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La maîtrise de la communication et de l'information est un atout primordial dans les stratégies de pouvoir, qu'elles soient militaires, politiques ou commerciales. Celui qui est capable de transmettre l'information plus vite prend l'avantage sur les autres. Tel est le moteur de la croissance et du progrès dans le domaine des télécommunications. L'omniprésence grandissante des dispositifs communicants témoigne de l'expansion exponentielle qu'a connu ce domaine depuis les premières communications sans fil. À l'époque du all-in-one, la multiplication des applications au sein d'un même appareil nécessite l'utilisation de composants toujours plus performants et petits . Au cœur de ces systèmes, les filtres ont une importance grandissante. Dans un environnement spatial, les contraintes de fiabilité et d'encombrement sont particulièrement drastiques. Le choix des matériaux est par ailleurs limité, ce qui réduit les possibilités d'innovation. Cependant, l'amélioration de la précision et de la fiabilité dans les technologies de fabrication ouvre de nouvelles perspectives d'innovation et d'amélioration des composants. Ces travaux ont ainsi été motivés par ce souci d'apporter toujours plus de performance et de fiabilité, pour un encombrement moindre en tirant profit du potentiel offert par l'association du concept SIW et de la technologie LTCC. Les résultats mettent à jour de sérieuses dispersions technologiques. Cependant, le potentiel de l'association SIW/LTCC est démontré, et les difficultés rencontrées sont surmontables. Les filtres SIW en technologie LTCC présentent donc des atouts pour s'imposer comme une alternative sérieuse aux solutions existantes. / Control of communication and information is a key asset in the strategies of power, whether military, political or commercial. Whoever is able to transmit information faster takes advantage of others. This is the engine of growth and progress in the field of telecommunications. The growing ubiquity of communicating devices demonstrates the exponential growth experienced by this area since the first wireless communications. At the time of all-in-one, multiple applications within a single device requires the use of ever more powerful and small components. At the heart of these systems, filters are becoming increasingly important. In a space environment, reliability constraints and space are particularly dramatic. The choice of materials is also limited, which reduces the possibilities of innovation. However, the improvement of accuracy and reliability in manufacturing technologies opens new opportunities for innovation and improved components. This work has been motivated by the desire to bring more performances and reliability, a smaller footprint by taking advantage of the potential offered by combining the concept SIW and LTCC. The results update serious technological dispersions. However, the potential association SIW / LTCC is shown, and the difficulties are surmountable. SIW filters in LTCC therefore have advantages for itself as a serious alternative to existing solutions.

This paper introduces a high-gain, low-noise band-pass filter system for detection/amplification of small signals. In addition, related theory and methodology are described for a specific design implementation. Simulation and experimental results are presented and discussed. The purpose of the implemented design was to construct a band-pass filter system with 102 dB gain and with an output noise level of less than 0.8V. The design of the high-gain band-pass filter system was achieved mainly with the help of Filter Pro, LTSpice IV, and Multisim 12. The thesis provides important support for the project Marker Locator and constitutes a valuable reference for future active filter system design and small signal detection/amplification. / Marker Locator

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.

Submitted work engages in suggestion of frequency-selection filters with usage of more active elements of the MCMI (Multi-Output 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 with the active elements are discussed in terms of the impact of parasitic properties of the real models. The part of thesis is numerical suggestion of found solutions, their simulation in suitable program.

The main idea of this thesis is a propose by designing filters in Mathcad program. This paper deals with a basic principle in filters design and these principles are implemented into the Mathcad program. In the introductory part is described aproximation which was used in Mathcad script. In the other parts of this project is described program which was created on designed filters.

In this thesis is discussed a filter design of a band-pass substrate integrated waveguide filter on the frequency of 5 GHz. It also includes design theory, filter synthesis, filter analysis in the program CST Microwave Studio® and the results of measurement on a vector network analyzer. The analysis results are compared with the measured results. Good agreement between simulated and measured results is observed.

The theme of my diploma thesis is a realization of the high frequency amplifier with possibility to change its class between class A, B and C with output low pass and band pass filters. The output power is supposed to be at about 10 W in frequency range 3,5 MHz to 14 MHz. The thesis contains theory of amplifier respectively transceiver and filters. In next parts I will design, simulate, realize and measure created amplifier and filters.

My master’s thesis deals with methods of measuring the ultrasonic blood flow blood vessel with a detailed focus on Doppler ultrasound systems, which find application in the diagnosis of superficial vascular and obstetrics. The thesis is described a proposal indicating polydirectional Doppler system with a continuous carrier wave frequency of 4 MHz, the intensity of ultrasound 100 mW/cm2 and diameter D-shaped transducers 8 mm. As a result, the indicator will be able to measure blood flow velocity in the range of 5-40 cm/s, which appears to 3.5 digit display. After describing important theoretical assumptions, the work pays block diagram indicator. Furthermore, it examines the various functional blocks on the requirements imposed on them. It looks at the options of each functional block, and finally describes the implementation of the selected option and including peripheral solutions. Great attention is paid to the power of the indicator, where the power supply will be used 9 V battery. Create a symmetric voltage for operate amplifier and other auxiliary voltage will procure DC/DC converters. In conclusion, the work is located around the perimeter solutions indicator. The following draft for the production of double-sided PCB, its installation and a list of elements. The outcome of the thesis is complete documentation for the implementation of an indicator of blood flow, which allows us to obtain information on throughput vessels, especially the lower and upper limbs.