Collaborative Research: Applied Electromagnetic Characterization of Wideband Multi-Array Communication

该合作项目（与UT-Austin的Heath合作，提案03-22975）对多输入多输出（MIMO）系统进行了实验研究，旨在设计和测试宽带数字无线通信系统的新型天线系统，为设计人员提供新的数据点。实验程序分为两个测试台。第一个测试平台（在Drexel实施）专注于MIMO信道的电磁传播特性，而第二个测试平台（在UT-Austin实施）利用电磁特性来检查更高网络层的信道影响。由于对高速和高质量移动的通信的需求不断增长，具有MIMO通信链路的系统使用多个天线阵列，一个在发射机处，一个在接收机处，以利用传播信道的空间维度。当适当设计时，多阵列通信链路除了减少信道变化之外还可以提供链路吞吐量的多倍增加，这又可以用于向单个用户提供更高的速率、更低的延迟链路，或者允许多个用户在空间信道中共存。由于这些优点，MIMO能力正被考虑用于室内局域网（LAN）、蜂窝多媒体数据网络和宽带无线接入。然而，在没有仔细设计的情况下，电磁相互作用的结果（诸如互耦合）可能使信道系数相关，从而导致容量或错误概率方面的损失。需要真实的实验传播和实验数据来关联不同天线设计、天线放置、散射模型、信道带宽和收发器算法之间的权衡。本研究设计并建立两个实验平台，分别用于宽带MIMO传播信道测量与实时原型制作。在德雷克塞尔建造的原型将用于MIMO传播信道的低水平电磁特性，而UTA原型将用于证明这种特性对高层的影响。因此，该项目的工作包括评估和分析宽带MIMO传播信道，互耦和电磁相互作用导致的性能损失，以及研究天线分布在整个环境中的先进MIMO架构。该研究计划涉及现场实验与原型硬件的协同作用，并得到计算电磁（CEM）建模和通信理论的支持。 将通信和应用电磁学的概念联合引入高级本科生和研究生课程（而不是作为单独的课程），部署在两所大学联合授课的跨学科课程模块，生成包含一系列实验和一组课堂笔记的实验室手册，提供收集的数据记录，说明对设计至关重要的概念，使其他大学的教师能够将一些实验方法纳入他们的教学中。

This collaborative project (with Heath at UT-Austin, proposal 03-22975), performing an experimental investigation of Multiple-Input Multiple-Output (MIMO) systems, aims at designing and testing novel antenna systems for wideband digital wireless communication systems to provide designers with new data points. The experimental program is divided between two testbeds. The first testbed (implemented at Drexel) focuses on the electromagnetic propagation characteristics of the MIMO channel, while the second testbed (implemented at UT-Austin) makes use or the electromagnetic characterization to examine the channel impact of the higher network layers. Systems with MIMO communication links, fueled by the increasing demand for high-speed and high-quality mobile communication, use multiple antenna arrays, one at the transmitter and one at the receiver, to take advantage of the spatial dimension of the propagation channel. When properly designed, multi-array communication links can provide multi-fold increases in link throughput in addition to reductions in channel variation which in turn may be used to provide higher rates to single users, lower delay links, or to allow multiple users to coexist in the spatial channel. Because of this advantages, MIMO capability is being considered for indoor local area networks (LAN)s, cellular multimedia data networks, and broadband wireless access. However, without careful design, the results of electromagnetic interaction, such as mutual coupling, may correlate the channel coefficients, thus resulting in a loss in terms of capacity or error probability. Real experimental propagation and experimental data are needed to correlate the tradeoffs between different antenna designs, antenna placements, scattering models, channel bandwidth, and transceiver algorithms. This research involves designing and building two experimental platforms for wideband MIMO propagation channel measurement and real-time prototyping. The prototype constructed at Drexel will be used for the low-level electromagnetic characterization of the MIMO propagation channel, while the UTA prototype will be used to demonstrate the impact of this characterization on higher layers. Thus the work involves Estimating and analyzing wideband MIMO propagation channels, Verifying performance loss due to mutual coupling and electromagnetic interactions, and Studying advanced MIMO architectures in which the antennas are distributed throughout the environment.The research plan involves a synergy of field experimentation with prototype hardware backed by computational electromagnetic (CEM) modeling and communication theory.Broader impacts are addressed in several ways: Introducing jointly concepts of communications and applied electromagnetics to advanced undergraduate and graduate courses (rather than as separate courses), Deploying interdisciplinary course modules jointly taught at both universities, generating a lab manual containing a series of experiments and a set of lecture notes, Providing the data records collected that illustrate concepts critical to design, and Enabling instructors at other universities to incorporate some experimental methods into their teaching.