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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Vícevrstvá Yagiho anténa pro pásmo 60 GHz / Stacked Yagi antenna for 60 GHz frequency band

Janečka, Martin January 2013 (has links)
This diploma thesis deals with the design and simulation of multi-layer stacked Yagi antenna at the frequency of 60 GHz. At work are proposed and compared two ways of antenna feeding methods. Based on the results obtained, antenna is fed by substrate integrated waveguide. The proposed antenna has been optimized in terms of gain and impedance matching at the specified frequency. The correct functionality of the antenna was verified by simulation program CST MWS 2011. Simulation results were verified experimentally.
12

Efficient radio frequency power amplifiers for wireless communications

Cui, Xian 10 December 2007 (has links)
No description available.
13

Návrh logaritmicko-periodické antény / Design of log-periodic antenna

Kliha, Marek January 2008 (has links)
This diploma thesis deal with the design of log-periodic antenna. The log-periodic antenna is self-complementary and broadband antenna. Antenna self-complementary structures are described only by angles. Input impedance of log-periodic antenna is equal to theoretical impedance ohms. The input impedance and radiation patterns of broadband antenna structures are independent of frequency over theoretically unlimited bandwidths. The log-periodic antennas provide linearly polarized radiation pattern. In this thesis is designed antenna for bandwidths 1 to 5GHz. In this diploma thesis is introduced design balanced unit, this is compound broadband balun and broadband impedance transformer. The broadband balun is based on conversion of microstrip line to balanced stripline. The Klopfenstein impedance taper is used for design. For simulation was used software from firma Zeland software IE3D.
14

Miniaturní anténa pro mobilní aplikace / Miniature antenna for mobile applications

Šmarda, Marek January 2013 (has links)
This work deals with the most famous constructions of planar antennas. The work analyses selected methods of connecting planar antennas' charging with the possibility of impedance adaptation. An important part of the work consists of description of techniques for increasing bandwidth and conversely techniques for reducing the dimensions which are important for the design of planar antennas for mobile devices. The antennas were designed by means of theoretical basis and their properties were examined in the electromagnetic field simulator. The selected antenna model was constructed and its parameters were measured experimentally. The matching circuit for the antenna to tune it to different resonant frequencies was designed and constructed.
15

Vysokofrekvenční měřič výkonu / RF power meter

Hlaváč, Štěpán January 2013 (has links)
This master’s thesis describes various principles of measurement of electromagnetic waves in a free space and on a line. Used sensors and their real parameters are given for every method. The analysis of protections of high-frequency inputs of measuring instruments is done here and the most suitable method and protections of input for realization are chosen. The analysis of design of secondary protection of high-frequency input is done in this project. The protection of input is realized and measured. The suitable method of measurement is chosen as well as the sensor for measurement of power. The block diagram and circuit diagram of the meter of power are designed. According to designed conception the measuring instrument for measurement of power is realized and its single qualities are measured during the realization. In the final part its precision is measured and the evaluation of results is done.

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