Lightweight Simulation of Hybrid Aerial- and Ground-based Vehicular Communication Networks

Cooperating small-scale Unmanned Aerial Vehicles (UAVs) will open up new application fields within next-generation Intelligent Transportation Sytems (ITSs), e.g., airborne near field delivery. In order to allow the exploitation of the potentials of hybrid vehicular scenarios, reliable and efficient bidirectional communication has to be guaranteed in highly dynamic environments. For addressing these novel challenges, we present a lightweight framework for integrated simulation of aerial and ground-based vehicular networks. Mobility and communication are natively brought together using a shared codebase coupling approach, which catalyzes the development of novel context-aware optimization methods that exploit interdependencies between both domains. In a proof-of-concept evaluation, we analyze the exploitation of UAVs as local aerial sensors as well as aerial base stations. In addition, we compare the performance of Long Term Evolution (LTE) and Cellular Vehicle-to-Everything (C-V2X) for connecting the ground- and air-based vehicles

Analysis, Design and Empirical Validation of a Smart Campus Based on LoRaWAN

[Abstract] Internet of Things (IoT) applications for smart environments demand challenging requirements for wireless networks in terms of security, coverage, availability, power consumption, and scalability. The technologies employed so far to cope with IoT scenarios are not yet able to manage simultaneously all these demanding requirements, but recent solutions like Low-Power Wide Area Networks (LPWANs) have emerged as a promising alternative to provide low-cost and low-power consumption connectivity to nodes spread throughout a wide area. Specifically, the Long-Range Wide Area Network (LoRaWAN) standard is one of the most recent developments, receiving attention from both industry and academia. This work presents a comprehensive case study on the use of LoRaWAN under a realistic scenario within a smart city: a smart campus. Such a medium-scale scenario has been implemented through an in-house-developed 3D ray launching radio planning simulator that takes into consideration traffic lights, vehicles, people, buildings, urban fixtures, and vegetation. The developed tool is able to provide accurate radio propagation estimations within the smart campus scenario in terms of coverage, capacity, and energy efficiency of the network. These results are compared with an empirical validation in order to assess the operating conditions and the system accuracy. Moreover, the presented results provide some guidelines for IoT vendors, network operators, and city planners to investigate further deployments of LoRaWAN for other medium-scale smart city applicationsXunta de Galicia; ED431C 2016-045Xunta de Galicia; ED431G/01Agencia Estatal de Investigación; TEC2016-75067-C4-1-

Метод оцінки часу затримки в процесі потокового мовлення

Розглянута задача мінімізації затримки медіаконтенту при онлайн-трансляції. Об’єктом дослідження є медіасерверні платформи, що використовуються для організації онлайн-трансляцій медіаконтенту. Метою роботи є дослідження часу затримки при доставці медіаконтенту в процесі онлайн-трансляції. В процесі проведення експериментів встановлено, що найбільші витрати часу на доставку зумовлені процесом обробки потоку в медіасервері. Затримка в медіасервері виникає за рахунок перетворень сигналу. Проаналізовано найбільш поширені на ринку медіапослуг медасервери, які дозволяють організувати онлайнтрансляцію на регіональному рівні. Це Ant Media Server 1.7.2, MistServer 2.14.1, Nimble Streamer Server 3.5.4, Red5 1.1.1,Wowza Streaming Engine 4.7. Запропоновано методику оцінки часу затримки доставки медіаконтенту в мережах потокового мовлення. Розроблена методика надає змогу визначити як загальний час затримки, так і його складові на кожному з етапів доставки

Doppler Power Characteristics Obtained from Calibrated Channel State Information for Human Activity Recognition

Author's accepted manuscript.© 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.acceptedVersio