A Survey of Air-to-Ground Propagation Channel Modeling for Unmanned Aerial Vehicles

In recent years, there has been a dramatic increase in the use of unmanned aerial vehicles (UAVs), particularly for small UAVs, due to their affordable prices, ease of availability, and ease of operability. Existing and future applications of UAVs include remote surveillance and monitoring, relief operations, package delivery, and communication backhaul infrastructure. Additionally, UAVs are envisioned as an important component of 5G wireless technology and beyond. The unique application scenarios for UAVs necessitate accurate air-to-ground (AG) propagation channel models for designing and evaluating UAV communication links for control/non-payload as well as payload data transmissions. These AG propagation models have not been investigated in detail when compared to terrestrial propagation models. In this paper, a comprehensive survey is provided on available AG channel measurement campaigns, large and small scale fading channel models, their limitations, and future research directions for UAV communication scenarios

C-Band Airport Surface Communications System Standards Development. Phase II Final Report. Volume 2: Test Bed Performance Evaluation and Final AeroMACS Recommendations

This report is provided as part of ITT s NASA Glenn Research Center Aerospace Communication Systems Technical Support (ACSTS) contract NNC05CA85C, Task 7: New ATM Requirements-Future Communications, C-Band and L-Band Communications Standard Development and was based on direction provided by FAA project-level agreements for New ATM Requirements-Future Communications. Task 7 included two subtasks. Subtask 7-1 addressed C-band (5091- to 5150-MHz) airport surface data communications standards development, systems engineering, test bed and prototype development, and tests and demonstrations to establish operational capability for the Aeronautical Mobile Airport Communications System (AeroMACS). Subtask 7-2 focused on systems engineering and development support of the L-band digital aeronautical communications system (L-DACS). Subtask 7-1 consisted of two phases. Phase I included development of AeroMACS concepts of use, requirements, architecture, and initial high-level safety risk assessment. Phase II builds on Phase I results and is presented in two volumes. Volume I is devoted to concepts of use, system requirements, and architecture, including AeroMACS design considerations. Volume II (this document) describes an AeroMACS prototype evaluation and presents final AeroMACS recommendations. This report also describes airport categorization and channelization methodologies. The purposes of the airport categorization task were (1) to facilitate initial AeroMACS architecture designs and enable budgetary projections by creating a set of airport categories based on common airport characteristics and design objectives, and (2) to offer high-level guidance to potential AeroMACS technology and policy development sponsors and service providers. A channelization plan methodology was developed because a common global methodology is needed to assure seamless interoperability among diverse AeroMACS services potentially supplied by multiple service providers

A study of RF-over-fibre based active RFID indoor location system

Location systems developed for indoor environments have attracted increasing interest, as a result of the rapidly growing location and navigation services provided by the Global Positioning System (GPS). Location information of people and objects can be used to cooperate with existing communication or database systems to provide abundant services to system operators and end users. For example, equipment tracking in hospitals ensure that location of the appropriate equipment can be provided simultaneously with necessary medical services; attendee tracking at conferences may encourage more efficient communications and networking; location of valuable assets in factories or warehouses aids logistics and protects these assets from theft. Since established global and terrestrial navigation systems cannot provide reliable location services in indoor environments, these demands are increasingly being met by wireless indoor location systems. A review of the existing systems reveals that the current systems are able to provide either an accurate location service with sophisticated system design at higher cost or a less accurate location service by means of integrated systems supplemented by existing facilities. This thesis presents a novel design of an indoor location system that is based on an RF-over-fibre backbone network, which is able to provide high location accuracy while the network infrastructure can be shared with multiple wireless systems. It is the first such demonstrator in this area. This research has been conducted by the author through a research project called The Intelligent Airport (TINA), which is the motivation for this research. The TINA project seeks to develop a new seamless wireless/wired ubiquitous infrastructure with high levels of computational capability to meet the application requirements of future airport environments. In the TINA system, multiple wireless services are provided through an integrated system supported by an RF-over-Fibre network, which transports RF signals through optical fibres. The active RFID indoor location unit is an essential part of the TINA system, which will facilitate the infrastructure to provide location-based services. The thesis describes the detailed design of the active RFID indoor location system proposed for the TINA project, and a few key issues discovered during trials of the demonstration system developed. The overall system design, including ranging technique, TDOA location finding algorithm, and hardware implementation, is presented in this thesis. Particular contributions also include a numerical algorithm for solving target location from TDOA measurement and a technique to determine the chirp linearity requirement. The field trial results of the system design demonstrate the principals and their location performance. The system has the potential to be extended to other scenarios where RF-over-fibre networks are employed and accurate location ability is desired

Wireless Channel Characterization in the 5 GHz Microwave Landing System Extension Band for Airport Surface Areas

In this project final report, entitled "Wireless Channel Characterization in the 5 GHz Microwave Landing System Extension Band for Airport Surface Areas," we provide a detailed description and model representation for the wireless channel in the airport surface environment in this band. In this executive summary, we review report contents, describe the achieved objectives and major findings, and highlight significant conclusions and recommendations

Survey of millimeter-wave propagation measurements and models in indoor environments

The millimeter-wave (mmWave) is expected to deliver a huge bandwidth to address the future demands for higher data rate transmissions. However, one of the major challenges in the mmWave band is the increase in signal loss as the operating frequency increases. This has attracted several research interests both from academia and the industry for indoor and outdoor mmWave operations. This paper focuses on the works that have been carried out in the study of the mmWave channel measurement in indoor environments. A survey of the measurement techniques, prominent path loss models, analysis of path loss and delay spread for mmWave in different indoor environments is presented. This covers the mmWave frequencies from 28 GHz to 100 GHz that have been considered in the last two decades. In addition, the possible future trends for the mmWave indoor propagation studies and measurements have been discussed. These include the critical indoor environment, the roles of artificial intelligence, channel characterization for indoor devices, reconfigurable intelligent surfaces, and mmWave for 6G systems. This survey can help engineers and researchers to plan, design, and optimize reliable 5G wireless indoor networks. It will also motivate the researchers and engineering communities towards finding a better outcome in the future trends of the mmWave indoor wireless network for 6G systems and beyond

Modelling of mmWave Propagation Channel for Off-body Communication Scenarios

Předkládaná disertační práce je zaměřena na \uv{Modelování propagačního kanálu pro off-body komunikaci v oblasti milimetrových vln}. Navzdory pokrokům v rámci bezdrátových sítí v přímé blízkosti člověka stále systémy 5. generace postrádají dostatečnou šířku pásma a dostatečně nízkou odezvu. To je způsobeno neefektivním využíváním rádiového spektra. Tento nedostatek je potřeba co nejdříve odstranit a právě z tohoto důvodu je hlavním cílem této práce navrhnout vylepšený model rádiového kanálů pro off-body komunikaci. Úkolem tohoto modelu je umožnit uživatelům efektivněji a přesněji simulovat propagaci signálu v rámci daného prostředí. Navržený model je dále optimalizován a ověřen vůči nejnovějším měřením, získaným z literatury. Nakonec je tento model implementován do simulačního nástroje NS-3, pomocí kterého je následně využit k simulaci množství scénářů. Hlavním výstupem této práce je ověřený model přenosového kanálu pro off-body komunikaci v rámci milimetrových vln, společně s jeho implementací do simulačního nástroje NS-3, díky čemuž je dostupný pro širokou veřejnost.This thesis addresses the \uv{Modeling of mmWave Propagation Channel for Off-body Communication Scenarios}. Despite the advancements in the body area wireless networks, the 5G systems are still struggling with not enough bandwidth and large latency due to inefficient utilization of radio spectrum. This issue calls for immediate action and therefore the main aim of this Ph.D. thesis is to propose a novel mmWave off-body channel, which will enable its users to more effectively simulate the signal propagation. The proposed model is further optimized and verified against state-of-the-art measurements from the literature. Finally, the developed model is implemented into the NS-3 simulator and utilized for plethora of simulation scenarios. The main output of this thesis is the verified developed model as well as the implementation inside the NS-3 simulator, which enables a wide society to use it.