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Antenna system for car radar
Zechmeister, Jaroslav ; Hazdra, Pavel (referee) ; Láčík, Jaroslav (advisor)
This thesis deals with the design of lens antennas for automotive radar in 77 GHz bandwidth. The work explains methods of designing waveguides as well as horn antennas and dielectric lens. A simulation of three designed horn antennas is performed in CST Microwave Studio. Antennas with spherical and hyperbolical lens are simulated as well and subsequently optimized for maximal gain. The thesis also investigates effects of the lens permittivity on its properties. Furthermore, the work deals with a design of an antenna system with minimalized antenna coupling. Nylon, ABS and photopolymer lens are designed and compared afterwards. ABS and photopolymer lens were produced by 3D print
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Horn antenna with suppressed side-lobe radiation
Kaděra, Petr ; Puskely, Jan (referee) ; Mikulášek, Tomáš (advisor)
This master´s thesis is focused on the ways of possible realisation of the directive horn antenna with suppressed side lobes in the frequency bands 71-76 GHz and 81-86 GHz. In this thesis a detailed research of the feasible options including parameters comparison and assessment of pros and cons of the particular solutions has been performed. Among the specified technical requirements, the emphasis has been placed on the manufacturing options and low cost availability of the materials applicable for the given antenna. The main part of the thesis deals with the conical horn antenna loaded with a hyperbolic dielectric lens, further the antenna with flat dielectric lens based on a transmitarray and also the integrated elliptical lens antenna. The following part of the thesis deals with the possibilities of characterizing the properties of the dielectric material of the lens.
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Half-mode substrate integrated waveguide horn antenna
Černý, Matěj ; Mikulášek, Tomáš (referee) ; Láčík, Jaroslav (advisor)
This thesis is about technology of half-mode substrate integrated waveguide (HMSIW) and options proposal of horn antenna fouden on this technology. Based on gained findings HMSIW horn antenna was modeled in program CST Microwave Studio. Main attention is focused on impact geometrical parameters of antenna on it´s emitting and on reflecting ratio at the entrance of antenna. Achieved gain of main lobe was 6 dBi, which is misalignmented to required direction of angle 30°. Antenna has a working frequency 10 GHz.
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Antennas for energy transmission along the car roof
Škoda, Adam ; Hebelka, Vladimír (referee) ; Vélim, Jan (advisor)
The presented master’s thesis deals with antennas transmitting energy along conductive materials. Surface waves are used for energy transmission. According to its properties, the horn antenna was chosen for the problem solution. This thesis includes the theoretical analysis of surface waves, waveguides and horn antennas. The concept of antennas includes the comparison of two different materials and two different frequencies. From the set of 8GHz antennas, the structure of two antennas where one wearing the other was chosen as the most suitable. The FoamClad material was also selected due to achievement of better parameters and properties then material CuClad. This structure was designed by two identical horn antennas where the energy between them is transmitted via slot. The suitable feeding and parallel plates were designed, and further the current structure was modified to SIW structure. The designed antenna was manufactured and its properties were measured for further comparison with simulation results. Furthermore, achieved differences between simulated and real antenna are discussed.
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Planar parabolic reflector antenna
Procházka, Petr ; Pítra, Kamil (referee) ; Mikulášek, Tomáš (advisor)
This master's thesis deals with a design of a planar parabolic reflector antenna. The thesis is divided into several parts. The first section is dedicated to the theory of the parabolic antenna design and a basic introduction of the SIW technology which is used for the realization of an antenna prototype. The second chapter deals with the design of individual parts of the antenna (i. e. a primary and secondary reflector and an antenna feeder excited by a waveguide) for particular assignment. The third part is focused on modeling the designed antenna using ANSYS HFSS. Other parts of the thesis include a conversion of the proposed antenna to the SIW technology and a design of a transition between the antenna and a feeding waveguide WR15. The last part of the thesis deals with measuring of the reflection coefficient and the radiation pattern of the fabricated antenna prototype.
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In-car wireless power transfer
Cupal, Miroslav ; Polívka, Milan (referee) ; Raida, Zbyněk (advisor)
The thesis is focused on the design of antennas for wireless power transfer inside a car near the frequency of 8 GHz. In the last century, a number of scientists dealt with wireless transmission of energy with high power and long distances. Currently, attention is given to methods capable of transmitting energy with good effectively over a distance of meters for charging mobile devices, wireless sensors and other devices with low power consumption.
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Experimental wireless link in frequency band 60 GHz
Lambor, Jiří ; Polívka, Milan (referee) ; Raida, Zbyněk (advisor)
This thesis is focused on a wireless link operating in 60 GHz frequency band. In this band, the attenuation due to resonance of oxygen is high. Thanks to this property, we are able to ensure a proper insulation of communication links working in two close bands. The document compares commercially available modules of offered by different manufacturers for the operation in this band. The design, the simulation and the fabrication of a antenna and its feeder are described in the next part of the thesis. The system is fabricated using a SIW technology.
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Double ridge horn antenna for antenna measurement
Vašina, Petr ; Hertl, Ivo (referee) ; Láčík, Jaroslav (advisor)
The thesis deals with broadband antennas for measurement purposes. A ridged horn antenna has been selected for this concept, designed for the frequency range 0.9 GHz to 9 GHz. This work contains general theoretical description of antennas and further it focuses on a specific design of the ridged horn antenna, beginning with the calculation of its dimensions, modeling and optimization to obtain desired antenna properties. Finally, the antenna was constructed and measured. The reflection factor s11
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Free space method for measurement of complex permittivity
Nekovář, Jiří ; Hertl, Ivo (referee) ; Láčík, Jaroslav (advisor)
The aim of this thesis is the development of the workplace for the complex permittivity measurement by free space method. At the beginning of this thesis, the method is described. Further attention is focused on the discussions concerning electromagnetic properties of materials, comparison of the methods used for complex permittivity measurement, interactions of planar electromagnetic wave with planar infinite dielectric slab of general environment and description of radiation patterns of microwave antennas. In the rest of the thesis, the measuring workplace for the free space method is designed and fabricated. A pyramidal horn antenna is selected as a radiator. The antenna is designed with coax to waveguide transition in CST Microwave Studio, and than fabricated in two samples and measured. Finally, the fabricated measuring workplace is exploited for the complex permittivity measurement.
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