this two-year EAGER project is to provide proof-of-concept of a new multi-beam system architecture that promises to deliver near-optimal performance with dramatically reduced complexity compared to conventional designs. The project will provide an invaluable research and training opportunity for graduate and undergraduate students at the cutting edge of wireless communications, including basic theory and prototype-based experimentation. A patent has been filed on the new architecture and it is expected to play an important role in the conception and development of emerging wideband multi-antenna technology for cmW and mmW applications. The technology could also impact radar applications.The proposed research draws on tools from communication theory, signal processing, optimization, harmonic analysis, antenna design, and physics of propagation. It is prompted by promising initial results that revisit the beam-squint problem from a new perspective, quantify its significant impact on performance, and suggest the new multi-beam system architecture for effectively dealing with it. The new perspective is offered by a beamspace theory, pioneered by the PI, for the design and analysis of multiple input multiple output (MIMO) wireless systems that employ multi-antenna arrays. An integrated theoretical-experimental research plan is being pursued with two overall objectives: i) development of basic theory for the new system architecture, and ii) proof-of-concept validation using a prototype at 10GHz. The development of basic theory will characterize the new multi-beam (MB) MIMO transceivers in all point-to-point system configurations. It will enable a more complete quantification of the performance gains of the proposed wideband MB-MIMO transceivers relative to conventional phased array-based systems, as well as the performance-complexity tradeoffs offered by them. The proof-of-concept demonstration will use a prototype with a lens antenna for analog beamforming. The results of this project will provide a definitive proof-of-concept of the new MB-MIMO architecture for performance-complexity optimization in wideband high-dimensional MIMO systems in which beam-squint is a significant problem. The findings of this project are expected to lead to new research in the critical emerging area of wireless communication and sensing with wideband high-dimensional arrays.