MRI: Development of a Matrix Channel Measurement System

矩阵信道是一组NT NR个冲激响应（子信道），它完全表征了NT I个发射天线和NR I个接收天线之间的传播。俄亥俄州州立大学电子科学实验室（ESL）将开发矩阵通道测量系统（MCMS），该系统由一个移动的多通道发射机（MCT）和一个便携式多通道接收机（MCR）组成，能够在250 MHz和6 GHz之间的任何频率下进行带宽高达40 MHz的任何形式的调制。MCT将由4个独立的相干通道组成。每个发射通道将由任意波形发生器和上变频器组成。MCR将由16个通道组成，每个通道由下变频器/数字转换器、40 MHz带宽下的75 ms捕获（带宽越小，捕获时间越长）、实时数据处理和长期结果存储组成。MCT和MCR都将由电池供电，并内置于适合两人携带的运输箱中，以便在任何地方进行测量，包括室内，室外和车辆。MCMS将用于持续的ESL研究计划，包括：（1）矩阵信道中容量的测量，（2）频分双工（FDD）系统的开环前向链路阵列处理技术的开发和评估，（3）用于波束形成和移动的无线电地理定位的到达角（AOA）估计技术的改进，以及（4）用于GPS接收机的干扰减轻技术的评估。在每种情况下，MCMS的上级调谐范围、带宽、捕获时间和便携性将大大提高数据质量，相对于从ESL和其他公司开发的以前的系统获得的数据质量。例如，在主题1中，MCMS将用于获得矩阵信道的改进和更全面的测量，以支持下一代通信技术（如BLAST）的开发，这些技术利用天线阵列来显著提高频谱效率。特别感兴趣的是学习在什么条件下矩阵信道系统显着优于矢量（NT = 1）的信道方法，以及如何设计天线阵列（元素的几何形状和极化），以优化这种性能。MCMS将凭借其模块化的软件定义架构而具有前所未有的灵活性，因此对其他研究工作也具有巨大价值。尽管迫切需要，但商业上没有具有可比功能的系统，也不能以合理的成本从现成的设备中组装这样的系统。相反，项目小组将自下而上设计MCMS，利用其以前在开发类似系统方面的丰富经验。为了确保该项目的成功，ESL将与世界知名的定制射频测试设备开发商Aeroflex Lintek合作，共同开发MCMS。在这种合作关系中，ESL将负责硬件和软件的设计概念、要求、概念验证和原型设计。Aeroflex Lintek将参与设计工作，并负责系统工程和最终系统的开发。Aeroflex Lintek将以其预期成本的一小部分执行这项工作，以换取开发、生产和销售基于该项目开发的技术的新一代RE测试设备的机会。

AbstractA matrix channel is the set of NT NR impulse responses (subchannels) that completely characterize the propagation between NT I transmit antennas and NR I receive antennas. The Ohio State University ElectroScience Laboratory (ESL) will develop a matrix channel measurement system (MCMS), consisting of a mobile multichannel transmitter (MCT) and a portable multichannel receiver (MCR) capable of any form of modulation with bandwidth up to 40 MHz at any frequency between 250 MHz and 6 GHz. The MCT will consist of 4 independent, coherent channels. Each transmit channel will consist of an arbitrary waveform generator and an upconverter. The MCR will consist of 16 channels, with each channel consisting of a downconverter/digitizer, 75 ms capture at 40 MHz bandwidth (proportionally longer for smaller bandwidths), on-the-fly data processing, and long-term storage of results. Both the MCT and MCR will be battery-powered and built into transit cases suitable for two-person carry to allow measurements anywhere, including indoors, outdoors, and from vehicles.The MCMS will be employed in continuing ESL research programs including: (1) Measurements of capacity in matrix channels, (2) Development and evaluation of open loop forward link array processing techniques for frequency division duplex (FDD) systems, (3) Refinement of angle-of-arrival (AOA) estimation techniques for beamforming and mobile radio geolocation, and (4) Evaluation of interference mitigation techniques for GPS receivers. In each case, the superior tuning range, bandwidth, capture time, and portability of the MCMS will greatly enhance the quality of data relative to that obtained from previous systems developed by ESL and others. For example, in topic 1, the MCMS will be used to obtain improved and more thorough measurements of matrix channels to support development of the next generation of communications technologies, such as BLAST, that exploit antenna arrays to dramatically increase spectral efficiency. Of particular interest is learning under what conditions matrix channel systems significantly outperform vector (NT = 1) channel methods, and how to design antenna arrays (element geometry and polarization) to optimize this performance. The MCMS will possess unprecedented flexibility by virtue of its modular, software-defined architecture, and thus will be of great value for other research efforts as well.Despite the urgent need, no system with comparable features exists commercially, nor can such a system be assembled from off-the-shelf equipment at a reasonable cost. Instead, the project team will design the MCMS from the bottom up, bringing to bear its extensive previous experience in developing similar systems. To ensure the success of this project, ESL will partner with Aeroflex Lintek - a world-renowned developer of custom RF test equipment - to codevelop the MCMS. In this partnership, ESL will be responsible for design concept, requirements, proof-of-concept, and prototyping of hardware and software. Aeroflex Lintek will participate in the design effort and will be responsible for systems engineering and development of the final system. Aeroflex Lintek will perform this work for a small fraction of it's anticipated costs in return for the opportunity to develop, produce, and market a new generation RE test equipment based on technology developed from this project.