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Network with capacitor microphone using FM modulation
Lapáček, Petr ; Říha, Kamil (referee) ; Káňa, Ladislav (advisor)
In bachelor's thesis I was interested in quality of the electrostatic transducer. I have described a theoretic pieces of knowledges in parts of FM modulations and the variables crystals oscillators. I have tried to propose a conception of the condenser mikrophone in the high-frequency circuit where one of the main part was the crystal oscillator, which part was the capacitor transducer, in capacity element representative uncertain capacities. By this way I have tried to create the modulator, whose modulation depend on the actual changes of capacities in the electrostatic changers. Finally I have interested in the demodulation in this way of creating the HF signal by the help of detection unit TDA7000 and likewise setup of integrated circuit.
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Evaluation of Traffic Noise
Mejzlík, Martin ; Spies, Karel (referee) ; Kudrna, Jan (advisor)
This thesis deals with issue of traffic noise, its measurement and data evaluation. Theoretic part of my work concretes basic information about acoustics and also describes and analyzes traffic noise sources of tire/pavement. Next part deals with quite pavement and with measurement methods of traffic noise. Practical part of my thesis contains description, results and evaluation of realized measurement with methods CPX and SPB.
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Acoustic sensor with ICP power and electronic datasheet
Dvorský, Pavel ; Klusáček, Stanislav (referee) ; Havránek, Zdeněk (advisor)
The task of this Bachelor’s thesis is to introduce IEEE 1451.4 standard and connection of sensors with ICP supply to data acquisition systems. It deals with realization of acoustic pressure sensor (microphone) with ICP (CCLD) supply and possibility of saving real parameters of this sensor into transducer electronic datasheet (TEDS). Finally there is shortly described work with TEDS in LabVIEW programming environment.
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Tube microphone preamplifier
Čacký, Adam ; Hruboš, Zdeněk (referee) ; Brančík, Lubomír (advisor)
The theme of the master´s thesis is design a microphone preamplifier which uses vacuum tube as a main amplifying element. Part of the work is theoretical assumptions for the optimal design and implementation of peripheral involvement, comparing the properties of components used and the resulting parameters of modeled device. The thesis also includes a proposal of the source unit for supplying all parts of the preamplifier. The results are accompanied by circuit simulations and laboratory measurements of the main parameters of the designed device.
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Digital microphone signal processing
Vykydal, Martin ; Macho, Tomáš (referee) ; Havránek, Zdeněk (advisor)
The aim of this work is to implement digital filters into programmable gate array. The work also includes a description of the MEMS technology, including comparisons with the technology of MEMS microphones from various manufacturers. Another part is devoted to the Sigma-delta modulation. The main section is the design and implementation of digital CIC and FIR filters for signal processing of digital microphone, including simulation and verification of properties of the proposed filter in Matlab.
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Noise Source Identification Using Beamforming
Kurc, David ; Míča, Ivan (referee) ; Schimmel, Jiří (advisor)
This master's thesis is focused on the noise source identification using microphone arrays and beamforming as the signal processing method. It describes parts of such a system and provides a comparison with other systems that serve a similar purpose (eg. NAH). Various types of microphone arrays are mentioned with their influence on the resulting ability to identify the noise source. We are further focusing on Delay-And-Sum technology, on which we are explaining the basic principles and constraints of beamforming. The practical part describes the implementation of the DAS method in MATLAB and C language, the specific structures of built microphone arrays and assembly of complete systems capable of identifying sources of noise. These systems were tested by performing a practical experiment. Achievements in the form of distribution maps of acoustic energy in the focused space are interpreted in the last chapter.
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Measurement and analysis of phonocardiographic signal
Všetula, Petr ; Kolářová, Jana (referee) ; Kolář, Radim (advisor)
This work is engaged in measurning and analysis of phonocardiographic signal. Effect of characteristics and parameters of used parts is examined due to quality of measurement of these signals. The emphasis is put especially on the amplifiers and microphones. The measurment is done by measure card PCI6221E. Data processing and analysis is proceeding by the help programmes, which are created in programmatic environmen LabView.
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