NeTS: Small: Collaborative Research: Towards Millimeter Wave Communications for Unmanned Aerial Vehicles

随着带宽饥渴型移动设备的激增、用户的密集部署以及物联网（IoT）技术的普及，宽带频谱需求近年来不断增加。使用毫米波（mmWave）频段被视为解决这一频谱紧张问题的主要方法，因为在这些频率上有大量许可和未许可的带宽可用，从而导致使用毫米波开发5G蜂窝和Wi-Fi的新标准。与此同时，商用无人机（UAV）技术最近取得了前所未有的进步，这使得它们被广泛应用于救灾、农业监测、农村地区的无线连接以及大型体育赛事的热点连接等领域。本项目拟进行的研究旨在从信道探测和表征开始，利用无线网络、通信理论、优化理论和软件定义无线电（sdr）的概念，系统地研究无人机毫米波通信的基础。从该项目收集的数据将通过5G毫米波信道建模联盟公开和传播。该项目将在一个国家感兴趣的新兴领域培养多个机构的研究生和本科生。任何毫米波通信的一个关键挑战是需要使用波束成形来克服路径损耗。在无人机上使用毫米波带来了额外的挑战和好处。这些挑战主要是由于无人机的电池寿命和载重能力有限，以及使用大带宽带来的好处：1)大带宽；2)能够实现3D波束成形，从而提高空间重用；3)利用无人机机动性进行无人机动态聚类和干扰管理。该项目的目标是通过独特的研究合作来解决这些基本挑战，重点是开发下一代分析和实验工具，用于设计、建模、优化和测试毫米波无人机网络。具体的研究领域将包括：(i)考虑到通道探测实验得出的实际传播特性的毫米波无人机的新型预编码器设计；（ii）平衡波束宽度和均衡器结构的毫米波无人机均衡器设计；（iii）毫米波无人机的多址设计：将重新研究毫米波无人机通信的码分和时分多址技术，以服务由同一发射机波束接入的用户；（iv）通过研究无人机作为飞行中继的使用，优化无人机在多跳无线回程中的位置。

With the proliferation of bandwidth hungry mobile devices, dense deployments of users, and the proliferation of Internet of Things (IoT) technologies, broadband spectrum needs have been continuously increasing in recent years. The use of the millimeter wave (mmWave) frequency bands is seen as a major way to address this spectrum crunch problem since large amounts of licensed and unlicensed bandwidths are available at these frequencies, leading to new standards being developed for 5G cellular and Wi-Fi using mmWave. In parallel, there have been unprecedented recent advances in commercial unmanned aerial vehicle (UAV) technologies, which has resulted in their adoption in a wide range of applications, such as disaster relief, agricultural monitoring, wireless connectivity in rural areas, and hotspot connectivity for major sporting events. The proposed research in this project aims to study the foundations of mmWave communications in UAVs in a systematic manner using notions from wireless networks, communication theory, optimization theory, and software defined radios (SDRs), starting from channel sounding and characterization. The data collected from this project will be made public and disseminated via the 5G Millimeter Wave Channel Modeling Alliance. The project will train both graduate students and undergraduate students across multiple institutions in an emerging area of national interest.A key challenge in any mmWave communication is that beamforming needs to be used in order to overcome the path loss. The use of mmWave on UAVs poses additional challenges and benefits. The challenges are primarily due to limited battery life and weight carrying capability of UAVs and the benefits accrue from the use of: 1) large bandwidth; 2) ability to implement 3D beamforming enabling improved spatial reuse; and 3) harnessing the UAV mobility to perform dynamic UAV clustering and interference management. The goal of this project is to address these fundamental challenges via a unique research collaboration focused on developing the next-generation of analytical and experimental tools for designing, modeling, optimizing, and testing mmWave UAV networks. Specific areas of study will include: (i) novel precoder designs for mmWave UAVs taking into account realistic propagation characteristics derived from channel sounding experiments; (ii) equalizer design for mmWave UAVs that trade-off beamwidth against equalizer structure; (iii) multiple access design for mmWave UAVs: code division and time division multiple access techniques will be revisited for mmWave UAV communications, for serving users that are accessed by the same transmitter beam; and (iv) optimal UAV placement for multi-hop wireless backhaul by investigating the use of UAVs as flying relays.