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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.
1

Spektrální analyzátor N1996A-503 a nejistoty měření / Spectrum Analyser N1996A-503 and Measurement Uncertainty

Trojan, Martin January 2011 (has links)
The main target of this master’s thesis is to introduce the reader with the spectrum analyzer, Agilent N1996A CSA. This work explains all the functions of this measuring instrument, control elements and presents some technical parameters. The next part of this thesis deals with the measurement of coaxial cables, so that is why a whole chapter is devoted to coaxial cables and conductors in general. The rest of this thesis deals with issues of measurement uncertainties. This part contains the general procedure for the evaluation of uncertainty, followed by a practical part. The practical part contains measurement of distance to fault and return loss. Measurements were made on 4 samples of coaxial cable. At the end of the practical parts the measured values including the uncertainties and results are summarized in the final paragraph.
2

Duplexer pro pásmo 5,6 GHz / Duplexer for the frequency band 5.6 GHz

Opletal, Prokop January 2011 (has links)
The aim of this master’s theses was a designing of duplexer working in non license frequency band 5.6GHz. The theses is concerning with selection of suitable concept for a given duplexer, with creating a model in software for simulation of distribution of electromagnetic field and with subsequent implementation of duplexer and verifying its parameters.
3

Návrh diplexeru na bázi koaxiálních rezonátorů / Design of diplexer based on coaxial resonators

Štěpánek, Michal January 2013 (has links)
This thesis deals with the analysis of coaxial cavity filters and synthesis of generic topology of these filters. Transfer function comes out the synthesis, which is based on low-pass prototype and similarity with real structure. The next aim of this thesis is to build the basic software for coaxial cavity filters synthesis from engaged characteristic parameters of the filter. This work also includes the analysis of coupling matrix synthesis based on transfer function, where we can use direct coupling or cross-coupling between resonators. The last point is focused on the diplexer filter based on specified parameters and obtained coupling matrix. Entire diplexer model is optimized using Tuning-Space Mapping method.
4

Měření permitivity materiálů koaxiální sondou / Permittivity measurement of materials by coax probe

Ryba, Ivan January 2015 (has links)
This thesis describes possibilities of measuring permittivity of various materials, especially with coaxial probe method. It describes character of measuring method, hardware requirements and how to calculate values from the measured. Objective of this thesis is to design measuring station for measuring permittivity of materials with coaxial probe including calibration set. Code in Matlab is also programmed and whole station is tested with known samples to discuss measurement accuracy.
5

Metody přesného měření nízkých impedancí / Methods of Accurate Measurement of Low Impedances

Mašláň, Stanislav January 2021 (has links)
Overall topic of presented thesis is development of methods of measurement of low impedances below 10 Ohm in a frequency range up to 1 MHz. The thesis comprises of three main parts. First part of thesis describes design of unique and simple calculable standards of resistance that are used for calibration of the bridge and as the reference standards for the calibrations. Next part of theses is focused on design of digital sampling bridge in various topologies suitable for measurement of various types of impedance standards up to frequency of 1 MHz. The thesis describes the HW components, data processing and corrections scheme allowing the designed bridge to reach expanded uncertainties (k=2) below 0.005% and 250 µrad at 1 MHz. One of the key points of the proposed corrections scheme is unique automatic linearity calibration method requiring minimal operator's effort. The theses also describes integration of Spice model of the bridge the bridge SW that allowed validation of functionality of the bridge and also analysis of uncertainty contributions related to interferences between the bridge components. The last part of the thesis shows selection of measurements of known impedances and international comparisons that proofs performance of the bridge.
6

Optimalizace koaxiálních filtrů metodou Tuning-Space Mapping v CST / Optimizing coaxial filters by Tuning-Space Mapping in CST

Wolanský, David January 2010 (has links)
This thesis deals with optimization of coaxial cavity filters. It thoroughly describes optimization method Tuning – Space Mapping (TSM) in CST Studio. It focuses on the explanation of the fine and the coarse model and their mutual link. The whole algorithm is illustrated and tested on the third-order coaxial cavity filter working in the band of 880 – 960MHz. In order to check the function of TSM, the algorithm is applied on fourth-order filter, triplet filter and quadruplet filter. Another part of the thesis focuses on the automatization of the whole optimization procedure. Macros for automatic determination of calibration constants and automatic calibration process between the coarse and the fine model are proposed and programmed in CST. The complete optimization procedure is applied on optimization of seventh-order filter with two cross couplings.
7

Analýza mikropáskových antén / Analysis of microstrip antennas

Kozák, Filip January 2010 (has links)
This work deals with the method for analysis of one-port microstrip circuits which is called as contour-integral method. The general procedure for evaluating of important parameters concerning the analysis of microstrip antennas is given. Next, the geometrical parameters necessary for the calculation of elements in U and H matrices are numerically solved. With the help of these matrices, the input impedance or the reflection coefficient can be easily found.
8

Systém pro přesné měření elektrické délky koaxiálních kabelů / System for Precise Measurement of Electrical Length of Coaxial Cables

Podr, Michal January 2015 (has links)
This thesis describes a study of the measuring methods determining the electrical length of coaxial cable without using a vector network analyzer. First, a general theory of management and its various parameters is briefly discussed. This section is focused more specifically on the coaxial cable and its parameters. The next part is graphically analyzed process considerations in the design of measurement methods and outlined the block structure of the system. The third section describes the working process, prototype testing of the bridge, its measurement and design of the measuring system. In the fourth part the software is described. In conclusion, the results of the work are discussed, accuracy of the measurement system, the obtained parameters chosen with regard to the principle of the measurement system and the overall evaluation of the applicability in practice.
9

Program pro návrh společných TV kabelových rozvodů / Program for design of CATV

Sedláček, Jan January 2010 (has links)
The main task of this master’s thesis is to create an interactive computer programme for the design of small and medium television cable circuits. The first part of this document describes main conceptions of a modification and a distribution of television signals. There are also introduced basic topologies of small and medium sized distribution networks, some passive and active elements in the circuit including their usage. There is also described an algorithm for calculation of circuit’s values. The second part contains a detailed description of created programme with all of its functions. A part of this document is made by a sample calculation of the four variants of circuit and its comparison with computer calculation. In suplement are included selected parts of source code.
10

Knihovna stavebních prvků koaxiálního filtru pro CST Microwave Studio / Library of building elements of coaxial filters for CST Microwave Studio

Vorek, Jiří January 2010 (has links)
This thesis deals with development of tool – macros which help to create coaxial cavity filters. It describes problematic design of complex structures at CST Studio Suite 2009. For this purpose macros supporting coarse and fine model to method Tuning – Space Mapping (TSM) was made. This means creating fine model at CST MWS and coarse model at CST DS.

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