13,186 research outputs found
Coverage, capacity and interference analysis for an aerial base station in different environments
With the advancing 5G technology of base stations mounted on aerial platforms, such as unmanned aerial vehicles, the issue of coverage area, capacity and inter-cell interference is assuming higher importance for the cellular networks. In this paper, we follow a deterministic approach to analyze these problems using the data obtained from a commercial software for wireless electromagnetic wave propagation. We analyze the above mentioned parameters by varying the threshold of the received power. Also, we find an optimal altitude and power consumption model for an aerial base station. Simulations were carried out in three generalized environments, Suburban, Urban and Urban High Rise, developed according to ITU-R parameters. To derive these results we used an air-to-ground channel model obtained from the analysis of simulation data
Drone Small Cells in the Clouds: Design, Deployment and Performance Analysis
The use of drone small cells (DSCs) which are aerial wireless base stations
that can be mounted on flying devices such as unmanned aerial vehicles (UAVs),
is emerging as an effective technique for providing wireless services to ground
users in a variety of scenarios. The efficient deployment of such DSCs while
optimizing the covered area is one of the key design challenges. In this paper,
considering the low altitude platform (LAP), the downlink coverage performance
of DSCs is investigated. The optimal DSC altitude which leads to a maximum
ground coverage and minimum required transmit power for a single DSC is
derived. Furthermore, the problem of providing a maximum coverage for a certain
geographical area using two DSCs is investigated in two scenarios; interference
free and full interference between DSCs. The impact of the distance between
DSCs on the coverage area is studied and the optimal distance between DSCs
resulting in maximum coverage is derived. Numerical results verify our
analytical results on the existence of optimal DSCs altitude/separation
distance and provide insights on the optimal deployment of DSCs to supplement
wireless network coverage
Performance Analysis of Micro Unmanned Airborne Communication Relays for Cellular Networks
This paper analyses the potential of utilising small unmanned-aerial-vehicles
(SUAV) as wireless relays for assisting cellular network performance. Whilst
high altitude wireless relays have been investigated over the past 2 decades,
the new class of low cost SUAVs offers new possibilities for addressing local
traffic imbalances and providing emergency coverage.We present field-test
results from an SUAV test-bed in both urban and rural environments. The results
show that trough-to-peak throughput improvements can be achieved for users in
poor coverage zones. Furthermore, the paper reinforces the experimental study
with large-scale network analysis using both stochastic geometry and multi-cell
simulation results.Comment: conferenc
Unmanned Aerial Vehicle with Underlaid Device-to-Device Communications: Performance and Tradeoffs
In this paper, the deployment of an unmanned aerial vehicle (UAV) as a flying
base station used to provide on the fly wireless communications to a given
geographical area is analyzed. In particular, the co-existence between the UAV,
that is transmitting data in the downlink, and an underlaid device-todevice
(D2D) communication network is considered. For this model, a tractable
analytical framework for the coverage and rate analysis is derived. Two
scenarios are considered: a static UAV and a mobile UAV. In the first scenario,
the average coverage probability and the system sum-rate for the users in the
area are derived as a function of the UAV altitude and the number of D2D users.
In the second scenario, using the disk covering problem, the minimum number of
stop points that the UAV needs to visit in order to completely cover the area
is computed. Furthermore, considering multiple retransmissions for the UAV and
D2D users, the overall outage probability of the D2D users is derived.
Simulation and analytical results show that, depending on the density of D2D
users, optimal values for the UAV altitude exist for which the system sum-rate
and the coverage probability are maximized. Moreover, our results also show
that, by enabling the UAV to intelligently move over the target area, the total
required transmit power of UAV while covering the entire area, is minimized.
Finally, in order to provide a full coverage for the area of interest, the
tradeoff between the coverage and delay, in terms of the number of stop points,
is discussed.Comment: accepted in the IEEE Transactions on Wireless Communication
Hybrid Satellite-Terrestrial Communication Networks for the Maritime Internet of Things: Key Technologies, Opportunities, and Challenges
With the rapid development of marine activities, there has been an increasing
number of maritime mobile terminals, as well as a growing demand for high-speed
and ultra-reliable maritime communications to keep them connected.
Traditionally, the maritime Internet of Things (IoT) is enabled by maritime
satellites. However, satellites are seriously restricted by their high latency
and relatively low data rate. As an alternative, shore & island-based base
stations (BSs) can be built to extend the coverage of terrestrial networks
using fourth-generation (4G), fifth-generation (5G), and beyond 5G services.
Unmanned aerial vehicles can also be exploited to serve as aerial maritime BSs.
Despite of all these approaches, there are still open issues for an efficient
maritime communication network (MCN). For example, due to the complicated
electromagnetic propagation environment, the limited geometrically available BS
sites, and rigorous service demands from mission-critical applications,
conventional communication and networking theories and methods should be
tailored for maritime scenarios. Towards this end, we provide a survey on the
demand for maritime communications, the state-of-the-art MCNs, and key
technologies for enhancing transmission efficiency, extending network coverage,
and provisioning maritime-specific services. Future challenges in developing an
environment-aware, service-driven, and integrated satellite-air-ground MCN to
be smart enough to utilize external auxiliary information, e.g., sea state and
atmosphere conditions, are also discussed
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
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