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

随着带宽需求旺盛的移动的设备的激增、用户的密集部署以及物联网（IoT）技术的激增，近年来宽带频谱需求一直在持续增长。毫米波（mmWave）频段的使用被视为解决这一频谱紧缩问题的主要方式，因为在这些频率上有大量的授权和非授权带宽可用，从而导致使用mmWave为5G蜂窝和Wi-Fi开发新标准。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重大体育赛事的热点连接等领域。该项目中的拟议研究旨在从信道探测和表征开始，使用无线网络，通信理论，优化理论和软件定义无线电（SDR）的概念，以系统的方式研究无人机中毫米波通信的基础。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。该项目将在国家感兴趣的新兴领域培训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UAV的电池寿命和重量承载能力有限，并且益处来自于使用：1）大带宽; 2）实现3D波束成形的能力，从而实现改进的空间重用;以及3）利用UAV移动性来执行动态UAV集群和干扰管理。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。研究的具体领域将包括：（i）毫米波无人机的新型预编码器设计，考虑到从信道探测实验中得出的实际传播特性;（ii）毫米波无人机的均衡器设计，权衡波束宽度与均衡器结构;（iii）毫米波无人机的多址设计：将重新考虑用于毫米波无人机通信的码分和时分多址技术，以便为通过相同发射波束接入的用户提供服务;以及（iv）通过调查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.