EAGER: Advanced Wireless Communication Concepts Applied to Optical Fibers

我们试图研究为无线通信开发的先进的信令和处理概念在多模光纤传输系统中的应用。传统上，可实现的最大数据速率受到光纤距离带宽乘积的限制；然而，多输入多输出信令通过牺牲色散的基本限制来实现带宽的显著增加，这是众所周知的计算练习。我们的初步实验结果超过了传统调制方案的24倍以上，可能会有数量级的额外性能，特别是在误码率方面。在本计划中，我们寻求通过(1)使用现成组件构建低成本、可扩展的试验台和(2)开发完整的理论框架来扩展我们对这一新领域的实验和理论理解。由于数据中心依赖机架到机架和板到板级别的多模光纤链路，因此极大地提高低成本光纤链路的带宽的潜力对数据中心尤其具有吸引力。一种大大增加可实现的带宽并降低每比特能量损失的方法将是真正可行的。在全国各地的局域网中，也有大量预先存在的多模光纤部署。由于组件成本较高，在许多情况下，用单模光纤网络取代这种多模基础设施作为满足未来带宽需求的一种手段，成本是令人望而却步的。使用我们的方法，这种系统的带宽可以升级，而不需要求助于单模光纤。此外，未来的光驱动、光飞和光学舰载系统也可以使用这种方法；与传统的电子信号相比，这种系统具有吸引力，因为它可以极大地降低体积、重量、功率和对电磁干扰的敏感度。我们认为，这种努力非常适合渴望的人，因为(1)目标可以快速且适度低的成本实现；(2)它与传统的光纤通信方法有很大的不同，仍然存在许多基本问题，使得几乎不可能通过传统机制获得资金；(3)这种努力是高度跨学科的(例如，PI Bank是一名光子器件和材料工程师，而Co-Pi Vishwanath是一名信息理论家)；以及(4)在回答上述问题后，这种方法可以很容易地过渡到更传统的融资机制。智能的优点在于推进了与将无线通信方法应用于多模光纤相关的理论基础和实验结果。为此，我们将开发一个多模光纤上多输入多输出通信的建模框架。这一分析将把信息论和统计信号处理的工具与光子学的工具结合起来。在这些学科的交叉点上，我们的工作有限，我们的努力将在开发一个描述多模光纤通信基本限制的综合框架方面取得重大进展。我们将利用这一理论来设计非常适合利用多输入多输出策略的潜在好处的新型设备。我们还将使用现成的组件构建一个系统测试台，以研究性能如何随发射器和接收器的数量而变化，为理论分析提供有价值的反馈。在这项工作结束时，我们希望展示在光纤通信领域的真正使能能力，以及无数潜在的新应用。除了我们将通过期刊出版物和会议演讲传播的研究成果外，我们还寻求让高中、本科生和研究生参与光纤通信系统的概念和含义、其基本基础以及严格验证和评估的重要性。为此，PI将开发演示和演示，通过德克萨斯大学奥斯汀分校、S爱迪生系列讲座、夏季纳米科学学院和UTeach等机制，吸引德克萨斯州的高中生和教师。我们还将开发关于光通信的新的本科生研究项目，以增强NSF-REU网站EURECA的产品，该网站由联合-Pi Vishwanath指导。这项计划的目标是德克萨斯州各大学招收的代表人数不足的群体的参与者。此外，作为团队的一部分？S对国家的承诺？S学生社区，由PI生成的讲座将被转换为课程模块，并通过德克萨斯大学在线提供？世界大讲堂网站。

We seek to investigate the application of advanced signaling and processing concepts, which have been developed for wireless communication, to multimode fiber-optic transmission systems. Traditionally, the maximum achievable data rate is limited by the distance-bandwidth product of the fiber; however, multiple-input multiple output signaling enables significant increases in bandwidth, by trading the fundamental limitations of dispersion for a computational exercise that that is well-understood. Our preliminary experimental results exceed what is achievable with traditional modulation schemes by over 24-fold, with the potential for orders of magnitude in additional performance, particularly with regard to bit-error-rate. In this program, we seek to expand our experimental and theoretical understanding of this new field by (1) building a low-cost, scalable, testbed using off-the-shelf components and (2) developing a complete theoretical framework.The potential for greatly enhancing the bandwidth of low-cost optical links is particularly compelling for data centers as they rely on multimode fiber links at the rack-to-rack and board-to-board level. A method to greatly increase the achievable bandwidths and reduce the energy-per-bit penalty would be truly enabling. There are also substantial pre-existing deployments of multimode fiber in local area networks across the nation. Due to higher component costs, it is cost-prohibitive in many cases to replace this multimode infrastructure with single-mode fiber networks, as a means to meet future bandwidth demands. Using our approach, the bandwidth of such systems can be upgraded without resorting to single-mode fibers. Additionally, future drive-by-light, fly-by-light, and optical shipboard systems could also be enabled with this approach; such systems are attractive because of the potential to greatly reduce size, weight, power, and sensitivity to electromagnetic interference, as compared with conventional electrical signaling. We believe that this effort is ideally suited to an EAGER because (1) the goals can be achieved rapidly and at moderately low cost; (2) it is a dramatic departure from conventional fiber-optic communication approaches with many fundamental questions remaining, rendering it virtually impossible to obtain funding through conventional mechanisms; (3) the effort is highly interdisciplinary (e.g. PI Bank is a photonic device and materials engineer, while Co-PI Vishwanath is an information theorist); and (4) upon answering the aforementioned questions, this approach can readily transition to more conventional funding mechanisms.Intellectual Merit. The intellectual merit lies in advancing the theoretical underpinnings and experimental findings associated with the application of wireless communication approaches to multimode fibers. To this end, we will develop a framework for modeling multiple-input multiple-output communication over multimode fiber. This analysis will merge tools from information theory and statistical signal processing with those from photonics. There is limited work at the intersection of these disciplines and our efforts will make significant inroads into developing a comprehensive framework for characterizing the fundamental limits of multimode fiber communications. We will leverage this theory to design novel devices that are ideally suited to harnessing the potential benefits of multiple-input multiple-output strategies. We will also construct a system testbed using off-the-shelf-components, to study how performance scales with the number of transmitters and receivers, providing valuable feedback to the theoretical analysis.Broader Impact. At the conclusion of this effort, we expect to demonstrate truly enabling capabilities in optical fiber communications, with myriad potential new applications. In addition to our research findings, which will be disseminated through journal publications and conference talks, we also seek to engage students at the high school, undergraduate, and graduate levels on the concepts and implications of optical fiber communication systems, their underlying foundations, and the importance of rigorous validation and evaluation. To this end, the PIs will develop presentations and demonstrations to engage high school students and teachers across Texas, through mechanisms including UT-Austin?s Edison Lecture Series, Summer Nanoscience Academy, and UTeach. We will also develop new undergraduate research projects on optical communications, to enhance the offerings of the NSF-REU site EURECA, directed by co-PI Vishwanath. This program targets participants from underrepresented groups enrolled at universities across the state of Texas. Additionally, as part of the team?s commitment to the nation?s student community, lectures generated by the PIs will be converted into course modules and made available online through The University of Texas? World Lecture Hall website.