|
|
Subharmonic Mixers for Microwave Bands
Kintr, Jindřich ; Frydrych, Jiří (referee) ; Urbanec, Tomáš (advisor)
The task of this master’s thesis is design and implementation subharmonic mixer for the microwave band. Subharmonic mixer is based on the principle of antiparallel diode. In the first two parts are theoretically described mixers (subharmonic mixer) and topology suitable for implementation. Another work describes the design subharmonic mixer. The proposal is implemented in the program Ansoft designer. DPS is created in Eagle or in Ansoft Designer. The mixers are designed and implemented first on the lower frequency and consequently at higher frequencies (24,048 GHz and 47,088 GHz). Work also includes the measurement results of the mixers.
|
|
|
S Band Antennas for Cubesat Satellites
Bekeč, Alexander ; Cupal, Miroslav (referee) ; Urbanec, Tomáš (advisor)
This bachelor’s thesis is dedicated to antennas designed for use onboard miniaturized satellites CubeSat. The main goal of the thesis was to examine suitable antennas working in the S-band for use onboard this type of satellites, create their models and simulate them in the software ANSYS HFSS together with the CubeSat frame to find out its impact on the characteristics of antennas. One of these antennas was constructed together with CubeSat frame and measured in the RF anechoic chamber. Besides these, different types of satellite attitude stabilisation were examined, along with their influence on communication with ground station. Minimal half power beamwidths of antennas were analysed for both studied types of single axis stabilisation with consideration of communication with ground station located in the city of Brno.
|
|
|
Sun Sensor for I2C bus
Hodáňová, Adéla ; Povalač, Aleš (referee) ; Urbanec, Tomáš (advisor)
This thesis contains design of sun sensor. At first, it deals with different types of sensors, after which it focuses on selection of mode for connecting the sensor. After measuring all parameters, this thesis focus is determining of diode configuration in space. Next part of the thesis is choice of suitable microprocessor and its support circuits. Thesis ends with construction of the sun sensor and testing of sensor’s parameters.
|
|
|
LC Oscillators - Laboratory Exercise for BVMT Course
Červinka, Pavel ; Dřínovský, Jiří (referee) ; Urbanec, Tomáš (advisor)
This bachelor thesis speaks about LC oscillators. It describes basic principle and operation of oscillators. It introduces us with individual points of these oscillators, their charts and princip. This work deals two-points, three-points and feedback oscillators and oscillators with negative differential resistance. Then it was choosen, designed, further dismantled the Colpittts and one of the crystal oscillator. There are their wiring diagrams, printed circuit boards designed. Then these oscillators were made and are given their measured parameters.
|
|
|
Satellite Receiver with Integrated Antenna Tuner
Matoušek, Martin ; Pítra, Kamil (referee) ; Urbanec, Tomáš (advisor)
This work is focused on proposal of receiver with Integrated Antenna Tuner operating at 28 MHz. The design was primarily focused on simplicity and low power consumption. The receiver is adapted for SSB modulation. This work was realized for the transmission of audio signals. SSB modulation is far more efficient in terms of the radio spectrum used. First part of this thesis describes about the Antenna Tuner and block diagram of a receiver. Next parts are focused on proposal of individual blocks of the receiver, especially its most important parts. Finally, the overall evaluations of the design characteristics of SSB receivers with Integrated Antenna Tuner are discussed.
|
|
| |
|
|
Permittivity measurement of materials in microwave band – lab task
Fojtík, Jakub ; Urbanec, Tomáš (referee) ; Láčík, Jaroslav (advisor)
This work is concentrated on the development of laboratory task with a focus on measuring permittivity of materials in microwave band. For the measurement, two waveguide methods are used. The first method is used for determining of the permittivity of lossless materials by a method „shortening wavelength in the material“. The second method is used for determining of the permittivity of loss materials by a method „short – open“. Both methods are briefly described and used for determining permittivity of materials obtained from the data modeling in CST Microwave Studio. Then measuring workplace for both methods is realized and used for measurement of the permittivity of selected materials. Finally, the instruction for lab task with and measurement report is created.
|
|
|
Network for temperature measurement and data processing
Gociek, Krzysztof ; Urbanec, Tomáš (referee) ; Frýza, Tomáš (advisor)
Object of this work is creat universal wireless network for temperature measurement. Network consists from measuring modules which can measure outside temperature and inside temperature also. Modules send data to central modul by radio. In cetral module data are temporarily saveing and sanding to PC by USB cable. On PC we can generate temperature graphs. All network is easy and lowcost.
|
|
|
Wideband Amplifier Final Stage 5kHz - 1,5 GHz
Galajda, Jan ; Šebesta, Jiří (referee) ; Urbanec, Tomáš (advisor)
This work is focused on the problem of design of the wideband amplifier final stage, which is designed as a replacement for the old insufficient amplifier, which works in the frequency band from 5 KHz to 1.5 GHz. First part of the work is dedicated to theoretical introduction of the problem. Second part of the work describes the created matlab scripts for automatic measurement of the amplifiers parameters via SCPI commands. The third part describes choice of the new active element based on the measured parameters of the original amplifier.
|
|
|
RF Generator up to 4.4 GHz with ADF4350
Frydrych, Jiří ; Šádek, Václav (referee) ; Urbanec, Tomáš (advisor)
The aim of this work is design, realization, and measurement of wideband microwave generator, which is based on the ADF4350 frequency synthesizers. The generator uses the principle of mixing, for frequencies up to 2.2GHz. Higher frequencies are obtained through direct channels. The first part describes the theory of phase locked loop . The following section describes the parameters of the ADF4350 and their management. A PCB was also designed to control the generator with Atmel s AVR AT-mega32. The Generator software is written in AVR Studio in C programming language. The realized generator is housed in a stainless steel box and can be controlled using the keyboard and PC.
|
guest ::
