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Design of electronically reconfigurable filtering structures with modern active elements
Prát, Marek ; Kubánek, David (referee) ; Langhammer, Lukáš (advisor)
The aim of master's thesis was design of electronically reconfigurable filters. Adjustability of pole frequency or quality factor is possible. First part of thesis deals with theoretical analysis of filters, their operation modes, design of frequency filters using Signal-Flow graph method and parasitic analysis. The next part describes active elements used in thesis. In a third part, three reconfigurable filters are described and designed and their simulations and parasitic analysis are made. Last part deals with filter design in EAGLE and experimental measurement.
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Design of frequency filters with non-traditional transconductance elements
Gajdoš, Adam ; Vrba, Kamil (referee) ; Jeřábek, Jan (advisor)
The aim of Bachelor’s thesis was to study, design and practically realize controllable frequency filters, working in the current mode, using non-traditional active elements, containing a combination of transconductance amplifiers with current conveyors. Thesis deals in the theoretical part with the basic division of frequency filters, operating modes of circuits and design method of signal flow graphs, which are used for design of the circuits in the practical part. The next section describes all the active elements that are used for circuits realization. In the practical part five circuits are designed with the element VDCC and one circuit with CCTA. Simulation is performed on all circuits using a previously defined model of the real UCC. Last part of thesis describes the design of the PCB and the results of experimental measurements for chosen circuit.
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Laboratory device involving the high selectivity filters
Tuhý, Luboš ; Kovář, Jan (referee) ; Petržela, Jiří (advisor)
This project deals with the frequency filters of high selectivity. The area frequency filtering is fairly comprehensive and theoretically demanding discipline. The aim of this work isn’t to describe in detail and to include knowledge of the frequency filters, but only to clarify the aforementioned issues. In particular, we focus practically on filters working on other physical principles, especially on the crystal structure of partition filters and ceramic filters. The circuit simulation programs through classes Spice will be one of the parts of the theoretical analysis. There will be presented various options for implementing these filters, and the test products used in the design. The laboratory exercises dealing with frequency filtering and measuring engineered product will be made and based on the theoretical findings of this work. The laboratory exercises will include the developing of the model protocol.
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Electronically reconfigurable frequency filters
Gajdoš, Adam ; Langhammer, Lukáš (referee) ; Jeřábek, Jan (advisor)
The aim of the thesis was design of reconnection-less and electronically reconfigurable filters of SISO type with non-traditional active elements. Adjustability of bandwidth or quality factor is also required. First part of the thesis deals with theoretical analysis of filters, their operation modes and design of frequency filters using Signal-flow graph method aswell. Last but not least, electronical reconfiguration of transfer function and parasitic analysis was discussed. Another part describes active elements used in the practical part of thesis. Behaviors and design of active elements using existing circuits (e.g. UCC,EL2082) are described and their transformation into the Signal-flow graph form too. In the practical part five reconnection-less and reconfigurable filters of SISO type was designed using SNAP program. Simulations were done using Orcad program with ideal and real simulation models of active elements. Last part deals with filter design in EAGLE and experimental measurement.
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Frequency filters with difference current amplifier
Jirounek, Matěj ; Lattenberg, Ivo (referee) ; Vrba, Kamil (advisor)
This master´s thesis deals with the differential filters working in the current mode. It is dealt with the design methodologies of these filters and conversion circuits from voltage to current mode. Own work deals with 4 types of differential participation of structures. In this work there has been used programs SNAP and OrCAD. These programs were used for simulations of filters to proposed proper design. Results from this thesis is showed by graphs.
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Frequency Filters with Controllable Current Followers
Novotný, Matouš ; Herencsár, Norbert (referee) ; Koton, Jaroslav (advisor)
Submitted work engage in suggestion and realization of frequency-selection filters with usage one or more active devices CMI (Current Mirror and Inverter). The preamble of thesis is applied to theory of frequency-selection filters and possible usage of them. The projected circuit layouts are discussed next to would be possible change some of choice parameters of frequency-selection filter. The part of thesis is numerical suggestion of found solutions, their simulation in suitable program and realization.
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Design of adjustable fully-differential filters with current active elements
Polášek, Lubomír ; Koton, Jaroslav (referee) ; Jeřábek, Jan (advisor)
The master thesis deals with design of the fully differential frequency filters working in the current mode and is focused on possibilities of the natural frequency and the quality factor adjustment. At the beginning, there is a brief description of frequency filters and active elements (MO-CF, FD-CF and DACA), which are used in the thesis. Furthermore, simplified signal flow graphs design method and transformation of passive and active elements to the differential structures are described. The designs of four differential circuitries which provide possibility of tuning the natural frequency or quality factor by the gain of the DACA element are shown in the thesis. Simulation results made in OrCAD program with help of third-order models are included. The practical implementation of the differential frequency filter for tuning of the natural frequency by the DACA elements is shown in the last chapter.
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Voltage Conveyors in Linear Blocks
Dohnal, Pavel ; Jeřábek, Jan (referee) ; Koton, Jaroslav (advisor)
The main goal of this diploma thesis will be realization of tunable frequency filters using voltage conveyors, that are only little explored yet. At the beginnig of diploma thesis the frequency filters and their types will be defined. The theory of voltage conveyors based on principle of duality results from the character of current conveyors. Accordingly these active components will be closely presented. At first there will be defined individual types of voltage conveyors and their closer characteristics. Then design methods of frequency filters using unconventional active components will be described. There will be defined the method of the total admitance net, subsequently design using synthetic components and at the end there will be presented method using follow graphs that will be used to design concrete circuit solution. Using follow graphs method will be found circuit solutions of current structures with unconventional active components. During searching circuit solutions will be very important the posibility to operate the quality factor. That can be obtained by two ways. One way is the activ operation which is done by coeficients of the activ component. Other way is operating using the passiv component. There are found 26 circuits that realize condition of active operating using two active and four passive components. One of these circuits will be chosen and simulated in simulation program PSpice. To compare both methods of operation there will be compiled some circuit with passive operating with two active and five passive components and one of the passive components will be able to operate the quality factor. This circuit will be simulated in the simulation program PSpice again. The circuit will be real compiled and experimentaly measured in laboratory. Results of this measurement will be compared with calculated values and with values acquired from the simulations.
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FM Coincidence Detector - Laboratory Equipment
Mlčoch, Jiří ; Urbanec, Tomáš (referee) ; Baran, Ondřej (advisor)
This work is aimed at an analysis of frequency demodulation, design, simulation, and construction of a coincidence demodulator. Chapter 1 explains the basic characteristics of frequency modulated (FM) signals and provides an overview of the required signal bandwidth, the signal spectrum, and the signal-to-noise ratio after demodulation. Chapter 2 describes each type of FM demodulator separately, and it includes all significant types of demodulator for FM radio broadcast. The function of the coincidence demodulator and its characteristics are explained in detail. Chapter 3 contains a theoretical solution of the phase shift network. Calculated values of the circuit elements are verified by simulation with a view to the total harmonic distortion of the demodulator output signal. Chapter 4 describes the front-end circuit of the receiver. Here, the filter design and the mixer circuit description are provided. The final part of the thesis presents the applicable laboratory task.
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Laboratory device focused on the switched capacitor circuits
Urban, Lukáš ; Šotner, Roman (referee) ; Petržela, Jiří (advisor)
This Master`s thesis is focused on through acquaintance of principles of the function circuits with switched capaticors and posibility of their application mainly in frequency filters or signal generators. The origin of the switched capacitor circuits is mentioned at the beginning of the work. There are references to the first scientific work and scientists who have dealt with this issue. Maxwell`s idea: lossy element (resistor) replace with lossless element (switched capacitor) in electric circuit, is further described. In the next chapter of this work are listed types of switching capacitors and their use in simple RC filters and in structures of inverted or noninverted integrators and their application in more complex higher order filters. The advantages and disadvantages of SC circuits versus circuit composed of discrete components are shown. It is also listed a simple low-pass switched RC filter implemented with analogue multiplexer 4053. Using the LTC1043 integrated circuit, which structure and properties are described and analyzed in detail in the work, the 1st order aktive or pasive low and high pass filters were designed and subsequently simulated in the computer simulator OrCAD PSpice v.10. Another chapter deals with the integrated circuits higher order filters, structure and properties of the integrated filter LTC1060 are further analyzed here. Except this IC there are mentioned integrated filters commercially less available from the corporations Linear Technology and Maxim. The main objective of thesis was to propose and establish laboratory device and laboratory measurment focused on the switched capacitor circuits. The laboratory device has been designed with integrated circuits LTC1043 and LTC1060, which is demonstrated by using passive and active integrator, 2nd order band-pass and 4th order band-pass with Chebyshevovou approximation.
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