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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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Dualband Antenna for Global Navigation Satellite System
Mikulášek, Tomáš ; Lukeš, Zbyněk (referee) ; Láčík, Jaroslav (advisor)
This master’s thesis introduces to the reader with a modern antenna type the microstrip patch antennas. The most common types of microstrip antennas and their parameters and feeding methods are introduced in the theoretical section of this master’s thesis. This section deals with the circularly polarized microstrip antennas. Design of an active dual-band circularly polarized antenna for global navigation satellite application in the AWR Microwave Office is presented in the practical section. The proposed single-fed dual-band circularly polarized design is achieved using two stacked square microstrip patches. The antenna operates at the L1 + E1 and L5 + E5a frequency bands. Antenna preamplifier consists of a low-noise transistor and a dual-band band-pass filter. The thesis describes realization and measurement results of the dual-band antenna performance in the anechoic chamber. Measured results of the preamplifier performance are presented.
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Dual-Band Helix Antenna for WiFi band
Šrajbr, Michal ; Tkadlec, Roman (referee) ; Pítra, Kamil (advisor)
This master’s thesis is focused on the properties and types of helical antennas. The helical antenna work in the different modes. These modes are described in this thesis. There are also discussed possibility for design a dual-band helical antennas. The main aim of this work is the selection of a suitable solution and design a dual-band helical antenna for the WiFi band working at resonance frequencies of 2,4 GHz and 5 GHz. The simulation of this antenna was performed in the program CST Microwave studio.
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Dual-band antenna for in-car communication
Vörös, Ondrej ; Mikulášek, Tomáš (referee) ; Cupal, Miroslav (advisor)
This bachelor’s thesis deals with the design of dual-band planar antenna on a textile substrate. The proposed antenna is tuned to the ISM band 2,4 and 5,8 GHz for application in WLAN-in-car communication. The most common types of planar microstrip antennas, their parameters, feeding methods and methods of analysis are introduced in the first part of this work. In the practical section, the design of the dual-band antenna is presented with the use of the program CST Microwave Studio. The design of two concepts of dual- band antenna made on the FR4 substrate is transformed on the 3D textile and optimised to work at desired frequency bands. After then, the thesis describes fabrication and measurement of designed dual-band antennas in the anechoic chamber and in a car.
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Textile-Integrated Rf Energy Harvester
Kokolia, Martin
In the paper, we present a dual-band wearable rectenna operating in 900 MHz GSM band and 2.45 GHz ISM band. The rectenna was designed as a multilayer structure to reduce size while having a large enough aperture with a reasonable gain. The antenna was connected to the rectifier by a current probe via a textile substrate. The rectifier was conceived as a voltage doubler to maximize voltage on a load even with a very low received power. The manufactured antenna showed the gain 6.3 dBi at 900 MHz and 2.8 dBi at 2.45 GHz. The rectifier operated from -20 dBm and was measured up to -2 dBm with 19% efficiency for the GSM band and 17% efficiency for the ISM band.
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Dual-band antenna for in-car communication
Vörös, Ondrej ; Mikulášek, Tomáš (referee) ; Cupal, Miroslav (advisor)
This bachelor’s thesis deals with the design of dual-band planar antenna on a textile substrate. The proposed antenna is tuned to the ISM band 2,4 and 5,8 GHz for application in WLAN-in-car communication. The most common types of planar microstrip antennas, their parameters, feeding methods and methods of analysis are introduced in the first part of this work. In the practical section, the design of the dual-band antenna is presented with the use of the program CST Microwave Studio. The design of two concepts of dual- band antenna made on the FR4 substrate is transformed on the 3D textile and optimised to work at desired frequency bands. After then, the thesis describes fabrication and measurement of designed dual-band antennas in the anechoic chamber and in a car.
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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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Dual-Band Helix Antenna for WiFi band
Šrajbr, Michal ; Tkadlec, Roman (referee) ; Pítra, Kamil (advisor)
This master’s thesis is focused on the properties and types of helical antennas. The helical antenna work in the different modes. These modes are described in this thesis. There are also discussed possibility for design a dual-band helical antennas. The main aim of this work is the selection of a suitable solution and design a dual-band helical antenna for the WiFi band working at resonance frequencies of 2,4 GHz and 5 GHz. The simulation of this antenna was performed in the program CST Microwave studio.
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Dualband Antenna for Global Navigation Satellite System
Mikulášek, Tomáš ; Lukeš, Zbyněk (referee) ; Láčík, Jaroslav (advisor)
This master’s thesis introduces to the reader with a modern antenna type the microstrip patch antennas. The most common types of microstrip antennas and their parameters and feeding methods are introduced in the theoretical section of this master’s thesis. This section deals with the circularly polarized microstrip antennas. Design of an active dual-band circularly polarized antenna for global navigation satellite application in the AWR Microwave Office is presented in the practical section. The proposed single-fed dual-band circularly polarized design is achieved using two stacked square microstrip patches. The antenna operates at the L1 + E1 and L5 + E5a frequency bands. Antenna preamplifier consists of a low-noise transistor and a dual-band band-pass filter. The thesis describes realization and measurement results of the dual-band antenna performance in the anechoic chamber. Measured results of the preamplifier performance are presented.
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