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Lokalizace počítačových zařízení ve Wifi sítích / Device Location in Wireless NetworkSzabó, Peter January 2015 (has links)
This thesis deals with the issue of locating devices in wireless networks. It takes existing solutions as example and extends them using additional approaches. This thesis designs and describes the implementation of a prototype of a new proprietary indoor localization system used for locating devices within a WiFi network. In the final part of the thesis the testing of this system is described and its results are analysed and compared with another localization systems based on similar technologies.
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Model adaptivního streamování videa přes HTTP / Model of HTTP adaptive video streamingKasianenko, Dmytro January 2016 (has links)
Key tasks of this work are to create the simulation of a wireless network in ns-3 and to stream a video over this network by using MPEG-DASH technology. It describes the tools and methods how to encode a video according to MPEG-DASH. It is explained what is needed to run video server, which uses MPEG-DASH technology to stream videos. Then, it is described how a simulation of wired and wireless WiFi and LTE networks is created. The simulation starts a server and shows how it works, how many nodes can be used and chooses suitable segment duration.
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Komunikace mezi systémem Android a platformou Arduino / Communication between the Android OS and Arduino PlatformMychko, Maksim January 2015 (has links)
This thesis deals with creating a library for the Android OS which enables efficient wireless communication with platform Arduino. The target is to create an application for Android OS, using a created library that allows you to capture data from various sensors and control effectors. The work describes basic wireless interfaces for Android OS and Arduino platform. The main benefits and drawbacks functions are also introduced. The comparison of current consumption for modules HM-10 and DIGI S1 has been carried out as well. Possibility of data acquisition and effector controlling exercises have been tested and verified.
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A Study of the Next WLAN Standard IEEE 802.11ac Physical LayerAl-Ghazu, Nader January 2013 (has links)
This thesis studies the Physical Layer (PHY) of the new IEEE 802.11acWireless Local Access Network (WLAN) standard. The 11ac is built basedon the 11n successful standard. The standard is expected to be completedby the end of 2013. And it promises a Very High Throughput (VHT),and robust communication. In order to achieve that, the 11ac uses morebandwidth, it employs higher numbers of Multiple-Input Multiple-Output(MIMO) spatial streams, and higher orders of modulations. The 11ac PHYframe structure is studied in details. The transmitter and receiver blocks areexplained and implemented by MATLAB. Bit Error Rate (BER) and ErrorVector Magnitude (EVM) simulations of the PHY were run. The effectof different Modulation and Coding Scheme (MCS), and bandwidths werestudied. The performance of MIMO and Space-Time Block Coding (STBC)was investigated. The simulation results shows how the 11ac benefits fromthe new employed features. The created MATLAB simulation program canbe used for further tests and research.
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Broadband Wireless Access in Disaster Emergency ResponseBai, Xin January 2006 (has links)
The “WLAN in Disaster Emergency Response” (WIDER) project has developed and implemented an emergency communication system. It provides network and communication services to relief organizations. In order to guarantee the stable and efficient connectivity with a high quality of service (QoS) for the end user, and to make the WIDER system more adaptive to the disaster area, the IEEE 802.16 specification based broadband wireless access solution is adopted. This thesis work aims at evaluating and testing the WIDER system integrated with WiMAX. By learning and analyzing the technology, the benefits and perspective for WIDER using WiMAX are described. A WiMAX solution was configured and integrated into the WIDER system. A series of tests and measurements provide us the performance of the WiMAX solution in throughput, QoS, and reality. The tests helped us to learn and verify the improvements for WIDER due to WiMAX. / “WLAN in Disaster Emergency Response” (WIDER) projektet har utvecklat och implementerat ett kommunikationssystem för katastrof situationer. Systemet tillhandahåller nätverk- och kommunikationstjänster för hjälporganisationer. För att garantera en stabil och effektiv anslutning med hög Quality of Service för användarna samt göra WIDER systemet mer anpassbart för katastrofområden, kommer Broadband wireless access som är baserade på IEEE 802.16 specifikationen att användas. Det här examensarbetet har som målsättning att utvärdera och testa WIDER med WiMax tekniken, vi beskriver olika fördelar och synvinklar med att använda WiMax genom att lära oss och analysera tekniken. En WiMax lösning konfigurerades och integrerades i WIDER systemet. En rad tester och mätningar visar WiMax-lösningens prestanda i form av throughput, Quality of Service och realitet. Testerna lärde oss och hjälpte oss att verifiera förbättringarna i WIDER i och med användningen av WiMax.
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WiFi fingerprinting based indoor localization with autonomous survey and machine learningHoang, Minh Tu 01 September 2020 (has links)
The demand for accurate localization under indoor environments has increased dramatically in recent years. To be cost-effective, most of the localization solutions are based on the WiFi signals, utilizing the pervasive deployment of WiFi infrastructure and availability of the WiFi enabled mobile devices. In this thesis, we develop completed indoor localization solutions based on WiFi fingerprinting and machine learning approaches with two types of WiFi fingerprints including received signal strength indicator (RSSI) and channel state information (CSI).
Starting from the low complexity algorithm, we propose a soft range limited K nearest neighbours (SRL-KNN) to address spatial ambiguity and the fluctuation of WiFi signals. SRL-KNN exploits RSSI and scales the fingerprint distance by a range factor related to the physical distance between the user’s previous position and the reference location in the database. Although utilizing the prior locations, SRL-KNN does not require knowledge of the exact moving speed and direction of the user. Besides, the idea of the soft range limiting factor can be applied to all of the existed probabilistic methods, i.e., parametric and nonparametric methods, to improve their performances. A semi-sequential short term memory step is proposed to add to the existed probabilistic methods to reduce their spatial ambiguity of fingerprints and boost significantly their localization accuracy.
In the following research phase, instead of locating user's position one at a time as in the cases of conventional algorithms, our recurrent neuron networks (RNNs) solution aims at trajectory positioning and takes into account of the relation among RSSI measurements in a trajectory. The results using different types of RNN including vanilla RNN, long short-term memory (LSTM), gated recurrent unit (GRU) and bidirectional LSTM (BiLSTM) are presented.
Next, the problem of localization using only one single router is analysed. CSI information will be adopted along with RSSI to enhance the localization accuracy. Each of the reference point (RP) is presented by a group of CSI measurements from several WiFi subcarriers which we call CSI images. The combination of convolutional neural network (CNN) and LSTM model is proposed. CNN extracts the useful information from several CSI values (CSI images), and then LSTM will exploit this information in sequential timesteps to determine the user's location.
Finally, a fully practical passive indoor localization is proposed. Most of the conventional methods rely on the collected WiFi signal on the mobile devices (active information), which requires a dedicated software to be installed. Different from them, we leverage the received data of the routers (passive information) to locate the position of the user. The localization accuracy is investigated through experiments with several phones, e.g., Nexus 5, Samsung, Iphone and HTC, in hundreds of testing locations. The experimental results demonstrate that our proposed localization scheme achieves an average localization error of around 1.5 m when the phone is in idle mode, and approximately 1 m when it actively transmits data. / Graduate
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Metody autentizace napojení k WiFi síti / Methods of Authentication to WiFi NetworkValašek, Filip Unknown Date (has links)
This diploma thesis deals with authentication using RADIUS protocol and authentication methods in accordance with standard IEEE 802.1X. At the beginning there are shortly characteristics of chosen authentication methods, such as CHAP, PAP and some EAP types. Document includes summary of RADIUS protocols implementations, especially the FreeRADIUS server. Our goal is to implement a management tool to adminitrate FreeRADIUS server.
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Mapování bezdrátových technologií v terénu s využitím GPS / Wireless Networks Outdoor Mapping with GPS LocalisationKabátek, Petr January 2007 (has links)
This thesis deals with the monitoring of wireless nets in terrain. The author will be browsing terrain and there will be extracted some information about accessible wireless nets. For parameters of wireless nets we consider for example the name of wireless net, signal strength, type of security etc. These parameters (of wireless nets and position) are going to be recorded and saved into the database. Using this database it will be possible to perform some further operations like generation maps of wireless networks or detection positions of access points, etc..
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Fine-Grained Hand Pose Estimation System based on Channel State InformationYao, Weijie January 2020 (has links)
No description available.
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Ontology based framework for Tactile Internet and Digital Twin ApplicationsAdhami, Hikmat 09 August 2022 (has links)
In the era of Industry 4 and Digital Twin – DT- (integrating Audio-Video, Virtual Reality,
Augmented Reality and Haptics - from the Greek word Haptikos meaning "able to touch") and the Tactile Internet (TI), it becomes obvious that telecom stakeholders need different networks requirements to provision high quality services with respect to the new standards. In reality, this era is proposed as TI, and it will achieve a true paradigm shift from content delivery to skill-set delivery network types, thanks to recent technical breakthroughs. It will build a new internet structure with improved capabilities; but it will be difficult to meet the technical needs of the TI with current fourth generation (4G) mobile communication systems. As a result, 5G mobile
communication systems will be used at the wireless edge and as a key enabler for TI due to its automated core network functionalities.
Because of the COVID-19 outbreak, most daily activities such as employment, research, and education are now conducted online rather than in person. As a result, internet traffic has risen dramatically. Nowadays, Tactile Internet is in its infancy deployment phase worldwide. For this reason, and because of the growing need of its applications, the feasibility of these applications on the existing and deployed networks infrastructures, especially in the growing countries, is thought
to be very hard, even quasi-impossible. Since 5G is not reaching yet its convergence stage (i.e. it is not deployed everywhere) and there is a huge stress on mobile communications given that the world is still facing the COVID-19 Pandemic, and since all the activities are taking place online, we propose design and implement a QoS framework to facilitate the feasibility and the applicability of the TI systems, where no 5G infrastructure is deployed. This framework will predict the most suitable network type to be deployed for certain given TI applications with certain given KPIs (Key Performance Indicators). Also, this framework is scalable, in such it gives an idea of even the future Next Generation Mobile Networks types (NGMN, if necessary).
“To deal” with TI applications, means “to deal” with Haptics added to Audio and Video streams. Therefore, performance evaluation for haptic networks is required. And since there are different types of haptic networks, so interoperability is needed. Consequently, a standardization form is necessary for that purpose, to annotate and describe the haptic network. The first idea that flashes in mind, is the use of Ontologies. In these latters, we can add intelligent rules to infer additional data and predict resource requirements in order to achieve better performance. Many works in the research rely on Artificial Intelligence approaches to tackle the above-mentioned
standardization, but very few depend on ontologies, and without futuristic outcomes, especially for the optimization problem. We mean by optimization, the optimal types, methods and rules that are able to accommodate the applicability of the TI systems (here come the applications KPIs) in an acceptable environment or infrastructure (here come the networking KPIs), and even-more, to infer the most optimal network type.
To help manufacturing companies take full advantage of the TI, we propose to develop new methods and tools (ontologies) to intelligently handle the TI, DT (Digital Twin) and IoT (Internet of Things) sensor data and process data at the edge of the network and deliver faster insights. The outcomes of these ontologies, have been validated through two conducted case studies, where we simulated, in the first, TI traffic over Wi-Fi, WiMAX and UMTS (3G) infrastructures; While in the second we used 4G (LTE-A), along with SDN (Software Defined Networking) integrated to MEC (Mobile Edge Computing) as networking backbone. The results, in terms of QoS KPIs performance evaluation, present high relevance to our proposed Ontology outcomes.
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