Ключевые технологии связи для поддержки систем управления движением гражданских беспилотных летательных аппаратов (обзор зарубежной литературы)

Not less than one hundred thousand Unmanned Aerial Vehicles (UAVs) are expected to perform flights simultaneously in Russia by 2035. The UAV fleet capacity triggers the development of the systems for informational support, operating control and management of UAV flights (Unmanned Aircraft System Traffic Management (UTM) systems) similar to that one already operating in manned aviation. The challenges arising in the sphere of civil aviation cannot be solved without wireless communication. The goals of this article are as follows: 1) familiarization of communication experts with the latest scientific developments of unmanned aerial technologies 2) description of the telecommunication-related problems of extensive systems of UAV control encountered by development engineers. In this article a schematic architecture and main functions of UTM systems are described as well as the examples of their implementation. Special emphasis is put on enhancing flight safety by means of a rational choice of communication technologies to manage conflicts (Conflict Management) known as "collision avoidance". The article analyzes the application of a wide range of wireless technologies ranging from Wi-Fi and Automatic Dependent Surveillance Broadcast (ADS-B) to 5G cellular networks as well as cell-free networks contributing to the development of 6G communication networks. As a result of the analysis, a list of promising research trends at the intersection of the fields of wireless communication and UAVs for civil application is made.Ожидается, что к 2035 году в Российском небе будут одновременно находиться не менее ста тысяч беспилотных летательных аппаратов (БЛА). Такая численность флота БЛА делает необходимым создание систем информационной поддержки, контроля и управления полетами БЛА (англ. Unmanned Aircraft System Traffic Management – UTM), подобных той, что уже существует для пилотной авиации. Проблемы, возникающие перед авиационным сообществом, не могут быть решены без помощи беспроводной связи. Целями данной статьи являются ознакомление специалистов связи с последними достижениями гражданской беспилотной авиации и описание проблем телекоммуникационного характера, стоящих перед разработчиками масштабных систем управления БЛА. Представлены архитектура и главные функции систем UTM, а также примеры их практической реализации. Особое внимание уделено повышению безопасности полетов путем рационального выбора технологий связи для осуществления управления конфликтными ситуациями (также известного как «избежание столкновений»). Проанализирована практичность применения широкого спектра беспроводных технологий: от Wi-Fi и автоматического зависимого наблюдения радиовещательного типа (АЗН-В) до сотовых сетей пятого поколения 5G, а также бессотовых сетей (англ. cell-free), являющихся кандидатами для создания сетей связи шестого поколения 6G. В результате проведенного анализа сформирован список перспективных направлений исследований на стыке областей беспроводной связи и гражданской беспилотной авиации

Aerial Coverage Analysis of Cellular Systems at LTE and mmWave Frequencies Using 3D City Models

Cellular connectivity for UAV systems is interesting because it promises coverage in beyond visual line of sight scenarios. Inter-cell interference has been shown to be the main limiting factor at high altitudes. Using a realistic 3D simulator model, with real base station locations, this study confirms that UAVs at high altitudes suffer from significant interference, resulting in a worse coverage compared to ground users. When replacing the existing base stations by mmWave cells, our results indicate that ground coverage is decreased to only 90%, while UAVs just above rooftop level have a coverage probability of 100%. However, UAVs at higher altitude still suffer from excessive interference. Beamforming has the potential to improve mmWave link budget and to decrease interference and is for this reason a promising technology for ensuring connectivity to aerial users

Aerial Coverage Analysis of Cellular Systems at LTE and mmWave Frequencies Using 3D City Models

Cellular connectivity for UAV systems is interesting because it promises coverage in beyond visual line of sight scenarios. Inter-cell interference has been shown to be the main limiting factor at high altitudes. Using a realistic 3D simulator model, with real base station locations, this study confirms that UAVs at high altitudes suffer from significant interference, resulting in a worse coverage compared to ground users. When replacing the existing base stations by mmWave cells, our results indicate that ground coverage is decreased to only 90%, while UAVs just above rooftop level have a coverage probability of 100%. However, UAVs at higher altitude still suffer from excessive interference. Beamforming has the potential to improve mmWave link budget and to decrease interference and is for this reason a promising technology for ensuring connectivity to aerial users.status: Published onlin

Performance evaluation of next generation wireless UAV relay with millimeter-wave in access and backhaul

Future wireless communication, particularly densified 5G networks, will bring numerous innovations to the telecommunication industry and will support 100-fold gain in throughput rates, 100-fold in capacity (for at least 100 billion devices), individual user data rate of up-to 10 Gb/s, extremely low latency and response times. In such a scenario, the use of Unmanned Aerial Vehicle (UAV) as a Base Station (gNB) becomes a viable option for providing 5G services, both on-demand and on a regular basis. Recent development of UAVs have made its deployment faster and reliable, resulting in a shift in its usage from traditional military to more commercial and corporate industries. On the other hand, due to the abundant availability of bandwidth in the millimeter-wave band (mmWave), there is an immense potential to utilize this band for next generation radio systems. In this case, smart integration of UAVs in 5G network provides immense potential, however, such network require efficient placement mechanism for providing blazingly fast wireless cellular network services. In this study, we analyze and describe the distinctive characteristics of mmWave propagation. The main goal is to investigate and evaluate the use of mmWave in Access and Back-haul communication links simultaneously for Amplify-and-Forward relays deployed on UAVs. We formulate the required mathematical framework for calculating the UE received power for direct path (gNB-UE) and relay path (gNB-UAV-UE) based on two cases; (i) Friis Transmission Equation and (ii) Log-Distance Path loss Model. We conduct simulations using ray-tracing simulator in different scenarios while comparing and verifying the simulation results vs mathematical equations. For the proposed system architecture, International Telecommunication Union (ITU) recommendation city model is used to calculate the probability for Line of Sight (LoS) and Non Line of Sight (NLoS) paths in different urban environments. Furthermore, we study and identify different parameters i.e., UAV location, and amplification factor to maximize the performance of an Amplify-and-Forward UAV based relay for providing enhanced coverage to the users. Similarly, the optimum UAV-gNB height is evaluated in different urban environments while providing coverage to the users via an Amplify-and-Forward relay. The study concludes with the Signal to Noise Ratio (SNR) analysis for the relay path compared with the direct path where we identify the constraints for effective relaying