MRI: Acquisition of a 4-40 GHz VNA-Based Material and Channel Sounder for Wireless Communications and Radar Research

当前的无线系统，如WiFi和4G蜂窝网络，在低于6ghz的微波频率下运行。由于这种有限频谱的传输速度通常只有每秒10兆比特，因此5G的一个重要目标是开发每秒千兆比特的无线网络，提供更类似于有线网络的速度。最近，密集的研究表明，利用60千兆赫及以上的毫米波频段，千兆无线是可能的，但在这些频率上，障碍物造成的信号损失是令人望而却步的，而且半导体设备的成本目前很高。该项目提出了一种通道测量仪器，可以详细研究10-40 GHz频率范围（Ku-Ka频段），可能为千兆无线提供所需的带宽增加，但没有60 GHz以上的一些缺点。迄今为止，Ku-Ka波段受到的关注很少，而且在Ku-Ka常见建筑材料存在的情况下，信号传输的详细信息也没有公开提供。使用拟议的仪器进行的测量将纠正这种情况，从而形成一个开放的Ku-Ka波段建筑材料数据库。该数据库预计将对工业和学术界在10-40 GHz范围内运行的无线网络的评估和规划具有巨大价值，支持实用千兆无线网络和设备的开发。该仪器还将支持多天线通信、雷达和遥感方面的新实验。该仪器将广泛用于本科教学和研究，每年约有80名学生接触到最先进的设备和技术。在利哈伊山谷内的其他机构免费提供仪器将为新的合作研究提供机会。技术：为了支持5G网络及以后的Ku-Ka频段的详细表征，该项目建议采购一个由高动态范围矢量网络分析仪组成的4-40 GHz信道测深仪，其中两个端口可以光学远程到150米。此外，端口上的交换机每个端口最多可容纳8个天线，用于多输入多输出（MIMO）传播研究。该仪器能够为Ku-Ka频段开发建筑材料特性的综合数据库，例如介电常数、电导率、粗糙表面和随机体积参数，这对于5G及以后的无线网络非常重要。在校园内外的几个地点对建筑材料进行现场测量，将使数据库不仅包括平均值，还包括性能的统计变化。在详细的光线追踪模拟中使用提取的属性将揭示哪些频带最适合替代当前使用的无线频带，并将允许量化波束成形，MIMO传输和大规模MIMO的真正必要性和/或好处。该系统支持多达四个节点的8x8通道直接MIMO测量的能力将允许评估提取材料属性的潜在准确性。考虑到该系统的灵活性，在MIMO通信、MIMO雷达和无人机系统（UAS）传感方面的新实验将有助于推进这些领域的最新技术。

AbstractNontechnicalCurrent wireless systems, such as WiFi and 4G cellular networks, operate at microwave frequencies below 6 GHz. Since transfer speeds in this limited spectrum are typically only 10s of megabits-per-second, an important aim of 5G is the development of gigabit-per-second wireless networks providing speeds more similar to wired networks. Recently, intense research has demonstrated that gigabit wireless is possible by exploiting millimeter-wave bands at 60 GHz and above, yet at those frequencies signal losses from obstacles are prohibitive and the cost of semiconductor devices is currently high. This project proposes acquisition of a channel measurement instrument allowing detailed study of the 10-40 GHz frequency range (the Ku-Ka bands), likely providing the needed bandwidth increase for gigabit wireless, but without some drawbacks present above 60 GHz. To date, the Ku-Ka bands have received little attention, and detailed information on signal transmission in the presence of common building materials in Ku-Ka is not openly available. Measurements performed with the proposed instrumentation will correct this situation, resulting in an open database of building materials for the Ku-Ka bands. This database is expected to have immense value to industry and academia in the assessment and planning of wireless networks operating in the 10-40 GHz range, supporting the development of practical gigabit wireless networks and devices. The instrument will also support new experiments in multiple-antenna communications, radar, and remote sensing. The instrument will find extensive use in undergraduate teaching and research, exposing approximately 80 students per year to state-of-the-art equipment and techniques. Availability of the instrumentation to other institutions within the Lehigh Valley at no cost will provide opportunities for new collaborative research.TechnicalTo support detailed characterization of the Ku-Ka bands for 5G networks and beyond, this project proposes the acquisition of a 4-40 GHz channel sounder consisting of a high dynamic range vector network analyzer, where two of the ports may be optically remoted up to 150m. Further, switches at the ports accommodate up to 8 antennas per port for multiple-input multiple-output (MIMO) propagation studies. This instrumentation enables a comprehensive database of building material properties, such as permittivity, conductivity, and rough surface and random volume parameters, to be developed for the Ku-Ka bands, which is expected to be extremely important for wireless networks in 5G and beyond. In-situ measurement of building materials at several sites on and off campus will allow the database to include not only mean values, but also statistical variation of properties. Employing the extracted properties in detailed ray-tracing simulations will reveal which bands are most suitable as a replacement for currently used wireless bands, and will allow the true necessity and/or benefits of beamforming, MIMO transmission, and massive MIMO to be quantified. The capability of the system to support direct MIMO measurement of 8x8 channels at up to four nodes will allow the underlying accuracy of the extracted material properties to be assessed. Given the flexibility of the system, new experimentation in MIMO communications, MIMO radar, and sensing from unmanned aircraft systems (UAS) will help advance the state-of-the-art in those areas.