TCHCS: COLLABORATIVE RESEARCH: Millimeter-wave MIMO: A New Architecture for Integrated 10-40 Gigabit Wireless/Optical Hybrid Networks

ECS-0636594 Chik Yue，Carnegie Mellon UniversityECS-0636621 Upamanyu Madhow，University of Santa Barbara我们的目标是开发系统架构、信号处理算法和集成电路技术，用于使用毫米波频谱在几公里范围内实现10-40 Gbps的速度的鲁棒、快速建立的点对点无线链路。由于这些速度与光纤相当，该项目的成果使故障安全的混合通信骨干基础设施成为可能，可以在发生灾难和紧急情况时迅速部署或恢复。该系统采用了一种新型的分层架构，该架构将波束成形（提供足以克服恶劣天气下毫米波传播限制的链路裕度）和空间复用（提供每秒数十位/赫兹量级的高频谱效率，这是实现所需的）相结合。使用仅几GHz的信道带宽实现光链路速度）。波束形成增益是通过电子可操纵的单片阵列获得的。每个这样的阵列是较大阵列中的子阵列，形成空间复用虚拟多输入多输出（MIMO）系统：发射子阵列发送单独的数据流，这些数据流在接收器处使用空间干扰抑制技术分离出来。该毫米波MIMO系统的关键要素是用于单片可操纵子阵列的CMOS IC设计、用于获得可在如此高的速度下实现的算法的信号处理/硬件协同设计以及用于实现低功耗操作的混合模拟/数字处理。大量的努力将进入建立一个基于单元的，可重复使用的设计/建模框架，使CMOS毫米波VLSI设计。新的发现将通过小型设计项目纳入本科生和研究生课程。智力优势：这是一个本质上的跨学科项目，其成功关键取决于该项目的三个PI之间的密切互动，其综合专业知识涵盖通信应用CMOS IC设计（Yue），毫米波器件和IC设计（Rodwell）以及通信信号处理（Madhow）。所提出的系统是基于创新的每一个层面，包括系统概念，信号处理算法，电路设计和封装。毫米波MIMO在视线环境中提供空间复用，因此相对于仅在丰富散射环境中提供空间复用的较低频率处的MIMO是全新的概念。电子可操纵的子阵列是基于一个独特的行-列架构服从单片实现。信号处理方面的创新包括大幅简化，包括与硬件共同设计的分层分解。毫米波频率的电路设计推动了低成本CMOS工艺中混合信号设计的极限，我们基于单元的设计框架有可能为这种设计提供一种系统的方法。基带处理采用新颖的混合模拟/数字处理技术，以最小化对高速、高成本、高功率模数转换器的性能要求。更广泛的影响：毫米波MIMO提供了第一个可行的方法来弥合无线和光学系统之间的容量差距，其应用范围从国土安全（例如，灾难恢复）到企业和住宅环境的最后一英里连接。另一个突破是在LOS室外链路的部署的容易性方面，这变成了将发射机和接收机粗略地指向彼此的简单操作，而不是像当前实践中那样精确地对准发射天线和接收天线。此外，毫米波CMOS电路设计和封装方面的突破所需的这一要求苛刻的应用有可能产生的影响远远超出这里考虑的具体系统，并将开辟一个主机的机会，利用毫米波频谱在合理的成本。这些项目执行机构都有很好的技术转让记录，并打算利用其与通信行业的密切联系，不仅通过出版物，而且还利用参观者容易获得的硬件演示，广泛传播这项工作的成果，以推动技术转让。拟议的研究将对PI机构的本科生和研究生课程产生重大影响，推动电路设计和通信系统课程的创新和更新。将利用纳米技术领域完善的外联机制，让妇女和少数群体，包括高中生参与这项工作。由于该项目固有的跨学科性质，参与的学生将接受跨越电气和计算机工程几个领域的广泛教育。

ECS-0636594Chik Yue, Carnegie Mellon UniversityECS-0636621Upamanyu Madhow, University of Santa BarbaraOur objective is to develop the system architecture, signal processing algorithms and integrated circuit techniques for a robust, quick set-up, point-to-point wireless link which achieves speeds of 10-40 Gbps over a range of several kilometers, using millimeter (mm) wave spectrum. Since these speeds are comparable to those of optical fiber, the outcome of this project enables a fail-safe hybrid communication backbone infrastructure, which can be deployed or restored rapidly in the events of disaster and emergency. The system employs a novel hierarchical architecture which meshes beamforming (to provide link margins sufficient to overcome the limitations of mm-wave propagation in harsh weather) and spatial multiplexing (to provide large spectral efficiency, of the order of tens of bits per second per Hertz, required to realize optical link speeds using channel bandwidths of only several GHz). Beamforming gains are obtained by electronically steerable monolithic arrays. Each such array is a subarray in a larger array, forming a spatially multiplexed virtual multiple-input, multiple-output (MIMO) system: the transmit subarrays send separate data streams, which are separated out at the receiver using spatial interference suppression techniques. Key elements of this mm-wave MIMO system are CMOS IC design for monolithic steerable sub-arrays, signal processing/hardware co-design to obtain algorithms implementable at such high speeds, and hybrid analog/digital processing to enable low-power operation. Substantial effort will go into establishing a cell-based, reusable design/modeling framework to enable CMOS mm-wave VLSI design. The new findings will be incorporated into undergraduate and graduate classes through small design projects. Intellectual Merit: This is an inherently interdisciplinary project whose success depends critically on intense interaction between the three PI's on this project, whose combined expertise spans CMOS IC design for communication applications (Yue), millimeter wave device and IC design (Rodwell) and signal processing for communication (Madhow). The proposed system is based on innovations at every level, including system concept, signal processing algorithms, and circuit design and packaging. Millimeter-wave MIMO provides spatial multiplexing in line of sight environments, and is therefore a completely new concept relative to MIMO at lower frequencies, which provides spatial multiplexing only in rich scattering environments. The electronically steerable sub-arrays are based on a unique row-column architecture amenable to monolithic realization. The innovation in the signal processing consists of drastic simplifications, including a hierarchical decomposition co-designed with the hardware. Circuit design at mm-wave frequencies push the limits of mixed signal design in low-cost CMOS processes, and our cell-based design framework has the potential of providing a systematic approach to such design. The baseband processing employs novel hybrid analog/digital processing techniques, in order to minimize the performance requirements on high-speed, high-cost, high-power analog-to-digital converters.Broader Impact: Millimeter-wave MIMO provides the first feasible approach to bridging the capacity gap between wireless and optical systems, which has applications ranging from homeland security (e.g., disaster recovery) to last mile connectivity for enterprise and residential settings. An additional breakthrough is in terms of the ease of deployment of LOS outdoor links, which becomes a simple operation of roughly pointing the transmitter and receiver at each other, rather than precisely aligning the transmit and receive antennas as done in current practice. In addition, the breakthroughs in mm-wave CMOS circuit design and packaging required by this demanding application have the potential for impact well beyond the specific system considered here, and will open up a host of opportunities for harnessing mm-wave spectrum at reasonable cost. The PIs all have strong records of technology transfer, and intend to leverage their strong contacts with the communications industry to push for technology transfer by widely disseminating the results of this work not only through publications, but also using hardware demonstrations easily accessible to visitors. The proposed research will have a significant impact on the undergraduate and graduate curriculum at the PIs' institutions in terms of driving innovations and updates in a number of courses in circuit design and communication systems. Well-established outreach mechanisms in the nanotech area will be used to involve women and minorities, including high school students, in this effort. Due to the inherently interdisciplinary nature of this project, the students involved will receive a broad education cutting across several areas of Electrical and Computer Engineering.