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Neural Networks in Inertial Navigation Systems
Tejmlová, Lenka ; Ochodnický,, Ján (oponent) ; Masopust, Jiří (oponent) ; Šebesta, Jiří (vedoucí práce)
The dissertation is focused on inertial navigation systems and dead reckoning positioning. The issue in the problematics is that the dead reckoning systems and inertial navigation systems are inaccurate for medium-term and long-term application due to cumulative errors, assuming that the positioning is not supported by another external system. The dissertation shows possible approaches to the issue of more accurate positioning system based only on the inertial sensors. Basically we are talking about 9-DOF inertial measurement unit that allows sensing the global acceleration, rotation rate and magnetic field strength in three particular axes. The new approach brings artificial neural networks into data processing, where proper neural network is able to recognize the character of motion leading to improvement in positioning. The description of the proposed method includes an analytical procedure of its development and, if possible, the analytical performance assessment. Proposed artificial neural networks are modelled in MATLABTM and they are used for the determination of the state of the inertial unit. Due to this determination, the position of the inertial measurement unit is evaluated with higher accuracy. An application using Qt framework was developed to create an evaluation system with user interface for standard inertial measurement unit. The designed system based on artificial neural networks was verified by experiments using real sensor data.
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Advanced Methods for 3D Video Capturing and Evaluation
Kaller, Ondřej ; Klíma, Miloš (oponent) ; Masopust, Jiří (oponent) ; Kratochvíl, Tomáš (vedoucí práce)
The thesis focuses on advanced methods for 3D image and video capturing and evaluation. Based on a brief summary of spatial perception principles and the description of the state of the art in the areas of adaptive parallax and cameras configuration for traditional stereo pair shooting, especially up-to-date possibilities of depth map estimation are analyzed. Both active and passive methods are discussed; profilometry scanning is explained in more details. Qualitative parameters of two typical present systems of 3D displays are compared. The analysis is made for polarize discriminated and time multiplexed 3D displays technologies. Crosstalk between left and right images has been also measured. The core of the work consists in the design and testing of a new method of more precise estimation of the depth map in 3D videos. The novelty of the proposed approach lies in a sophisticated combination of partial results obtained by selected existing passive and active 3D scanning methods. The aim of the combination is to overcome drawbacks of individual methods and this way, to improve the accessible precision of the final depth map. The active method used is incoherent profilometry scanning which fails on surface discontinuities. As a passive method, a stereo pair matching is used. This method is currently the most widely applied method of depth map estimation in the field of 3D capturing and is available in various implementations. Finally, subjective tests of 3D video quality of experience (QoE) are dealt with. The most important outcome here is creation of the objective metric for the best estimation of subjective stereoscopic video quality.
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Optimalizace přístupu do CDMA sítí
Kejík, Petr ; Masopust, Jiří (oponent) ; Wieser, Vladimír (oponent) ; Hanus, Stanislav (vedoucí práce)
Cílem dizertační práce je optimalizace přístupu do sítí CDMA (Code Division Multiple Access). Práce se konkrétně zabývá algoritmy pro řízení přístupu do sítě pro systém UMTS (Universal Mobile Telecommunication System). V úvodní části je pozornost zaměřena na popis dosavadního vývoje dané problematiky a následně je provedena analýza řízení přístupu do sítě UMTS. V programu MATLAB byl vytvořen vlastní model systému UMTS, který umožňuje implementovat vybrané algoritmy přístupu do sítě. Pozornost byla zaměřena na algoritmy, které využívají činitel zatížení, fuzzy logiku a genetické algoritmy. Všechny algoritmy byly s pomocí vytvořeného simulačního programu vzájemně porovnány. Cílem práce je vytvořit vhodný simulační program, prozkoumat vlastnosti jednotlivých algoritmů a případně provést jejich optimalizaci.
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Speciální bezpečnostní systém
Náhlík, Ondřej ; Masopust, Jiří (oponent) ; Hanus, Stanislav (vedoucí práce)
V této diplomové práci je popsán návrh a realizace speciálního bezpečnostního systému na ochranu prostorů a majetku, který se dělí na 2 části, vysílací a přijímací. Vysílací část je tvořena zařízením Raspberry Pi Model B+, čidlem pohybu, webovou kamerou a USB LTE modemem Huawei E398. Přijímací část je pak tvořena počítačem s aplikací pro spojení s FTP serverem. V první části práce je popsán přenos dat v mobilních systémech, v další části jsou diskutovány možnosti řešení vysílací části. Ve třetí části je pak vybrána jedna z možností řešení vysílací části a jsou zde popsány programy vysílací části. V poslední části je popsána přijímací část a její aplikace.
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Millimeter Wave Band Wireless Channel Measurement Techniques in Automotive Applications
Vychodil, Josef ; Kovář, Pavel (oponent) ; Masopust, Jiří (oponent) ; Derbek, Vojtěch (vedoucí práce)
This doctoral thesis deals with the millimeter wave band wireless channel measurement techniques in automotive applications. After a brief introduction into the topic and the summary of the current channel measurement techniques, the goals --- the development and assembly of a measurement system, capable of capturing all of the millimeter wave band channel features and practical measurements with this system, are set. The next part is the core of the dissertation --- the developed channel sounder is presented and a detailed description of used methods, principles, hardware and data processing is given. A significant part of the thesis is dedicated to the mitigation of the unwanted effects caused by the non-linear components in the measurement chain. The last chapters show the results of practical measurements of various scenarios --- the intra-car channels, vehicle to vehicle channels as well as vehicle to infrastructure channels.
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Měření trajektorie malých cílů pomocí sítě CW radarů
Fuchs, Michal ; Masopust, Jiří (oponent) ; Kocur,, Dušan (oponent) ; Šebesta, Jiří (vedoucí práce)
Disertační práce se zabývá problematikou měření trajektorie cílů pomocí pole dopplerovských radarů. Pozornost je věnována měření trajektorií střel v balistickém tunelu a možnosti využití radarových senzorů s jedním směšováním v případě, kdy je striktně dán směr přiblížení cíle. Část disertační práce se věnuje rozboru a vývoji měřicího systému s akviziční jednotkou a systémovým kontrolérem. V teoretické části je prezentován vytvořený matematický model radarového senzorového pole a optimalizační systém určený pro ladění a hledání optimálních parametrů mapovacího systému. Práce se zabývá i možnostmi rekonstrukce trajektorií více objektů současně. Originální je použití gradientních metod s gaussovským předzpracováním k mapování a dále hledání kalibračních bodů nejbližšího přiblížení senzoru pomocí optimalizace V modelu.
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Models of Control Channels in the LTE System
Miloš, Jiří ; Wieser, Vladimír (oponent) ; Masopust, Jiří (oponent) ; Hanus, Stanislav (vedoucí práce)
The doctoral thesis is focused on a signal processing in the LTE physical control channels and performance analysis of control information transmission according to receiving conditions. The thesis is divided into two parts. The first part deals with simulation of the transmission of control information in baseband. The created simulators for uplink and downlink are presented. The simulations are performed for all possible system settings and various channel models. The MIMO influence on a quality of control information reception under fading channels is also presented. The second part of the thesis is focused on LTE utilization in shared channel ISM (2.4 GHz). The basic LTE application concept for ISM band is presented. This concept is fundamental to created simulation scenario. The chapter also presents the LTE and Wi-Fi coexistence simulator in 2.4 GHz ISM passband. The coexistence simulation are presented according to simulation scenario and the results are shown. The simulated coexistence analysis results are verified in laboratory environment. The comparison of the simulated and the measured coexistence analysis results is crucial for further optimization of the coexistence simulator. Recommendations for optimal and reliable operation of LTE are specified according to the simulated and the measured results. Recommendations should be useful to the reliable transmission of LTE control information in bad receiving conditions.
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Modely systému LTE
Navrátil, Petr ; Masopust, Jiří (oponent) ; Hanus, Stanislav (vedoucí práce)
Diplomová práce se zaměřuje na část nastávající mobilní sítě LTE. Konktrétně rozebírá fyzickou vrstvu LTE, která je zde rozdělena na 4 základní části: Fyzické kanály a modulace, Multiplexování a kanálová modulace, Procedury ve fyzické vrstvě a Měření na fyzické vrstvě. Každou část popisuje příslušná norma vydaná společností 3GPP [1], u které jsou uvedeny i aktuální specifikace, ze kterých je tvořena tato práce. Pro pochopení problematiky se předpokládá základní znalost systémů OFDM, který systém LTE využívá. V další části se práce věnuje tvorbě matematického modelu fyzické vrstvy vytvořené v programu Matlab. Tento model je zaměřen na stanovení chybovosti vzniklé přenosem dat přes konkrétní rádiové prostředí.
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Numerical synthesis of filtering antennas
Kufa, Martin ; Mazánek, Miloš (oponent) ; Masopust, Jiří (oponent) ; Raida, Zbyněk (vedoucí práce)
The dissertation thesis is focused on a complete design methodology of a three and four-element patch antenna arrays which are without any filtering parts and yet behave like a filtering antenna (filtenna). This design combines filter and antenna approaches and includes shaping the frequency response of the reflection coefficient and the modelling of the frequency response of the normalized realized gain. The frequency response of the main lobe direction is controlled as well. In order to control the shape of these responses, a set of gi coefficients for designing the filtering antenna array are obtained. The design methodology was verified on the three-element and four-element filtennas over the frequency range from 4.8 GHz to 6.8 GHz; for fractional bandwidth from 7 % to 14 % and for level of the reflection coefficient from –10 dB to –20 dB. The whole design methodology was supported by manufacturing and measuring six test cases of the filtering antenna array with different configurations. Simulated and measured results show a good agreement in all cases.
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Intra- and Out-of-Vehicle Channel Measurements and Modeling
Kukolev, Pavel ; Masopust, Jiří (oponent) ; Wieser, Vladimír (oponent) ; Prokeš, Aleš (vedoucí práce)
The dissertation is focused on channel measurements and modeling for vehicle-to-X communication and on localization. In order to realize an integrated intelligent transportation system (ITS), it is important to estimate channel features for intra-vehicle and out-of-vehicle scenarios. For this propose the following activities are carried out: simulation of the 802.11p PHY; comparison with 802.11a; channel measurements for different scenarios based on the 802.11p and ultra-wideband (UWB); creating channel models for 802.11p and UWB; UWB measurements to assess performance of localization. The vehicle-to-X communication is supposed on the IEEE 802.11p standard. The dissertation presents the differences between IEEE 802.11a and IEEE 802.11p physical layer standards through the simulation results of the transmission over a HIPERPLAN/2 channel. Further, the simulation of the 802.11p signal transmission over ITU-R M.1225 channel, which includes pedestrian and vehicle models with different relative delays and average power, is presented. The influence of the channel on the signal is analyzed using MATLAB simulation in terms of bit error rate (BER). The dissertation reports vehicular channel measurements in the frequency band of 5.8 GHz for IEEE 802.11p standard and for UWB (3-11 GHz). Experiments for both intra-vehicle and out-of-vehicle environments are carried out. It was observed that the large-scale variations (LSVs) of the power delay profiles (PDPs) can be best approximated through a two-term exponential decay model for the 802.11p protocol, in contrast to the Saleh-Valenzuela (S-V) model which is suitable for UWB systems. For each measurement, the LSV trend was used to construct the respective channel impulse response (CIR). Next, the CIR is used in 802.11p simulation to evaluate the BER performance, following a Rician model. The results of the BER simulation shows the suitability of the protocol for in-car as well as out-of-car wireless applications. The simulation for out-of-car parameters indicate that the error performances do not vary much and it is possible to determine an average BER curve for the whole set of data. The randomness in UWB channel for small positional variations around a car, parked in an underground garage, is reported. The path loss (PL) is found to be monotonically increasing with distance but varies randomly with angle and height and thereby renders signal strength based ranging inaccurate for such scenarios. On the other hand, arrival time of the first ray can be used for reliable estimation of distance, independent on transmitter angle or height. The number of clusters in the PDP is reduced with distance but the nature of the profile remains fairly consistent with angle. The S-V model parameters also vary with distance and height but their average values are close to the IEEE 802.15.3 recommended channel model. For localization applications the distance between the antennas is calculated exploiting the linear dependence of distance on delay from PDP. The coordinates of a transmitting antenna are found with the help of two receiving antennas following a two-dimensional (2-D) time-of-arrival (TOA) based localization technique. A comparison of the calculated coordinates with the original ones exhibits an error of less than 6% which supports the suitability of the proposed approach for localization of the cars.
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