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Self-adhesive antennas for on-body communication
Punar, Jan ; Fiala, Pavel (referee) ; Raida, Zbyněk (advisor)
This project is focused on planar antennas for on body communication. Project follows the concept of a self-adhesive antenna, which was published in [1]. The included report contains simulation results of the designed antenna, and compares them with results given in [1]. It describes the redesign of the antenna to the operation frequency 5.8 GHz for substrate Arlon 25N followed by subsequent conversion to the thin substrate FR4. The thesis also deals with antennas not only for on body communication but also for communication between the human body and the remote unit. Finally, the work contains measurement results of the reference antenna on the Arlon 25N substrate.
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Low Profile Integrated Antenna for GPS and DRSC
Kolb, Lukáš ; Kovács, Peter (referee) ; Raida, Zbyněk (advisor)
In the project, planar antennas for receiving satellite GPS signals and DSRC ones were investigated and mutually combined. The combined antenna was designed for the substrate ARLON, CuClad 217 LX, was modeled and optimized in the program ANSOFT Designer. Attention was turned to the proper impedance matching, directivity properties and polarization properties. The designed antenna was built and their properties were experimentally verified.
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Small-size active integrated antenna
Nunvář, Rostislav ; Pokorný, Michal (referee) ; Raida, Zbyněk (advisor)
Bachelor’s thesis deals with basic types of planar antennas, with the design and simulation in the program ANSOFT Designer. The project is focused on the completion of a planar antenna by an active element (a transistor). The transistor can be integrated into planar structure by the N-Port function of Ansoft Designer. Finally, advantages and disadvantages of passive and active planar antennas are described.
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Miniature antennas for mobile communications
Kounek, Milan ; Láčík, Jaroslav (referee) ; Pokorný, Michal (advisor)
This bachelor thesis deals with downsizing techniques of planar antennas, while keeping important parameter for usage in mobile communications. In software IE3D there was designed antenna, working in ISM 2,4GHz band, which was downsized by methods described in this thesis. A group of antennas was created, 2 antennas were chosen, produced and measured. Results of measuring were compared with simulation and differences were evaluated.
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Reflect-array with electronic beam steering
Bílek, Ondřej ; Závodný,, Vadim (referee) ; Raida, Zbyněk (advisor)
The diploma thesis is aimed to design, optimize, produce and subsequently measure the properties of the reflector with the electronic steering direction for the frequency of the 24,125 GHz band ISM. The problem chosen is solved by a group of voltage-controlled varicaps. The reflector consists of a matrix of two rows, each containing 3 cells. The reflector was designed by full-wave software CST Microwave Studio 2015.
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User influence on miniature antennas in mobile applications
Vehovský, Radek ; Polívka,, Milan (referee) ; Pokorný, Michal (advisor)
This master’s thesis deals with user influence on miniature antennas in mobile application. Electrically small antennas including fundamental performance properties and limitations are introduced in the theoretical section of this thesis. This section also deals with microstrip antennas and their common types. The accent is on PIFA antennas, their typical constructions and methods of miniaturization. In the practical section, dual-band PIFA antenna for operation at frequencies of systems GSM900 and GSM1800 is designed with the assistance of electromagnetic field simulator CST Microwave Studio. On this type of antenna, the user influence on impedance matching and radiation pattern in data mode (the user is typing message or browsing with the phone) is investigated. For this purpose the hand phantom, corresponding to author’s right hand, was made from agar based material. For typical position of human hand is designed matching network, which eliminate the user influence and ensure correct function of antenna.
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Automotive antenna for mobile communications
Porč, Jan ; Láčík, Jaroslav (referee) ; Pokorný, Michal (advisor)
This thesis deals with design of flush–mounted planar disc antenna suitable for use in vehicles. For each of the bands GSM900 and GSM1800, which are used in Czech republic, an independent antenna has been created. As a simulator of the electromagnetic field the program IE3D has been used. For the improvement of theoretical results an optimisation in the program MATLAB has been developed. As the optimisation method the genetic algorithms have been selected.
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Planar Antennas on Electromagnetic Bandgap Substrates
Horák, Jiří ; Dědková, Jarmila (referee) ; Škvor,, Zbyněk (referee) ; Raida, Zbyněk (advisor)
Planar antennas are used in several technical applications. The family of planar antennas contains microstrip antennas, which are very popular due to the low weight, low profile, simple manufacturing and easy mass production. Lower gain and excitation of surface waves are disadvantages of microstrip antennas. The propagation of surface waves can be efficiently suppressed if the conventional substrate is replaced by an electromagnetic bandgap (EBG) substrate. Microstrip antennas on EBG substrates have been presented in an open literature for several years. Nevertheless, no published work is devoted to the design of EBG substrates, which can suppress surface waves at several frequencies those cannot be covered by a single bandgap. In order to reach optimum parameters of designed antennas, selected global optimization methods are applied (genetic algorithms, particle swarm optimization, ant colony optimization).
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Modeling of antennas for communication near human body
Hodulák, Lukáš ; Hebelka,, Vladimír (referee) ; Vašina, Petr (advisor)
The bachelor thesis deals with problems of body-centric communications. The thesis also deals with the design of Yagi-Uda antenna with power supply substrate integrated waveguide structure (SIW) with the operating frequency of 60 GHz. The thesis is divided into a description of antennas and body-centric communications, description of Yagi-Uda antenna, types of Yagi-Uda antennas, the substrate integrated waveguide and SIW power divider. Then the thesis deals with selected Yagi-Uda antenna, transition between SIW and rectangular waveguide WR-15, antenna array and simulations in CST Microwave Studio. The last part of the thesis is a proposal itself, measurement and comparison of results measured with simulated ones.
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Patch antenna with switchable polarization
Havelka, Michal ; Pokorný, Michal (referee) ; Raida, Zbyněk (advisor)
The bachelor’s thesis deals with the analysis of basic planar antennas, the design methods, optimization and simulation in ANSOFT Designer. Attention is turned to the design of aperture coupled microstrip antennas. First, the antenna with a simple slot is designed. Second, the design of the ring slot coupled microstrip antenna is described. Both the antennas are designed for the operation frequency 2,45 GHz. The second part is devoted to the antenna with switchable polarization. Using three PIN diodes powered by lithium battery of 3-V, the linear polarization (both the horizontal one and the vertical one) and the circular polarization (both the right-hand one and the left-hand one) can be switched. The results were verified by experimental verification.
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