237 research outputs found
Enhancements of minimax access-point setup optimisation approach for IEEE 802.11 WLAN
As a flexible and cost-efficient internet access network, the IEEE 802.11 wireless local-area network (WLAN) has been broadly deployed around the world. Previously, to improve the IEEE 802.11n WLAN performance, we proposed the four-step minimax access-point (AP) setup optimisation approach: 1) link throughputs between the AP and hosts in the network field are measured manually; 2) the throughput estimation model is tuned using the measurement results; 3) the bottleneck host suffering the least throughput is estimated using this model; 4) the AP setup is optimised to maximise the throughput of the bottleneck host. Unfortunately, this approach has drawbacks: 1) a lot of manual throughput measurements are necessary to tune the model; 2) the shift of the AP location is not considered; 3) IEEE 802.11ac devices at 5 GHz are not evaluated, although they can offer faster transmissions. In this paper, we present the three enhancements: 1) the number of measurement points is reduced while keeping the model accuracy; 2) the coordinate of the AP setup is newly adopted as the optimisation parameter; 3) the AP device with IEEE 802.11ac at 5 GHz is considered with slight modifications. The effectiveness is confirmed by extensive experiments in three network fields
Implementation of improvements of the Wi-Fi network of the RTBF and implementation of a Wi-Fi network for an “intelligent” building
Este Trabajo de Fin de Grado se ha realizado dentro de la Radio Televisión Belga Francófona (RTBF)
en Bruselas. El objetivo de este proyecto es el diseño de una red Wi-Fi completamente confiable y de
alto rendimiento para una de sus localizaciones.
Para empezar, se completaron un estudio teórico y mediciones reales. La comparación entre el estudio
teórico y práctico no estaba concluyente por lo que las predicciones teóricas se han modificado para
corresponder a la realidad.
Finalmente, la RTBF está construyendo un nuevo edificio en 2022 para el cual un estudio predictivo
teórico se ha hecho para proporcionar una cantidad de puntos de accesos necesarios para una cobertura
completa.This End-of-Grade work have been done inside the Francophone Belgian Radio-Television (RTBF) in
Brussels. The goal of this Project is to design a fully reliable and performant Wi-Fi network for one of
their localization.
To begin with, a theorical study and real-life measurements were completed. The comparasion between
the theorical and practical study was not concluding so the theorical predictions have been changed to
correspond to reality.
Finally, the RTBF is constructing a new building in 2022 for which a theorical predictive study have
been done to provide the number of needed access points for a complete coverage.Grado en Ingeniería en Tecnologías de Telecomunicació
A Minimax Approach for Access Point Setup Optimization in IEEE 802.11n Wireless Networks
Recently, an IEEE 802.11n access point (AP) prevailed over the wireless local area network (WLAN) due to the high-speed data transmission using the multiple input multiple output (MIMO) technology. Unfortunately, the signal propagation from the 802.11n AP is not uniform in the circumferential and height directions because of the multiple antennas for MIMO. As a result, the data transmission speed between the AP and a host could be significantly affected by their relative setup conditions. In this paper, we propose a minimax approach for optimizing the 802.11n AP setup condition in terms of the angles and the height in an indoor environment using throughput measurements. First, we detect a bottleneck host that receives the weakest signal from the AP in the field using the throughput estimation model. To explore optimal values of parameters for this model, we adopt the versatile parameter optimization tool. Then, we optimize the AP setup by changing the angles and the height while measuring throughput. For evaluations, we verify the accuracy of the model using measurement results and confirm the throughput improvements for hosts in the field by our approach
Wi-Fi Long Distance Maritime Communications Data Analytics
Nowadays, wireless communications are becoming more and more important to the development of the society, not only in land, but also in the sea. When discussing about communications in maritime environments the scenario is different and harder, because of several factors, such as, the movement on the surface of the sea, the characteristics of the radio propagation and the possible intermittent obstruction that decrease the efficiency of signal propagation. Plenty of wireless communications solutions are already used in maritime environment, such as HF/VHF, which doesn't support high rates; satellite communications, which is an expensive technology and not affordable by most of users; and mobile communications (GSM, 3G and LTE), that only ensure connection near the coast. The main purpose of this dissertation is to contribute to the characterization of the propagation channel and the problems associated with the use of Wi-Fi technology for different frequencies in this kind of environment
Improving the Performance of Wireless LANs
This book quantifies the key factors of WLAN performance and describes methods for improvement. It provides theoretical background and empirical results for the optimum planning and deployment of indoor WLAN systems, explaining the fundamentals while supplying guidelines for design, modeling, and performance evaluation. It discusses environmental effects on WLAN systems, protocol redesign for routing and MAC, and traffic distribution; examines emerging and future network technologies; and includes radio propagation and site measurements, simulations for various network design scenarios, numerous illustrations, practical examples, and learning aids
Customizing Indoor Wireless Coverage via 3D-Fabricated Reflectors
Judicious control of indoor wireless coverage is crucial in built environments. It enhances signal reception, reduces harmful interference, and raises the barrier for malicious attackers. Existing methods are either costly, vulnerable to attacks, or hard to configure. We present a low-cost, secure, and easy-to-configure approach that uses an easily-accessible, 3D-fabricated reflector to customize wireless coverage. With input on coarse-grained environment setting and preferred coverage (e.g., areas with signals to be strengthened or weakened), the system computes an optimized reflector shape tailored to the given environment. The user simply 3D prints the reflector and places it around a Wi-Fi access point to realize the target coverage. We conduct experiments to examine the efficacy and limits of optimized reflectors in different indoor settings. Results show that optimized reflectors coexist with a variety of Wi-Fi APs and correctly weaken or enhance signals in target areas by up to 10 or 6 dB, resulting to throughput changes by up to -63.3% or 55.1%
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