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A Smooth-turn Mobility Model for Airborne Networks
In this article, I introduce a novel airborne network mobility model, called the Smooth Turn Mobility Model, that captures the correlation of acceleration for airborne vehicles across time and spatial coordinates. E?ective routing in airborne networks (ANs) relies on suitable mobility models that capture the random movement pattern of airborne vehicles. As airborne vehicles cannot make sharp turns as easily as ground vehicles do, the widely used mobility models for Mobile Ad Hoc Networks such as Random Waypoint and Random Direction models fail. Our model is realistic in capturing the tendency of airborne vehicles toward making straight trajectory and smooth turns with large radius, and whereas is simple enough for tractable connectivity analysis and routing design
Semi-Stochastic Aircraft Mobility Modelling for Aeronautical Networks: An Australian Case-Study Based on Real Flight Data
Terrestrial Internet access is gradually becoming the
norm across the globe. However, there is a growing demand for
Internet access of passenger airplanes. Hence, it is essential to
develop aeronautical networks above the clouds. Therefore the
conception of an aircraft mobility model is one of the prerequisite
for aeronautical network design and optimization. However, there
is a paucity of realistic aircraft mobility models capable of
generating large-scale flight data. To fill this knowledge-gap,
we develop a semi-stochastic aircraft mobility model based on
large-scale real historical Australian flights acquired both on
June 29th, 2018 and December 25th, 2018, which represent
the busiest day and the quietest day of 2018, respectively. The
semi-stochastic aircraft mobility model is capable of generating
an arbitrary number of flights, which can emulate the specific
features of aircraft mobility. The semi-stochastic aircraft mobility
model was then analysed and validated both by the physical
layer performance and network layer performance in the case
study of Australian aeronautical networks, demonstrating that it
is capable of reflecting the statistical characteristics of the real
historical flights
220102
In wireless powered sensor networks (WPSN), data of ground sensors can be collected or relayed by an unmanned aerial vehicle (UAV) while the battery of the ground sensor can be charged via wireless power transfer. A key challenge of resource allocation in UAV-aided WPSN is to prevent battery drainage and buffer overflow of the ground sensors in the presence of highly dynamic lossy airborne channels which can result in packet reception errors. Moreover, state and action spaces of the resource allocation problem are large, which is hardly explored online. To address the challenges, a new data-driven deep reinforcement learning framework, DDRL-RA, is proposed to train flight resource allocation online so that the data packet loss is minimized. Due to time-varying airborne channels, DDRL-RA firstly leverages long short-term memory (LSTM) with pre-collected offline datasets for channel randomness predictions. Then, Deep Deterministic Policy Gradient (DDPG) is studied to control the flight trajectory of the UAV, and schedule the ground sensor to transmit data and harvest energy. To evaluate the performance of DDRL-RA, a UAV-ground sensor testbed is built, where real-world datasets of channel gains are collected. DDRL-RA is implemented on Tensorflow, and numerical results show that DDRL-RA achieves 19\% lower packet loss than other learning-based frameworks.This work was partially supported by National Funds
through FCT/MCTES (Portuguese Foundation for Science and Technology), within the CISTER Research Unit
(UIDP/UIDB/04234/2020); also by national funds through
the FCT, under CMU Portugal partnership, within project
CMU/TIC/0022/2019 (CRUAV).
This work was in part supported by the Federal Ministry
of Education and Research (BMBF, Germany) as part of the
6G Research and Innovation Cluster 6G-RIC under Grant
16KISK020K.info:eu-repo/semantics/publishedVersio
Data Gathering and Dissemination over Flying Ad-hoc Networks in Smart Environments
The advent of the Internet of Things (IoT) has laid the foundations for new possibilities in our life. The ability to communicate with any electronic device has become a fascinating opportunity. Particularly interesting are UAVs (Unmanned Airborne Vehicles), autonomous or remotely controlled flying devices able to operate in many contexts thanks to their mobility, sensors, and communication capabilities. Recently, the use of UAVs has become an important asset in many critical and common scenarios; thereby, various research groups have started to consider UAVs’ potentiality applied on smart environments. UAVs can communicate with each other forming a Flying Ad-hoc Network (FANET), in order to provide complex services that requires the coordination of several UAVs; yet, this also generates challenging communication issues. This dissertation starts from this standpoint, firstly focusing on networking issues and potential solutions already present in the state-of-the-art. To this aim, the peculiar issues of routing in mobile, 3D shaped ad-hoc networks have been investigated through a set of simulations to compare different ad-hoc routing protocols and understand their limits. From this knowledge, our work takes into consideration the differences between classic MANETs and FANETs, highlighting the specific communication performance of UAVs and their specific mobility models. Based on these assumptions, we propose refinements and improvements of routing protocols, as well as their linkage with actual UAV-based applications to support smart services. Particular consideration is devoted to Delay/Disruption Tolerant Networks (DTNs), characterized by long packet delays and intermittent connectivity, a critical aspect when UAVs are involved. The goal is to leverage on context-aware strategies in order to design more efficient routing solutions. The outcome of this work includes the design and analysis of new routing protocols supporting efficient UAVs’ communication with heterogeneous smart objects in smart environments. Finally, we discuss about how the presence of UAV swarms may affect the perception of population, providing a critical analysis of how the consideration of these aspects could change a FANET communication infrastructure
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