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prof. Ing. Miloš Mazánek, CSc.

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Reconfigurable Antenna Array Testbed for Quantized Controlling

  • DOI: 10.1109/ACCESS.2024.3356358
  • Odkaz: https://doi.org/10.1109/ACCESS.2024.3356358
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Contemporary beam-forming antenna arrays often use a large number of individual elements, sometimes hundreds or more, to achieve high gain for advanced applications like radar, space communication, and next-gen cellular networks. These arrays are complex and costly due to the need for precise amplitude and phase adjustments across the elements. The feeding network complexity leads to signal losses, reduced efficiency, and higher noise. Current research aims to simplify arrays, reduce active elements needing frontends, and streamline the feeding network, considering non-uniform, sparse, parasitic, or reflective arrays. Challenges arise from element coupling and imperfect models of high-frequency materials and electronic components. Therefore, in addition to simulations, practical experimentation remains vital. This paper focuses on designing a novel 3 × 3 element antenna array with digital quantized control. We explore the impact of quantized control on beamforming and plan to validate simplified orthogonal optimization methods with limited quantization depth. The proposed antenna array is applicable to 2400 GHz band research, including arrays with parasitic elements and switchable polarization for individual elements.

Effect of erbium-doped fiber amplifier loss compensation on 5G new radio millimeter-wave seamless transmission over analog fiber and free space optical fronthaul at 60 GHz

  • DOI: 10.1117/1.OE.61.6.066104
  • Odkaz: https://doi.org/10.1117/1.OE.61.6.066104
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    We demonstrate a fifth generation (5G) new radio (NR) signal transmitted by an analog optical and seamless antenna wireless connection at the frequency band of 60 GHz to exploit a high-frequency unlicensed frequency range. An optical frequency doubling technique, using two Mach–Zehnder modulators operating in a carrier suppressed and linear regime, respectively, was adopted to obtain the desired millimeter wave frequency at the photodetector’s output. The proposed system was tested with the 5G NR signals with a maximum bandwidth of 200 MHz and 64 quadrature amplitude modulation format. It was shown that the signal transmitted through the optical fiber and free space optical link with 1 m long seamless antenna transmission at 62 GHz was capable of meeting the signal quality requirements in terms of error vector magnitude. Moreover, the system phase noise performance showed an almost negligible difference between the various system configurations.

Deep reflector prime focus feed for space communication

  • DOI: 10.1049/tje2.12055
  • Odkaz: https://doi.org/10.1049/tje2.12055
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    In this paper, design of a prime-focus feed for a deep reflector, Earth–Moon–Earth space communication system is described. The feed is based on a circular waveguide equipped with two chokes in order to minimise sidelobes and illuminate the deep dish with a high aperture efficiency of 70% . Based on sun noise measurements, it is estimated that the antenna system presents very low noise temperature values, below 30 K, making this feed favourable for space communication.

Měření EMC v měřicích komorách

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: XXIX. konference Radiokomunikace 2019 - Sborník přednášek. Pardubice: Unit s.r.o., 2019. p. 275-288. ISBN 978-80-87942-57-4.
  • Rok: 2019
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Different arrangement of measurement chambers for testing of electromagnetic systems were introduced. Measurement of EMC (radiation as well as susceptibility) Anechoic, semianechoic, reverberarion chambers, as well as TEM a GTEM arrangement were described.

A Dual-Band Reflector Feed in Coaxial Configuration for Satellite Communication

  • DOI: 10.1109/MAP.2018.2859168
  • Odkaz: https://doi.org/10.1109/MAP.2018.2859168
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This article presents the design, simulations and measured results of a dual-band coaxial feed for satellite communication in the 2.4 and 10.45 GHz bands. The feed is designed for communication with the geostationary satellite. Es´hail 2 (scheduled to be lanched in late 2018), which will be equipped with a public amateur radio transponder covering nearly one-third of the Earth´s surface. A communication link can be established using a relatively low-power transmiller (Tx) employing conventional microwave technology. The proposed feed operates with linear polarization at the X-band and circular polarization at the S-band and has similar radiation patterns in both bands, providing high aperture efficiency for a broad range of reflector focal-to-diameter (f/D) ratios.

AToM: A Versatile MATLAB Tool for Antenna Synthesis

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The Antenna Toolbox For MATLAB (AToM), originally an in-house academic tool, has been transformed into a complete MATLAB toolbox, capable of modeling, discretizing and calculating arbitrarily shaped planar radiators while analysing the results. All tasks can be performed directly in MATLAB. The majority of the code allows its direct modification. AToM supports the latest features, used predominantly in the realm of electrically small antennas, namely modal decompositions, evaluation of fundamental bounds, and other techniques based on the source concept.

Historie, současnost a budoucnost anténní techniky

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: XXVIII. konference Radiokomunikace - Sborník přednášek. Pardubice: Unit s.r.o., 2018. p. 131-140. ISBN 978-80-87942-45-1.
  • Rok: 2018
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Antény jsou prvky radiokomunikačních soustav, které patrně jako jediné budou přežívat v analogové formě. Vše ostatní přejde z hlediska rychlosti a kvality přenosu na digitální formy. Ve spojení s optimalizačními procesy to umožní měnit směrovou charakteristiku i frekvenční pásmo. Antény budou stále více integrovanými prvky vstupních obvodů.

Pre-Assessment of Radiated Fields from Small Electronic Submodules

  • DOI: 10.13164/re.2018.0640
  • Odkaz: https://doi.org/10.13164/re.2018.0640
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    A novel approach to the evaluation of electromagnetic field radiated from devices by using a small shielded enclosure in presented. Several EMC problems can be identified by employing the computations of a Radiated Model device, such as the model the Submodule-on-Motherboard structure described here. The combination of a numerical approach, through a validation model and measurements, must be done during the design phase in multiple iterative loops to minimize the risk of non-compliance of the final qualification proces. Ths novel combined approach requires little investment and is highly efficient for industrial applications.

Europe and the Future for WPT COST Action IC1301 Team

  • DOI: 10.1109/MMM.2017.2680078
  • Odkaz: https://doi.org/10.1109/MMM.2017.2680078
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This article presents recent European-based contributions for wireless power transmission (WPT), related to applications ranging from future Internet of Things (IoT) and fifth-generation (5G) systems to highpower electric vehicle charging. The contributors are all members of a European consortium on WPT, COST Action IC1301 (Table 1). WPT is the driving technology that will enable the next stage in the current consumer electronics revolution, including batteryless sensors, passive RF identification (RFID), passive wireless sensors, the IoT, and machine-to-machine solutions.

A Simple S/X Dual-Band Coaxial Feed for Satellite Communication

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Design concept of coaxial waveguide feed is often used for multi band antenna feeds. Cofiguration described in a paper has advantages in common phase center in the same aperture plane (for two bands), very high port to port isolation and easy of assembly.

Analysis of Magnetic Field of Thin-Wall Air Induction Coil of Arbitrary Cross Section With the Help of Scalar Magnetic Potential

  • DOI: 10.1109/TMAG.2015.2472526
  • Odkaz: https://doi.org/10.1109/TMAG.2015.2472526
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The analysis of magnetic field of a thin-wall air induction coil with a shape of finite cylinder of arbitrary cross section is described. The result of the analysis is a method for finding the scalar magnetic potential of the coil with the help of mutual inductance of the coil and the elementary loop. The magnetic flux density of the coil is found as the gradient of the scalar magnetic potential. The proposed analysis is verified using two examples, which are thin-wall air coils with a shape of finite cylinder of circular and rectangular cross sections. The magnetic flux density calculated by the presented method is compared with other approaches for both examples with excellent agreement.

Anténa a co je víc

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Referáty přednesené na 44. semináři Pravidelné setkání zájemců o mikrovlnnou techniku. Praha: Česká elektrotechnická společnost, 2016. ISBN 978-80-02-02654-9.
  • Rok: 2016
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Článek popisuje vývoj v oblasti analýzy a návrhu antén. Jsou zmíněny nové trendy a velmi aktuální směry v oblasti struktur jako jsou metamateriály, frekvenčně selektivní povrchy chirální materiály atd. Jsou popsány metody charakteristickým módů a cesty vedoucí k syntéze antén. Zahrnuty jsou vědecké výsledky dosažené na katedře elektromagnetického pole ČVUT v Praze

Implantable Semi-Active UHF RFID Tag With Inductive Wireless Power Transfer

  • DOI: 10.1109/LAWP.2016.2520663
  • Odkaz: https://doi.org/10.1109/LAWP.2016.2520663
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The objective of this paper was to design a compact, battery-less system for an implantable semi-active UHF RFID tag with inductive wireless power transfer for the human body. An RFID chip of the tag, combining powering from a reader by communication and from another source through inductive wireless power transfer, was used. Tag sensitivity for communication was increased by about 21 dB with the help of wireless inductive powering when compared to tags which did not employ this system. Communication and powering circuits were integrated within compact structures on the sides of the reader and the tag. The structure for communication and powering on the side of the reader consists of a centre-excised Archimedes spiral antenna and a circular loop respectively. Similarly, the structure on the side of the tag consists of a folded dipole antenna for communication and a rectangular loop for powering.

Inductive Wireless Power Transfer for Human Body Implantable UHF RFID Tag

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This contribution deals with a design of a system with RFID communication and inductive wireless powering for a human body implantable tag. A chip of the tag employs powering from an RFID reader by communication and from another source with the help of inductive wireless power transfer. Circuits for communication and powering on the reader and tag sides were designed as compact planar structures. The reader side structure comprises a centre-excised Archimedes spiral antenna for communication and a circular loop for powering. The tag side structure integrates a folded dipole antenna for communication and a rectangular loop for powering. The communication sensitivity of the tag was increased by about 21 dB when the additional inductive wireless powering was used.

Semi-Active 866 MHz RFID Implantable Tag Fed by 6.78 MHz Inductive Wireless Power Transfer

  • DOI: 10.1109/EuMC.2016.7824419
  • Odkaz: https://doi.org/10.1109/EuMC.2016.7824419
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The paper presents a compact battery-less semi-active UHF RFID tag powered by an inductive wireless power transfer designed to be implanted into the human body. Communication runs at frequency of 866 MHz whereas powering is performed at frequency of 6.78 MHz to reduce losses. Tag sensitivity for communication was increased by about 21 dB with the help of inductive wireless powering when compared to a tag which did not employ this powering. Communication and powering circuits were integrated within compact structures on the sides of the reader and the tag. The reader side consists of a center-excised Archimedes spiral antenna for communication and a circular loop for powering. The tag side consists of a folded dipole antenna for communication and a rectangular loop for powering.

Systémy bezdrátového napájení

Fire Emissivity Detection by a Microwave Radiometer

  • DOI: 10.1109/LGRS.2015.2474121
  • Odkaz: https://doi.org/10.1109/LGRS.2015.2474121
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    In this letter detectability of a fire by a microwave radiometer is investigated. In order to understand the fire from radiometric point of view, parameters of the fire emissivity had to be determined. Therefore representative fire types were analyzed and fire spot emissivity values have been derived from measured data. Four typical burning fuels were tested – gasoline, wood, flood-trash and straw. Also parameters of a scenario in which the fire temperature was changed was set and analyzed in order to investigate detectable radiometric contrasts. As a result specific values of a fire spot emissivity are presented. Obtained results can provide indispensable inputs for designers of microwave fire detection instruments.

The Antenna Toolbox for Matlab (AToM)

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This contribution presents recent development of the Antenna Toolbox for Matlab (AToM). The toolbox utilize novel theoretical findings related to characteristic mode decomposition and the so-called source concept, by which all antenna characteristics are represented solely by means of currents.

Trendy v anténní technice

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: XXV. konference Radiokomunikace - Sborník přednášek. Pardubice: UNIT, 2015. pp. 237-246. ISBN 978-80-905345-6-8.
  • Rok: 2015
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Článek pojednává o posledních výsledcích v návrhu a vývoje antén. Jeden zmíněný směr souvisí s novými výpočetními možnostmi a numerickými metodami v problematice charakteristických módů, novými strukturami (metamateriály) a novými aplikacemi antén. Druhý směr se orientuje do nových struktur na bázi grafenů a dalších struktur, kde je třeba hledat nové přístupy k podstatě ve fyzice a chemii.

A Method for Evaluating Radiation Efficiency Based on a Modal Approach

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Radiation efficiency is an important parameter, especially for electrically small antennas. It can be computed directly from the method-of-moments impedance matrix, and also more generally by employing modal decomposition through characteristic modes. This advantageously enables us to study separately the effect of the radiating shape and the feeding. The proposed method does not require any modification of the Electric Field Integral Equation implementation. A perfectly conducting antenna is considered as the only input to the modal decomposition. The conductive losses are taken into account once the surface currents are calculated. Good agreement is observed for the proposed treatment of the skin effect. Verification of the method is numerically performed on an fractal antenna, a thinstrip Sierpinski curve of various iterations. A full-wave software FEKO with implemented IBC is used for comparison purposes.

Research on Compact Reflector Feeds for Space Applications

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This contribution describes our recent efforts in the research and design of special prime-focus feeds for reflector antennas intended for space communication using the Moon Bounce technique. Two contrasting structural designs are presented, illustrating the concept of multiband / multipolarization signal propagation. Besides space communication, these feeds may also be used in terrestrial radar and sensor systems.

The Radiation Q-Factor of a Horizontal lambda/2 Dipole Above Ground Plane

  • DOI: 10.1109/LAWP.2014.2329421
  • Odkaz: https://doi.org/10.1109/LAWP.2014.2329421
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Closed-form equations are given for radiation quality factor of a thin-wire =2 dipole above an infinite electric ground plane. Particular results of interest include a simple formula for a small separation between the dipole and the ground and for one dipole in free space.

Wireless Power Transmission: R&D Activities Within Europe

  • DOI: 10.1109/TMTT.2014.2303420
  • Odkaz: https://doi.org/10.1109/TMTT.2014.2303420
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Wireless power transmission (WPT) is an emerging technology that is gaining increased visibility in recent years. Efficient WPT circuits, systems and strategies can address a large group of applications spanning from batteryless systems, battery free sensors, passive RF identification, near-field communications, and many others. WPT is a fundamental enabling technology of the Internet of Things concept, as well as machine-to-machine communications, since it minimizes the use of batteries and eliminates wired power connections.WPT technology brings together RF and dc circuit and system designers with different backgrounds on circuit design, novel materials and applications, and regulatory issues, forming a cross disciplinary team in order to achieve an efficient transmission of power over the air interface. This paper aims to present WPT technology in an integrated way, addressing state-of-the-art and challenges, and to discuss future R&D perspectives summarizing recent activities in Europe.

Acceleration Techniques in Matlab for EM Community

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This paper describes some acceleration techniques in Matlab. Here, we strongly focus on acceleration of computational routines via High Performance Computing (HPC), which - in terms of Matlab software - includes parallel and distributive computing on CPU(s) and GPU computing. We also introduce an in-house antenna tool which is based on the Method of Moments and Theory of Characteristic Modes. Two numerically challenging examples are presented and then solved in Matlab

Clutter Reduction Based on Principal Component Analysis Technique for Hidden Objects Detection

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This paper brings a brief overview of the statistical method called Principal Component Analysis (PCA). It is used for clutter reduction in detection of hidden objects, targets hidden behind walls, buried landmines, etc. Since the measured data, imaged in time domain, suffer from the hyperbolic character of objects' reflections, the utilization of the Synthetic Aperture Radar (SAR) method is briefly described. Besides, the basics of PCA as well as its calculation from the Singular Value Decomposition are presented. The principles of ground and clutter subtraction from image are then demonstrated using training data set and SAR processed measured data.

Compact Circular/Linear Polarization Dual-band Prime-focus Feed for Space Communication

  • DOI: 10.1155/2012/860951
  • Odkaz: https://doi.org/10.1155/2012/860951
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    We propose a novel, compact, prime-focus antenna feed for space communication. The feed requires full-wave simulator optimization for a given parabolic reflector and is designed to operate simultaneously on two bands, offering LHC/RHC polarizations for the 13 cm band and V/H polarizations for the 70cm band. With performance results confirmed by measurement, it has been verified in practice that this compact feed is suitable for use in a low-noise Earth-Moon-Earth communication link.

Measurement of Magnetic Flux Density Vector

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This contribution presents a measurement of harmonically changing magnetic flux density in the free space. The components of magnetic flux density vector are measured separately as effective value in the time. The measuring probe and its calibration are described in detail.

Modal Resonant Frequencies and Radiation Quality Factors of Microstrip Antennas

  • DOI: 10.1155/IJAP
  • Odkaz: https://doi.org/10.1155/IJAP
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The chosen rectangular and fractal microstrip patch antennas above an infinite ground plane are analyzed by the Theory of characteristic modes. The resonant frequencies and radiation Q are evaluated. An novel method by G. Vandenbosch for rigorous evaluation of the radiation Q is employed for modal currents on a Rao-Wilton-Glisson (RWG) mesh. It is found that the resonant frequency of a rectangular patch antenna with a dominant mode presents quite complicated behaviour including having a minimum at a specific height. Similarly, as predicted from the simple wire model, the radiation Q exhibits a minimum too. It is observed that the presence of out-of-phase currents flowing along the patch antenna leads to a significant increase of the Q-factor.

On the Modal Resonant Properties of Microstrip Antennas

  • DOI: 10.1109/EuCAP.2012.6206511
  • Odkaz: https://doi.org/10.1109/EuCAP.2012.6206511
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The chosen rectangular and fractal microstrip patch antennas above an infinite ground plane are analyzed by the Theory of characteristic modes. The resonant frequencies and radiation Q are evaluated. An method by G. Vandenbosch for rigorous evaluation of the radiation Q is employed for modal currents on a Rao-Wilton-Glisson (RWG) mesh. It is found that the resonant frequency of a rectangular patch antenna with a dominant mode presents quite complicated behaviour including having a minimum at a specific height. Similarly, as predicted from the simple wire model, the radiation Q exhibits a minimum too. It is observed that the presence of out-of-phase currents flowing along the patch antenna leads to a significant increase of the Q-factor.

Short-term Prediction and Detection of Dynamic Atmospheric Phenomena by Microwave Radiometer

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Specific utilization of a microwave radiometer for online monitoring, detection and, especially, prediction of particular dynamic atmospheric phenomena such as precipitation and cloudiness is proposed in the paper. The ground-based microwave radiometer and meteorological stations were incorporated into the measurement campaign in order to observe and analyze actual brightness temperature changes. The characteristics of atmospheric parameters recorded over a period of 14 months were evaluated and new applications for rain forecasting and cloud detection, using specific features of signal variance, were proposed and validated.

The Evaluation of Total Radiation Q Based on Modal Aproach

  • DOI: 10.1109/EuCAP.2012.6205873
  • Odkaz: https://doi.org/10.1109/EuCAP.2012.6205873
  • Pracoviště: Katedra matematiky, Katedra elektromagnetického pole
  • Anotace:
    The total Q of selected structures is to be calculated from the set of eigenmodes with associated eigen-energies and eigen-powers. Thanks to the analytical expression of these quantities, the procedure is highly accurate, respecting arbitrary current densities flowing along the radiating device. The electric field integral equation, Delaunay triangulation, method of moments, Rao-Wilton-Glisson basis function and the theory of characteristic modes constitute the underlying theoretical background. Calculation of the modal energies and Q factors enable us to study the effect of the radiating shape separately to the feeding. To outline some benefits of proposed method, the total radiation Q of a Huyghens source is calculated for several distances between a loop and an dipole.

FSO Link Performance Modelling Using Artificial Intelligence

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This paper introduces an artificial neural network model created for weather influence evaluation of FSO link. Basic neural cluster analysis is performed and neural network model creation is discussed.

Landmine Detection Using Ground Penetrating Radar and Polarimetric Synthetic Aperture Radar

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    In this paper, the data processing based on polarimetric features extraction from Synthetic Aperture Radar (SAR) processed data is discussed. For this purpose, fully polarimetric data were collected using the ultra-wideband Ground Penetrating Radar (GPR) and quad ridged horn antenna. The measurement of plastic landmine, metallic pipe and rocks buried in the sand was carried out so that three dimensional data correction and visualization could be applied. Since the landmine is detected in the presence of a metallic target, a standard GPR processing does not lead to satisfactory results. Therefore, polarization and orientation features were obtained by means of the polarimetric decomposition in order to classify and detect various objects.

Power Balance of Inductive Wireless Power Transmission

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The analysis of power balance for concepts of wireless power transmission based on electromagnetic induction is performed in general way. The derivation of power transmission efficiency is shown. The conditions for maximal efficiency and maximal active power delivered to the appliance are found. The maximal efficiency is expressed as a function of single variable. The power balance for maximal efficiency and maximal active power delivered to the appliance is derived in terms of normalized active powers as functions of the same variable as maximal efficiency. The system input impedance is calculated.

Radiation Efficiency and Q Factor Study of Franklin Antenna Using the Theory of Characteristic Modes

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This paper presents the analysis of Franklin antenna by the Theory of Characteristic Modes. Modal radiation efficiencies are calculated and used to obtain the overall radiation efficiency. For each mode also the Q factor is calculated. On these results the influence of distance between arms of the folded part of antenna is demonstrated.

Software Tools for Efficient Generation, Modeling and Optimisation of Fractal Radiating Structures

  • DOI: 10.1049/iet-map.2010.0269
  • Odkaz: https://doi.org/10.1049/iet-map.2010.0269
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The paper describes in-house developed software tools for design of microstrip patch fractal antennas. As the fractal geometry is quite complex, IFSMaker application was developed purposedly for an easy maintaining of planar fractal structures. In the next step, we are using cavity model technique for modal analysis of internal fields of the patch. This simplified model is reasonably fast, so that optimisation loop may be employed in order to reduce the fundamental mode resonant frequency. This is accomplished with the valInFEM, PSOoptimizer and IFSLimiter applications. Theory of characteristic modes is then used to refine the results and finally antenna is simulated with full-wave CST simulator, built and measured.

Special Issue towards EuCAP 2012 "Emerging Materials, Methods, and Technologies in Antenna & Propagation"

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This special issue is composed of six extended papers originally published in Proceedings of EuCAP 2010. The common subject matter is the focus on emerging methods and technologies in antennas and propagation. Another selection criterion has been interdisciplinary of the presented research so that the research would preferably be also outside the scope of A&P topic. As a result we may provide you following themes: biomedical microwave and THz imaging, RF and THz identification technologies, statistical and deterministic modeling of electromagnetic wave propagation in indoor environment.

Wireless Power Transmission for Power Supply: State of Art

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The wireless power supply is motivated by simple and comfortable use of many small electric appliances with low power input. This paper reviews the concepts that are suitable for wireless power transmission with respect to power supply of such appliances in small areas. The categorization of the concepts is made. The efficiency of the concepts is discussed on general base. The reference levels for exposure to electric and magnetic fileds are mentioned, and maximal power delivered to an appliance by fulfillment of these levels is considered.

Advanced Modal Techniques for Microstrip Patch Antenna Analysis

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This paper shows the advantage of modal methods utilization in the area of microstrip patch antennas design. Namely, the Theory of Characteristic Modes (TCM) is developed starting from the Electric Field Integral Equation and formulating proper functional equation for stored and radiated power. Developed in-house TCM analyzer is presented and employed to investigate properties of the linearly and circularly polarized rectangular patch antenna.

Broadband Axial Excitation of Fabry-Perot Resonator

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The paper presents the broadband axial excitation of the Fabry-Perot resonator as well as its comparison with the standard radial excitation (via a dielectric foil) and two types of axial excitations (electric and inductive coupling) are discussed. The resonator was designed for the frequency range from 18 to at least 80 GHz. For the broadband measurement of the emission spectra, the excitation for the frequency range 18 - 26.5 GHz was proposed. Moreover, the excitations performance was measured and evaluated for the frequencies up to 40 GHz.

Heterodyne Detector for Absorption Microwave Spectroscopy

  • DOI: 10.1109/COMITE.2010.5481853
  • Odkaz: https://doi.org/10.1109/COMITE.2010.5481853
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The paper describes the heterodyne detector suitable for the microwave spectroscopy. At the lower frequencies (from the spectroscopic point of view), the measured gas is commonly saturated and the absorption measurement is impossible. The discussed heterodyne detector can measure with high dynamic range exceeding 90 dB. In addition, it enables to measure the weak signals or even very low changes in strong signals.

New Antenna Measurement System

  • DOI: 10.1109/COMITE.2010.5481719
  • Odkaz: https://doi.org/10.1109/COMITE.2010.5481719
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    A new antenna measurement system has been implemented in an antenna anechoic chamber at the Czech Technical University in Prague. The article contains the system overview, it brings the results of the first measurements and it shows the system improvements.

Possibilities of Wireless Power Supply

  • DOI: 10.1017/S1759078710000255
  • Odkaz: https://doi.org/10.1017/S1759078710000255
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This paper presents an overview of the principles suitable for wireless power supply of devices with a small power input in picocells. This means predominantly different types of small electric devices in the space of rooms. Basic principles, namely electromagnetic induction and electromagnetic wave, are explained using examples of developed systems. Different types of wireless power systems are compared with respect to efficiency, frequency, power, and transmission distance.

Simplified Fourier Transform Microwave Spectrometer

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The Fourier Transform Microwave Spectrometer (FTMW) is subject to simplification by means of the spectral analyser, instead of the super-heterodyne receiver. The paper is focused on the FTMW arrangement, the procedures of the resonator tuning and optimization of the excitation impulse length. In the paper, the virtues of the FTMW technique are demonstrated on the comparison of the emission and the absorption spectra.

The Wireless Power Supply with the Use of Coupling Surface

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This paper presents a part of a system for wireless power supply with the use of guided wave in the coupling surface. This system type is suitable for the supply of different devices with small power input in picocells. The main elements of the RF section of the system are slab dielectric waveguide which creates a coupling surface and adaptor to this waveguide. The text especially focuses on this adaptor which ensures the coupling of RF power to and from the slab dielectric waveguide.

Wideband Shorted Backfire Antenna with L-probe fed Microstrip Patch

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    In this contribution a novel configuration of highdirectivity broadband antenna is presented. Its main operational principle is based on the so-called "short backfire" (SBF) concept, however, instead of conventional dipole, rectangular microstrip patch is used as feeder.

Antenna Noise Temperature - Software Tools

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Designers of antennas and their associated components presently enjoy the convenience of performing fast, accurate, automated, design-related calculations due to the availability of a multitude of software "design tools" for modelling electromagnetic fields. Computations involved with specific problems such as antenna noise temperature, however, require supplementary software tools to augment the capability of these general purpose state-of-the-art professional programs. To adress this need, we have developed the "Antenna Noise Temperature Calculator" software program that utilizes either modeled or measured radiation patterns to calculate antenna noise performance parameters.

Quasioptical Beam Propagation for Remote Sensing

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    A development of millimeter waveband indoor sensors has brought new research challenges especially with respect to the sensing within complex environments. To investigate the propagation aspects for these systems the quasioptical approaches including Gaussian beams of basic and higher orders can be utilized. Difference between conventional and Gaussian beam based models can be significant especially for remote sensing systems being deployed within indoor scenarios. The paper discusses the advantages and drawback of these simulation approaches, based on measurement and analyses of electromagnetic wave propagation.

Route Diversity Simulations in Multi-HAP Networks during Heavy Rainstorms

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Route diversity is one of the available techniques to improve system availability of High Altitude Platform (HAP) networks during rainstorms. Route diversity was simulated in both time and space using radar rainfall data. The propagation aspects of HAP service as observed at the user ground station were analyzed based on their analogy to terrestrial point-to-multipoint systems.

The use of the Fabry-Perot interferometer for high resolution microwave spectroscopy

  • DOI: 10.1016/j.jms.2009.03.015
  • Odkaz: https://doi.org/10.1016/j.jms.2009.03.015
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    A simple Fabry-Perot interferometer was used for measurements of microwave spectra. Both basic experimental arrangements, absorption and emission, were tested on the rotational spectra of acetonitrile. The interferometric results obtained were compared with the spectra measured using a standard high resolution microwave spectrometer.

UWB Dipole Antenna Optimization with Neural Network Tuned Algorithm

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This paper describes an improved approach in an optimization of different UWB dipole antennas. The new procedure of tuning different optimization algorithms is presented. Fine-tuning of optimizing algorithm which is not elementary problem is discussed.

Validation of Route Diversity Schemes of Two Joint HAP LInks

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    High Altitude Platforms (HAP) can bring a possibility of a very fast additional coverage e.g. in the case of catastrophes, when existing networks collapse, or could be utilised as alternatives to satellite or terrestrial systems. In this paper electromagnetic wave propagation aspects for HAP systems are discussed. In the first part, atmospheric gas attenuation for inter-HAP links is determined. Next part of the paper deals with the influence of rain on millimetre wavelength links between user stations and High Altitude Platform. Typical route diversity scheme given by the recommendation ITU-R P. 618 used for satellite links cannot be accurately applied. Based on simulation results HAPs are analyzed and particular corrections for the Czech Republic are proposed.

A Study of Gas and Rain Propagation Effects at 48GHz for HAP Scenarios

  • DOI: 10.1155/2008/734216
  • Odkaz: https://doi.org/10.1155/2008/734216
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The atmosphere and rainfall significantly limit the performance of millimeter wave links and this has to be taken into account, particularly, during planning of high altitude platform (HAP) networks. This paper presents results from the measurement and simulation of these phenomena. A simulation tool from our previous analyses of terrestrial point-to-multipoint systems has been modified for HAP systems. Based on a rainfall radar database and gas attenuation characteristics as measured by a Fabry-Perot resonator, the performance of a simple link, two-branch diversity links, and more complicated HAP scenarios are discussed.

Dielectric Lens Utilization for Fabry-Perot Resonator Optimal Coupling

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This paper introduces the Fabry-Perot resonator designed for the frequency band 18-80 GHz. The Fabry-Perot improvement using a hyperbolical lens, which transforms the spherical wave, radiated by the standard horn antennas to the plane wave irradiating the coupling foil of the resonator is discussed. This approach helps to efficiently couple the energy into and out of the resonator. The quality factors (loaded as well as unloaded) were evaluated from the measured frequency responses of the resonances. These quality factors show the effectiveness of used lenses and functionality of the resonator within the frequency band 75-110 GHz, which is higher than the designed band.

Distortion Minimization of Radiated Impulses of Tapered Slot Vivaldi Antenna for UWB Application

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The paper deals with the optimization of the Vivaldi antenna, which is suitable for the measurement of impulse radiation characteristics. In case of particular ultra wideband applications (i.e. radar, positioning, etc.), it is crucial to know the transient responses of antennas. The optimization process searches for the Vivaldi antenna shape. The optimization accomplishes three required parameters - good matching, minimal distortion and smaller antenna dimensions. The parametric study and the manual step-by-step method were used in the process of antenna optimization. The main part of the paper presents the impulse distortion minimization by the feeding transition and the overall obtained results, which are compared with the measured characteristics.

Evaluation and Correction of Cable Phase Stability in High Frequency Near-Field Measurement

  • DOI: 10.1109/COMITE.2008.4569887
  • Odkaz: https://doi.org/10.1109/COMITE.2008.4569887
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    In case of the near-field measurement, the radiated field by the measured antenna is received by two-dimensional scanner in defined points. During the process of the field scanning, the cable between the VNA and the scanner antenna is moved and its parameters are changed. This paper deals with the evaluation of the cable parameters changes. The dominant change is represented by the phase deviation of the cable transmission coefficient.The paper also proposes the method of the cable errors correction and evaluation of the correction method efficiency. The correction can be based on the full calibration at the reference plane of the scanner antenna feeding in all points of scanned field. The aforementioned approach is more time consuming than the proposed method, where the full calibration is performed in one selected point, while the correction of the cable parameters is based on the estimation based on the input impedance of the cable loaded by the scanner antenna.

Full-Wave Modeling of Fabry-Perot Resonator in Millimeter Waves

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    One of two numerical principles on dielectric materials in connection with Multi Level Fast Multipole Method (MLFMM) and Uniform Theory of Diffraction (UTD) approximation of Method of Moments (MoM) have to be applied to analyze electrically large structures at higher frequencies. The paper deals with a development and comparison of several models of Fabry-Perot resonator for spectroscopic measurement of both gas attenuation and spontaneous emission. A simplified model capable to solve the resonator performance up to 110 GHz (i.e. the radius of the mirrors corresponding to 55 times wavelength) is introduced.

Higher Modes of Sub-millimetric Fabry-Perot Resonator

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The atmospheric attenuation is very often neglected within propagation of electromagnetic waves at lower frequencies but it has significant effects on millimeter, sub-millimeter and terahertz links. Based on a previous measurement campaign, this paper presents results from simulation of the Fabry-Perot resonator utilized for the gas attenuation measurements. The gas attenuation has proved to be highly influenced by higher modes arising from the resonator cavity. Their dependence on particular measurement deployment is analyzed in the paper.

PMP System Analyzing Based on Rain Spatial Model

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Signal propagation at frequencies above 10 GHz suffers from significant attenuation due to rain. Given the non-uniform spatial distribution of the rain rate, the route diversity concept can be utilized to plan point-to-multipoint (PMP) systems. Outages within systems were studied using space-time simulations of PMP under specific conditions. PMP system performance was analyzed based on the rain spatial parameter and on a derived system outage improvement probability.

Gas Attenutation Measurement by Utilization of Fabry-Perot Resonator

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The atmosphere significantly limits the performance of millimetre-wave and terahertz systems. The aim of this paper is to introduce a development and an improvement of Fabry-Perot resonator utilized especially for gas attenuation measurements. The measurement setup and results from simulations and laboratory measurements performed via Fabry-Perot resonator are discussed as well.

Measurement Methods of Impulse Radiation Characteristics for Ultra Wideband Antennas

  • DOI: 10.1049/ic.2007.0929
  • Odkaz: https://doi.org/10.1049/ic.2007.0929
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The principal aim of the paper is to introduce results of measurements methods performed in the frequency domain as well as in the time domain. The aforementioned methods are based on the measured data processing that is carried out by means of the measured transmission coefficient between two antennas. Moreover, the additional aim of the paper is to present the differences between various and several approaches (in both domains).

Microstrip Patch Antennas with Specific Properties: Multi-band, Miniaturized, and Gain Enhanced

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The paper deals with the microstrip patch antennas with specific properties that are based on re-arrangement of current densities on their surface by means of geometrical modifications. Selected types of multi-band patches with edge perturbation elements, electrically miniature fractal and gain enhanced collinear patches are presented. Description of the physical behavior via surface current distribution, as well as used design approaches are done.

Modal Analysis of Miniature Microstrip Patch Antennas Based on Fractal Geometry

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Paper deals with modal analysis of electrically small patch antennas. Cavity model and the Theory of characteristic modes are used for analysis, one sample is simulated with CST Microwave Studio also.

Optimization of Beam Focusing Into the Stark´s Cell for MM-Wave Spectroscopy

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This paper presents an analysis of the power distribution behind dielectric lens and optimization of the beam focusing by double sided dielectric lens into the Stark´s cell as a particular part of spectroscopic measuring equipment.

Optimization of Tapered Slot Vivaldi Antenna for UWB Application

  • Autoři: Černý, P., Nevrlý, J., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Conference Proceedings - ICECom 2007. Zagreb: KoREMA, 2007. p. 217-220. ISBN 978-953-6037-50-6.
  • Rok: 2007
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The optimization process searches fot the Vivaldi antenna shape. The parametric study and the manual step-by-step method were used in the process of antenna optimization - good matching, minimal distortion. Obtained results were compared with measured characteristic.

Optimization of Transient Response Radiation of Printed Ultra Wideband Dipole Antennas (Using Particle Swarm Optimization Method)

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    In case of particular ultra wideband applications (i.e. radar, positioning, etc.), it is crucial to know the transient responses of antennas. In the first part of the paper, the optimization process searches for the dipole shape that accomplishes two required parameters i.e. a good matching and minimal distortion. The particle swarm optimization method was used in the process of the dipole shape optimization. As a result, the optimized ultra wideband dipole is perfectly matched. Moreover, it minimally distorsts the applied signal. The second apart of the paper discusses the influence of the feeding circuit on radiating parameters and on the dipole antenna matching.

Planar UWB Dipole Antennas Optimization Using PSO Method

  • Autoři: Černý, P., Nevrlý, J., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Proceeding of the 2nd European Conference on Antennas and Propagation. Stevenage, Herts: The Institution of Engineering and Technology (IET), 2007. ISBN 978-0-86341-842-6.
  • Rok: 2007
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The paper discusses the dipole antenna optimization procedure. The first part is focused on the choice of the fitness function in order to optimize the ultra wideband dipóle antennas for impulse radiation, especially for minimization of the radiated impulse distortion and reduction of antenna reflections. The second part deals with the implementation and improvements of the Particle Swarm Optimization method (PSO). The number of swarms is extended in order to reach better global maximum seeking. The parallelization of the solved tasks (particles) is used during the optimization process. The comparison of the classical and improved PSO method is presented. The final part presents the obtained results of unique optimized dipole shapes with basic wideband dipoles. The obtained parameters and characteristics are also presented.

Radiation Characteristics of Optimized Ultra Wideband Printed Dipoles for Different Impulse Excitations

  • Autoři: Černý, P., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: PIERS 2007 Prague - Proceeding of Progress In Electromagnetics Research Symposium. Cambridge, MA: The Electromagnetics Academy, 2007. ISSN 1559-9450. ISBN 978-1-934142-02-8.
  • Rok: 2007
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    In case of particular ultra wideband applications (i.e. radar, positioning, etc.), it is crucial to know the transient responses of antennas. This paper picks up the threads of the previous work [4], where the particle swarm optimization method searches for the dipole shape, which accomplishes two required parameters - good matching and minimal distortion. As a result, the optimized ultra wideband dipole is perfectly matched and minimally distorts the applied signal. The main part of the paper presents the transient radiation characteristics of optimized dipoles with common dipole element shape, such as the ideal dipole, dipole with balun transformer and monompole with planar ground plane. A particular attention is paid to the different impulse excitation. The spatial distributions of the fidelity and the spatially averaged fidelity is prented for three different excitation Gaussian signals.

Septum Horn Antennas at 47/48 GHz for High Altitude Platform Stations

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    A design of a septum horn antenna for frequency band 47.0-48.5 GHz (based on the studies and designs at 1.3 GHz and 2.4 GHz) left and right polarized is presented. A 20 dBi gain septum horn antenna was developed and manufactured. Calculated data (radiation pattern, beamwidth, sidelobes suppression, gain and VSWR) were compared with measured data.

Shielding Effectiveness Measurement of Small Enclosures Using Linearly and Circularly Polarized Antennas

  • DOI: 10.1049/ic.2007.0971
  • Odkaz: https://doi.org/10.1049/ic.2007.0971
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This paper describes the special EMC issue which emerges during shielding effectiveness measurement of relatively (compare to the wavelength) small enclosures. The main aim of this paper is to show difference of the shielding effectiveness values in dependence on different types of used measuring linearly and circularly polarized antennas.

Simulated Transient Radiation Characteristics of Optimized Ultra Wideband Printed Dipole Antennas

  • Autoři: Černý, P., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Proceedings of 17th International Conference Radioelektronika 2007. Brno: FEKT VUT v Brně, 2007. pp. 575-580. ISBN 978-1-4244-0821-4.
  • Rok: 2007
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    In case of particular ultra wideband applications (i.e. radar, positioning, etc.), it is crucial to know the transient responses of antennas. This paper picks up the threads of the previous work [5], where the optimization process searches for the dipole shape, which complishes two required parameters - good matching and minimal distortion. The particle swarm optimization method was used in the process of dipole shape optimization. As a result, the optimized ultra wideband dipole is perfectly matched and minimally distorts the applied signal. The main part of the paper presents the transient radiation characteristics of optimized dipoles with common dipole element shape, such as the ideal dipole, dipole with balun transformer and monopole with planar ground plane.

The European School of Antennas: Results and Perspectives

  • Autoři: Maci, S., Lindmark, B., Freni, A., Breinbjerg, O., Raisanen, A., Laheurte, J.-M., Mahdjoubi, K., Frezza, F., Vecchi, G., Jofre, L., Sierra Perez, M., Ferrando, M., Kildal, P.S., Skrivervik, A., Gerini, G., Dubard, J.L., Casali, B., Manteuffel, D., Bucci, O., Wiesbeck, W., prof. Ing. Miloš Mazánek, CSc., Sipus, Z., Hall, P., Ibars, C.
  • Publikace: Proceeding of the 2nd European Conference on Antennas and Propagation. Stevenage, Herts: The Institution of Engineering and Technology (IET), 2007. ISBN 978-0-86341-842-6.
  • Rok: 2007
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The European School of Antennas (ESoA) is a new model of geographically-distributed school that has the objecitve to reinforce the European training and research in antennas and relevant applications. This paper presents the objective and perspectives of ESoA and the results obtained in 2006 and the first part of 2007 in terms of flow of students and teachers.

Theory of Characteristic Modes and its Applications for Analysis of Fractal Microstrip Patch Antennas

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The paper deals with the fractal microstrip patch antennas with specific properties based on special fractal geometrical modifications. Desctiption of physical behavior via surface current distribution is discussed. Different modal analysis approaches (Cavity model and the Theory of characteristic modes) as well as full-wave EM tools have been used for the simulations.

Theory of Characteristic Modes: Getting More Insight into Linear Antenna Behavior

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The Theory of Characteristic Modes is a very useful tool to get physical insight into antenna behavior. It is possible to easily obtain resonant frequencies, modal radiation Q or bandwidth, modal currents and modal radiation patterns. The paper is intended to study well known linear antennas under this new point of view.

Wideband Rectangular Microstrip Patch Antenna

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Paper focuses on so-called L-probe feeding technique suitable for wideband (<30% relative band-width) driving of microstrip patch antennas. Physical explanation, simulation and measurement are presented. Further modification for improvement of radiation characteristic is also proposed.

A Self-Complementary 1.2 to 40 GHz Spiral Antenna with Impedance Matching

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This paper describes a design of the Self-Complementary Spiral Antenna (SCSA) with consists of a spiral antenna and wideband impedance transformer. The spiral antenna and the transformer are designed separately due to computing demands. New knowledge about current distribution on the spiral antenna and influence of higher numbers of wavelength in circumference is presented. The novel transition between feeding and radiating antenna structure are optimized in the frequency range 1.2 to 40 GHz. The meaning of the transition in the paper includes the impedance as well as the geometry transforming of the structure. The antenna is suitable for wideband illuminating of a parabolic reflector due to relatively constant phase center and radiation pattern with frequency.

Activities in ACE WP 2.3-1 on Wideband and Multiband Radiators

  • Autoři: Bonnedal, M., Angelopoulos, E., Antonino, E., Balling, P., Chan, K., Erickson, R., Lager, I., prof. Ing. Miloš Mazánek, CSc., Sorgel, W., Ubeda, E., Yarovoy, A.
  • Publikace: Proceedings of The European Conference on Antennas and Propagation: EuCAP 2006. Noordwijk: ESA Publications Division, 2006. ISSN 1609-042X. ISBN 92-9092-937-5.
  • Rok: 2006
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Developments in wireless communications and sensing require increasing wider frequency bands and that multiple functions can be provided by single antenna systems. This paper presents an overview of the activities of ACE work package 2.3-1, intended to gather and integrate expertise on a European level. We review here the progress of the partners and relate the work to other ACE activities.

Dependence of Area-Averaged Rain Rate on PMP System Coverage Planning

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    In this paper, area-averaged rain rate calculation using the ITU-R statistical model is discussed and its accuracy investigated. The influence of its proper determination on the coverage planning of PMP systems is revealed. Moreover, a model modification which better fits the local conditions prevailing in the Czech Republic is provided.

Double Ridged Structures Mode Study for Broadband Antennas Design

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Knowledge of the cutoff frequencies of modes in nonstandard double ridged waveguides is extremely important for determination of operation bandwidth for design of broadband structures. It is shown that for nonstandard dimensions of the ridged waveguide the TE30 mode doesn't exist or is degenerated or the higher mode skips the TE30 mode. Strategy of the complex broadband double ridged horn antennas design (coaxial - waveguide transitions, impedance transformers, radiated ridged and horn structures etc.) is mentioned and as an example the 4-40GHz antenna is presented.

Education in Antennas, Wave Propagation and Microwaves

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The paper is focused on teaching of "applied microwaves". Attentions is turned to antennas, but the same structure of education process is possible to apply for e.g. radio-wave propagation, microwaves, EMC, and other "electromagnetic topics" in their whole. The structure of the education is based on the appropriate amount of the theory followed by the computer simulations, the theoretical and engineering design and development, the measurement and final evaluation, which acts as the feedback between the initial goals and the final results. Important role of laboratory experiments based on flexible experimental set-ups is introduced and the possibility of distant (internet) laboratory excess is mentioned.

L-System Tool for Generating Fractal Antenna Structures with Ability to Export into EM Simulators

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    An L-System (Lindenmayer system) is a scheme primarily developed in the area of the computer science for simulating the development of biological structures. It has also been found very useful for generating the geometry of various fractal antennas. A Matlab environment has been used for both implementing an in-plane L-systems algorithm and for creating appropriate files for widely used EM simulators like the IE3D and the CST Microwave Studio. Sinally, the performance of the developed script is demonstrated on two fractal microstrip patch antennas.

Measurement of Shielding Effectiveness of Small Enclosures

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The evaluation of the Shielding Effectiveness (SE) brings great challenges from the EMC measurement point of view. Particularly in the case of measurement of small enclosures, many different approaches can be used. Therefore, based on an extensive measurement campaign, various aspects of measurement of the shielding effectiveness of small metallic enclosures were investigated. Significant results of this campaign are discussed in this paper.

Miniature Microstrip Fractal Patch Antenna Working with Crossed-Diagonal Mode

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Paper describes a novel type of miniature microstrip patch antenna based on fractal geometry. Miniature properties are achieved by the presence of unusual fundamental resonant mode which we call "crossed-diagonal" (CD) current.

Modeling in Education of Antennas

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The paper is focused on the key role of modeling in education process in the field of antennas. Attention is turned not only to the modeling, but to the whole structure of education. Depending on the level of study, the balanced structure of the education is based on the appropriate amount of the theory followed by the computer simulations, the theoretical and engineering design and development, the measurement and final evaluation, which acts as the feedback between the initial goals and the final results.

Optimalization of the Septum Polarizer Feed for 1.296 GHz EME

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    We describe the reduction of polarization losses and other optimizations in the design of a septum polarizer antenna feed configured in a circular waveguide. The goal is to improve the overall efficiency of a parabolic dish antenna system which will be used for EME (Earth-Moon-Earth) microwave communication.

Spiral Notch Perturbation Element Concept for the Design of Multiband Quarterwavelength Patch Antennas

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Quarterwavelenght patch antenna loaded by one to three pairs of spiral notches has been used to reach dual to quadband performance. Physical insight on multiband behavior is done via description of vector surface current distribution at individual resonant frequencies acquired by EM simulator IE3D. The used principle has been verified by measurement on the dualband prototype. The method can been generalized as the use of perturbation elements in the patch motif to excite suitable higher order modes to reach multiband performance of the studied antenna.

Transient Response Optimization of Ultra Wideband Antennas (Using Particle Swarm Optimization)

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    For some ultra wideband applications (i.e. radar, positioning, etc.), it is crucial to know the transient responses of antennas. Optimization process searches for the dipole shape, which accomplishes two required parameters - namely good matching and minimal distortion. The dipoles have derivative characteristics. The distortion is evaluated from the derivative of the excitation impulse with the radiated impulse. The particle swarm optimization method was used in the process of optimization. This method was implemented in MATLAB(R), where the antenna structure is generated. The antenna is ubsequently simulated in the CST Microwave Studio(R). The optimized ultra wideband dipole is perfectly matched and minimally distorts the applied signal.

Ultra Wideband Dipole Antenna Optimization

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This paper describes optimization of the palanar ultra wideband dipole antennas, which are optimized for perfect matching and perfect impulse radiation characteristics. The optimization of the dipole shapes starts from the classical wideband dipoles, expecially from elliptical and diamond shapes. These wideband dipoles have been analyzed and optimized with unsatisfactory parameters performance. This paper proposes two optimized dipole structures fulfiling required parameters. Designed antennas could be used as an impulse-shaping filter for forming of transmitted UWB impulse.

Wideband and Multiband Radiator Activities

  • Autoři: Bonnedal, M., Angelopoulos, E., Antonino, E., Balling, P., Chan, K., Erickson, R., Lager, I., prof. Ing. Miloš Mazánek, CSc., Sorgel, W., Ubeda, E., Yarovoy, A.
  • Publikace: Proceedings of The European Conference on Antennas and Propagation: EuCAP 2006. Noordwijk: ESA Publications Division, 2006. ISSN 1609-042X. ISBN 92-9092-937-5.
  • Rok: 2006
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Activities of working group for broadband and multiband antennas in a frame Antenna Centre of Excellence are mentioned.

Wideband Measurement in a Small Shielded Box Using Equiangular Spiral Antennas

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Small shielded boxes are nowadays widely used for measurement of EMS, EMI and sensitivity properties of different devices. This paper deals with an improvement of commercial small shielded box parameters for a measurement of sensitivity of small mobile devices in 650 MHz - 4 GHz frequency band. Optimization of shielded box parameters is obtained by an inner area modification. Suitable wideband equiangular spiral antenna was designed for this measurement. Parameters of antenna inside the box, such as gain, impedance, directivity etc. are discussed in the paper. Effects of antenna positions in the box for a transmission are shown and the best configuration of antennas placing for the transmission in the shielded box is chosen.

A Key Role of Simulation in New Approach to Electromagnetics Education

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The paper describes the examples in teaching electromagnetics at the Czech Technical University in Prague. Due to the abstract nature of electromagnetics, computer simulations play an important role here. The paper describes the way of the efficient incorporation of simulations to the teaching process. We emphasize the simulations have to be deeply analyzed together with students to improve their inderstanding of the physical matter of electromagnetic phenomena.

CAD/CAM ve výuce předmětů katedry elektromagnetického pole FEL - ČVUT v Praze

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    V článku je popsáno použití nástrojů CAD/CAM pro výuku na katedře elektromagnetického pole FEL ČVUT v Praze. Katedra disponuje několika softwarovými produkty, které jsou v současné době považovány za nejvyspělejší a jsou schopny simulovat komplexně elektromagnetické problémy. Nejdůležitější simulátory jsou zde popsány současně s jejich pedagogickým využitím.

Collinear Microstrip Patch Antenna

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Paper deal with a novel type of so called collinear types of antennas realized in microstrip antenna technology. Principle of operation is in excitation of TM0x modes of patch antenna where x is odd number that stands for the number of resonant half current wavelength. Perturbation elements in the shape of lateral slots are placed in the structure of the patch in such a way that they eliminate radiation from even half current wavelengths. Resulting (x+1)/2 in-phase source areas ensure broadside radiation. Prototype of the antenna for frequency band 869 MHz has been realized and measured.

Education in Antennas, Wave Propagation and Microwave Techniques

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The paper is focused on teachnig "applied microwaves". Attention is turned to antennas, wave propagation, microwaves and EMC. The structure of the education based on the theory followed by the computer simulations is described. A mutual cohesion between engineering, design, numerical methods, CAD is mentioned.

Elliptical Dipole Antenna for UWB

  • Autoři: Černý, P., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Radioelektronika 2005 - Conference Proceedings. Brno: VUT v Brně, FEI, Ústav radioelektroniky, 2005. pp. 207-210. ISBN 80-214-2904-6.
  • Rok: 2005
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This paper describes the planar ultra wideband (UWB) dipole antenna that uses elliptical elements. The designed antenna could be used as a pulse shaping filter for forming of transmitted UWB pulse or as a signal matched filter in the receiver.

Improvement of Parameters of Broadband Antenna Structures

  • Autoři: prof. Ing. Miloš Mazánek, CSc., Hradecký, Z., Černý, P., Piksa, P.
  • Publikace: Proceedings - ISAP 2005. Seoul: Korea Institute of Electromagnetic Engineering and Society (KIEES), 2005. pp. 997-1000. ISBN 89-86522-76-4.
  • Rok: 2005
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Different broadband antennas are well known for a long time, e.g. Vivaldi structures, double ridged horn antennas, log-spiral, helical antennas, elliptical dipoles etc. New parameters of the design for using of broadband antennas in new measurement systems (e.g. EMC) and services and ideas how to reach them, demands, and design of a new parts of antenna structures are described. All antennas of improved parameters here listed were developed and tested at the Czech Technical University and National Security Authority in Prague.

Measurement of a Shielding Effectiveness of Relatively Small Metallic Enclosures

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Paper presents several results of the study and experimental verification of a shielding effectiveness of relatively small metallic enclosures, which operate above the first resonance. There is no standard for measurement and therefore different aspects of measurement and methodology are discussed. Relative size, volume, quality factor of the enclosure, position, radiator type, reciprocity etc. are discussed.

Miniature Microstrip Fractal Patch Antenna FED by J-Probe

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The paper describes a novel kind of miniature fractal microstrip patch antenna based on the Inverted koch Square fractal. Tuning possibilities were extended by using the J-probe with more degrees of freedom compared to a conventional L-probe. A parametric study was performed using a full-wave simulator IE3D.

Nonstandard Double Ridged Waveguide Mode Study

  • Autoři: Hradecký, Z., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Radioelektronika 2005 - Conference Proceedings. Brno: VUT v Brně, FEI, Ústav radioelektroniky, 2005. pp. 346-349. ISBN 80-214-2904-6.
  • Rok: 2005
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Knowledge of modes cutoff wavelengths in double ridged waveguides is highly demanded for determination of operation bandwidth and for the other purposes. In the paper a study of double ridged waveguide modes is presented. The main focus is given to analysis of nonstandard waveguide dimensions that is used for antenna design.

Normalized Site Attenuation (NSA) Measurement

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Normalized site attenuation testing (NSA) is the process to evaluate the quality of test site for EMC testing. The standard EMC measurement uses the NSA in the frequency range 30 MHz - 1 GHz. It is supposed the use of higher frequencies for EMC measurement in a near future, where the measurement of wall reflections is usually recommended for site testing. Experiences based on the measurement of NSA, the antennas and its calibration (antenna factor), polarization and geometry of measurement and parasitic influence of floor reflections are mentioned in the paper. Problems of EMC test sites are also discussed with pedagogical aspects from point of view Electromagnetic Field Theory and its simulation tools.

Optimized Ultra Wideband Dipole Antenna

  • Autoři: Černý, P., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: ICECom 2005 - Conference Proceedings 18th International Conference on Applied Electromagneics and Communications. Dubrovnik: IEEE Croatia Section, 2005. p. 549-552. ISBN 953-6037-44-0.
  • Rok: 2005
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This paper describes optimization of the planar ultra wideband dipole antennas, which are optimized for perfect matching and perfect impulse radiation chracteristics. Paper proposes two optimized dipole structures fulfilling required parameters.

Radiated Impulse Measurement of Ultra Wideband Monopole Antennas

  • Autoři: Černý, P., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: The 13th Conference on Microwave Techniques - COMITE 2005. Praha: IEEE Czechoslovakia Section, 2005. pp. 267-270. ISBN 80-86582-16-7.
  • Rok: 2005
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Paper desribes the new method of solving radiated impulses by ultra wideband antennas from the frequency domain measurement. An elliptical dipole was used as a reprentative of UWB antenna. Simulated characteristics are compared with solved results based on measurement.

Radiated Near-Field Measurement - Vegetation Scattering

  • Autoři: prof. Ing. Pavel Pechač, Ph.D., Lédl, P., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Proceedings of the International Conference on Electromagnetic Near-Field Characterization and Imaging. Barcelona: International Center for Numerical Methods in Engineering (CIMNE), 2005. pp. 187-192. ISBN 84-95999-72-2.
  • Rok: 2005
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Power balance and fading statistics are very important issues for advanced point-to-multipoint wideband communication systems operating in millimeter waveband. Since the typical environment is an urban and suburban area a vegetation blockage is one of the performance limiting factors. While the average attenuation caused by trees is dealt with for many years there are not many resources concerning the dynamics effects caused by the vegetation blockage - fast fading statistics, etc. The goal of the presented laboratory experiment was to define basic parameters of a theoretical model. To obtain well defined conditions a radiated near-field scattered by a tree under test was measured using a near-field scanner at 38 GHz. The first phase, measurement of the co-polar field component in a 2D reception plane for various tree types and wind conditions, is introduced. The measurement data were used for the modeling of dynamic effects caused by vegetation obstacles.

Rain Dependant Site Diversity Outage Improvements Statistics for Systems Working in Millimeter-Wave Band

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The signal propagation at the frequencies above 10 GHz suffers from significant attenuation due to rain, which in case of point-to-multipoint systems is unlikely to be compensated for by available fade margin alone. For this reason and especially thanks to the non-uniform spatial distribution of the rain rate, it is suitable to utilize site diversity concept during planning of point-to-multipoint wireless systems. A database of radar data for numerous types of rain events has been established to enable system testing under different conditions. Outage improvement was studied using space-time simulations of point-to-multipoint systems in a specific area under a specific rain conditions. System outage improvement probability was derived as a straightforward function of the rain fade margin, angle separation and distances of main and diversity hubs. Some of the simulation results at 42 GHz and corresponding outage improvement probability using the site diversity are presented as well.

Shielding Effectiveness Measurement Issues for Small Enclosures

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Shielding Effectiveness (SE) is one of the major aspects of any EMC design process. In this paper, a detailed analysis of measurement issues of a shielding effectiveness of relatively small metallic enclosures is presented. An extensive measurement campaign has been done to investigate various aspects of measurement of the small enclosures shielding effectiveness.

Shielding Efficiency Measurement Possibilites

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Knowledge of shielding efficiency of plane materials like shielding panels, special paints, windows foils etc. is demanded for construction of shielded boxes, enclosures and for other applications. Shielding efficiency is possible to measure in free space or in waveguide. Measurement in free space was performed in divided anechoic chamber by wall with window there are placed measured materials. Waveguide measurement unit was specially designed and manufactured to measure the high level of shielding efficiency of thin conductive materials in the frequency band of about 400 MHz. The shielding efficiency of various materials was measured by means of both methods and the results were compared. At the end is discussion about advantages and disadvantage various methods.

The Miniature Fractal Patch Antenna

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    In this work we study novel kind of miniature and broadband fractal patch antenna based on Inverted Koch Square Fractal with variable indentation angle. L-System generator was advantageously used to create desired geometry with possibility of adjusting its properties. Impedance and radiation behavior of proposed antennas are numerically studied with IE3D MoM simulator and partially by modal analysis as well.

The Miniature Inverted Koch Square Microstrip Patch Antenna

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Novel kind of miniature and broadband fractal patch antenna based on inverted Koch square fractal with variable indentation angle is studied. L-System generator was advantageously used to create desired geometry with possibility of adjusting its properties. Impedance and radiation behavior of proposed antennas are numerically investigated with IE3D MoM simulator and partially by modal analysis as well.

Vzdělávání v elektromagnetismu na rozcestí

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    V příspěvku je diskutována současná úloha výuky elektromagnetismu na elektrotechnických fakultách. Je zmíněno použití elektromagnetických simulátorů ve výuce a popsán praktický struktorovaný příklad výuky na popisu vyzařování liniového zářiče.

Zobecněný přístup k měření v mikrovlnné oblasti

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Je popsán obecný princip měření jak v časové, tak ve frekvenční oblasti a vzájemné vazby jednotlivých parametrů.

Anténní laboratoř s bezodrazovou komorou

  • Autoři: prof. Ing. Miloš Mazánek, CSc., Bártík, H.
  • Publikace: Sborník vzdělávacích a vědeckovýzkumných činností a nabídek. Praha: IEEE Czechoslovakia Section, 2004. pp. 22-23. ISBN 80-86582-15-9.
  • Rok: 2004
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    V příspěvku je popsána anténní laboratoř včetně implementovaných měřicích metod pro měření antén a rušivého elektromagnetického vyzařování.

Building Electrical Parameters Estimation

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    An accuracy of all empirical and semi-empirical models for signal coverage prediction especially in an indoor environment significantly depends on precise input parameters. These parameters include the information on electrical material parameter (permittivity, permeability, conductivity) as well as geometry of the walls. Because the building wall structure is usually a complicated pla-parallel layered media, there is not possibility to predict these based from single frequency and only scalar measurement. Wideband - or multi-band measurement can improve the tuning of the model better to the reality. A method which helps to estimation the dielectric parameters and also wall insertion loss from such wideband measurement is introduced.

Education in Antennas - Phased Antenna Arrays

  • Autoři: Černý, P., prof. Ing. Miloš Mazánek, CSc., Mrkvica, J.
  • Publikace: Proceedings of Workshop 2004. Praha: České vysoké učení technické v Praze, 2004. pp. 436-437. ISBN 80-01-02945-X.
  • Rok: 2004
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The paper describes the tasks created for teaching phased antenna arrays. They are included in antenna theory subjects. The first two tasks are aimed at the current distribution influence (amplitudes and phases of the currents), while the following two tasks are aimed at the used radiating elements influence (element placement and element parameters - radiation patterns). This paper also discusses the following principles of the education: current distribution determines all antenna parameters, difference between the antenna and the antenna array, connection of the simulation and the practical experiment.

Influence of Horizontally Variable Refractive Index Height Profile on Tropospheric Refraction

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Tropospheric refraction effects are discussed here, with an aim at inspecting an influence of change of refractive index profile with distance to a terrestrial millimetre link. When treating refraction effects in the troposphere, usually only height dependence of the refractive index profile is considered. However, this might not always be exactly the real situation. Situation may occur, that electromagnetic wave is exposed to range dependent refractive index height profiles as it propagates. Several examples are presented here with results in terms of received signal strength and angle of arrival. Under certain refractive index distribution the electromagnetic wave can propagate at a long distance, exceeding the optical line-of-sight distance of the terrestrial link and possibly resulting in interference effects.

LABLINK: A Study and Examples of Remote Internet Based Real Time Engineering Laboratories

  • Autoři: Katebi, R., Merckx, D., Berger, U., prof. Ing. Miloš Mazánek, CSc., Tichon, J., Georgiev, G., Baltrušaitis, P., Smet, E., Figwer, J., Cathoor, R.
  • Publikace: 2nd IFAC Workshop on Internet Based Control Education 2004. Grenoble: Laboratoire d'Automatique de Grenoble, 2004.
  • Rok: 2004
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This paper describes the results of collaboration of nine European Universities to develop remote laboratory experiments for teaching and training (LABLINK Project). The project was supported by the SOCRATES Minerva Programme. The main goal was to investigate the technical and educational requirements and implications of using such technology for teaching. The project was innovative in both the technical and pedagogical sense in that appropriate teaching, and learning methodologies were being studied. The target group consisted of undergraduate and postgraduate students as well as engineers in industry. This paper concentrates only on technical study of the remote labs. Further information can be obtained from the Lablink Web page: http://www.lablink.be.

Measurement of Diffraction on Dielectric Building Materials to Improve the Remote Sensing Data Evaluation

Modeling and Measurement of Dynamic Vegetation Effects at 38 GHz

Návrh a vývoj antén

On the Modal Anylsis of Fractal Microstrip Patch Antennas

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Full wave simulation of complex structures presented by fractal microstrip patches is very difficult and time-consuming. Cavity model has been found to be very useful and fast in obtaining basic parameters of such structures like resonant frequencies, field distribution and radiation pattern. Comparison with full-wave simulation results to reliable agreement.

Planar Patch Antennas with Fractal Boundary

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This paper describes an innovative approach for the simulation of the microstrip patch antennas with fractal boundary. First, L-System based fractal generator with the possibility of exporting the desired geometry into various EM simulators has been developed. Before the full-wave simulation is performed, modal analysis to predict the resonant frequencies, field distribution and radiation pattern is employed.

Shielding Effectiveness of a Relatively Small Metallic Enclosure

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    This paper present several results of the study and experimental verification of a shielding effectiveness of relatively small metallic enclosures, which operates above the first resonance. Different aspects of measurement and methodology are discussed - including relative size, volume, quality factor of the enclosure, position and radiator type, reciprocity measurement etc.

Shielding Efficiency Waveguide Measurements at 400 MHz

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Knowledge of shielding efficiency of plane materials like shielding panels, special paints, windows foils etc. is demanded for construction of shielded boxes, enclosures and for other applications. Waveguide measurement unit was specially designed and manufactured to measure the high level of shielding efficiency of thin conductive materials in the frequency band of 40 MHz. Dynamic range of measurement up to 100 dB was reached. Shielding efficiency of various materials was measured and compared to measurements in free space. The waveguide unit development brought several advantages which had to be addressed. The main problems were caused by reflections of the inserted material under the test with high attenuation of the relatively short waveguide. Waveguide, broadband transitions design, attenuators arrangements and the material under test attachment were designed using both the simulations and experiments.

Shielding Materials Waveguide Measurement about 400 MHz

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Knowledge of shielding materials attenuation is highly demanded for construction of shielded boxes or spaces and for other applications. In the paper the measurement of shielding materials attenuation up to 100 dB is presented. The main focus is given to a design of measurement unit and demonstration of measured data.

Site-Specific Space-Time Simulations of LMDS Performance Using Radar Rainfall Data

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    In this paper a concept of site-specific space-time simulations rain events are presented based on actual radar data. A database of radar data for numerous types of rain events has been established to enable system testing under different conditions. Various aspects of the system performance like site diversity can be evaluated by the simulation tool.

Space-Time Simulations of Point-to-multipoint Radio Systems Performance During Rain Events Using Radar Data

Synthesis of Dualband Broadside Radiated Microstrip Patch Antenna Operating with TM10 and TM21 Modes

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Novel concept for the synthesis of linearly polarized broadside radiated dualbad microstrip patch antenna has been used. Presented novel approach uses basic and suitable higher modes of patch resonator that are modified by appropriate patch surface perturbation so that outbalancing current component in the direction of demanded polarization is dominant at bot design frequencies. This concept is differenct than standard approach that use additional passive resonators in the same metal level as feeded patch or in other layers in so called stacked arrangement of another frequently used concept that modify patch by introducing suitably shaped perturbing elements such as slots and nothes. These snadard approaches has common feature namely that additional basic modes or basic resonances of parasitic parts are excited. Proposed novel approach has been verified on model of dualband 3.5/5.5 GHz microstrip patch antenna.

Synthesis of Planar Antennas with the use of Higher Order Modes Resonances

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The usage of higher order modes for realization of two planar antennas with dualband performance and higher directivity has been studied the help of IE3D planar simulator. 2.4/5 GHz linearly polarized dualband microstrip patch antenna that is designed by novel concept that uses basic TM10 and modified TM21 modes for achieving dualband performance with the demanded linear polarization in both frequency bands has been studied as a first example. 2.45 GHz three half-wavelength slot radiator has been simulated as a second example. Structures of both radiators have been modified in such a way so that broadside radiation has been achieved to be able to use them in an array.

Venkovní anténní měřicí pracoviště

  • Autoři: Černý, P., Bártík, H., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Sborník vzdělávacích a vědeckovýzkumných činností a nabídek. Praha: IEEE Czechoslovakia Section, 2004. pp. 6-8. ISBN 80-86582-15-9.
  • Rok: 2004
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Poster prezentuje úlohy, které vznikly jako projekt FRVŠ k podpoře výuky fázovaných anténních řad vyučovaných na katedře elektromagnetického pole. Tyto úlohy demonstrují vlivy amplitud a fázi napájecích proudů, rozmístění anténních elementů a vlivu jejichvlastních parametrů na celkový vyzařovací diagram řady a její parametry.

Výsledky projektu - LabLink - Virtual student exchange by linking laboratories

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Pro technicky orientované studenty je práce v laboratořích velmi důležitou součástí vzdělávání. Laboratorní výuka je však velmi nákladná. V mezinárodním projektu LabLink mohou být laboratorní úlohy sdíleny mezi univerzitami virtuálně pomocí internetu. Původní výsledky (metodologie včetně praktické implementace) projektu LabLink je prezentována v článku.

Zobecněný přístup k problematice měření v mikrovlnné technice

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    V příspěvku jsou zmíněny metody měření, kalibrace a experimentální výsledky v oblasti mikrovlnné techniky.

Analýza chyb při měření EMC

Daulband Quarter Wavelength Plannar Antenna for Signal Detection in GSM 900/DCS 1800 Bands

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Properties of dual band quarter wavelength planar antenna for signal detection in GSM900/DCS1800 band are presented. The antenna consist of two quarter wavelength planar antennas with air dielectric with one point feed. Reflection coefficient in uplink subbands (from mobile station MS to base station BS) of both bands at presented antennas versions is not as good as is required for transmitting antennas but in case of antennas for signal detectionpurposes is quite goog enough. Directional characteristics has been measured too.

Education in Antennas - Phased Antenna Arrays

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The paper describes the new tasks related to the subjects taught at the Department of the electromangeic field. These tasks demonstrate the influences of supply amplitudes, supply phases, antenna element placement and antenna element parameters.

Education in Antennas - Phased Antenna Arrays

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The paper describes the new tasks related to the subjects taught at the Department of the electromagnetic field. These tasks demonstrate the influences of supply amplitudes, supply phases, antenna element placement and antenna element parameters.

Education in Antennas - Phased Antenna Arrays

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The paper describes the new tasks related to the subjects taught at the Department of the electromagnetic field. These tasks demonstrate the influences of supply amplitudes, supply phases, antenna element placement and antenna element parameters.

Efficient Analysis of the Microstrip Patch Antenna with Fractal Boundary

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Microstrip patch antenna with fractal boundary defined by Koch curve is introduced. The antenna is designed to work at higher operating mode wich exhibit localization property of the electric field close tothe antenna's boundary. Such higher eigenmode results in higher directivity. Antenna is solved in terms of the cavity model using FEM and resultsare refined by full-wave simulator IE3D. Good agreement between measurement and simulation was achieved.

Fázované anténní řady

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Poster prezentuje úlohy, které vznikly jako projekt FRVŠ k podpoře výuky fázovaných anténních řad vyučovaných na katedře elektromagnetického pole. Tyto úlohy demonstrují vlivy amplitud a fázi napájecích proudů, rozmístění anténních elementů a vlivu jejich vlastních parametrů na celkový vyzařovací diagram řady a její parametry.

Internetová forma pilotního projektu LABLINK v úloze měření směrových vlastností antén

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Základní metodologie přípravy a provozu vzdálené výuky pomocí distančních laboratoří a virtuálních laboratoří.

LABLINK - Novel Way of Distant Education and Training Antenna Measurement Project Implementation

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Radioelektronika 2003 - Conference Proceedings. Brno: VUT v Brně, FEI, Ústav radioelektroniky, 2003. pp. 320-323. ISBN 80-214-2383-8.
  • Rok: 2003
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Internet remote active access to laboratory training is open for distant students. Lablink pilot project is oriented on the methodology. "Laboratory" described in the paper is the specific antenna project implementation into the general methodology frame.

Lablink Pilot Project - On - line Distant EMC Education Shielding Materials Effectiveness Measurement Laboratory Training and Measurement Results

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    For technically oriented students, laboratory training in well-equipped labs is an important part of the education. EMC laborat.training is very expensive. In internat.LABLINK project, lab experiments can be exchanged between universities in a virtual Internet way. Orig. results (methodology as well as practical implementation) of LABLINK project using "Shielding effectiveness measurement" in anechoic chamber at the CTU are presented. Except the education layer of the project, the results of new shielding material testing were presented.

Microstrip Patch Antenna with Fractal Boundary: Design, Simulation and Results

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Microstrip patch antenna with fractal boundary defined by Koch curve is introduced. The antenna is designed to work at higher mode which exhibit localization property of the electric field close to the antenna's boundary. Such higher eigenmode results in higher directivity. Antenna is solved in terms of the cavity model using FEM and results are refined using full-wave electromagnetic simulator IE3D. Good agreement between measurement and simulation was achieved.

Návrh a vývoj antén

Návrh metodiky měření útlumu elektromagneticky stíněných komor s rozměry do 2 metrů

Perspektivní anténní struktury

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: COMITE 2003 - Grantové fórum. Praha: IEEE Czechoslovakia Section, 2003. pp. 17-18. ISBN 80-86582-10-8.
  • Rok: 2003

Results of Propagation Measurement of XPD, Absorption and Multipath Fading on 59.3 km Path at 13 GHz

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    A joint long term propagation experiment of TESTCOM and the Czech Technical University Prague at the frequency 13143 MHz with H polarisation over 59.3 km path was focused on XPD, absorption due to hydrometeors, and multipath fading. The measured data over 5-year period of observation were statistically processed. The cumulative time distributions of both the received copolar signal and the XPD signal for all fading events, exclusively for multipath fading events, and for absorpiton events due to hydrometeors were obtained for the individual months, the whole year periods, the worst month over year periods, the average year, and the average worst month. The results obtained are discussed and compared with ITU-R models.

Signal Fluctuations Due to the Tree Attenuation in a Millimeter Waveband

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The radio network planning for a Local Multipoint Distribution Systems (LMDS) is often complicated by the fact that the line of sight (LOS) between the transmitter and the receiver is blocked by the vegetation of small depth (single tree). Time series tree attenuation measurement results in 38 GHz frequency band are presented in this paper. The wind speed effect on signal fluctuation was studied as well.

Time-Series Prediction of Attenuation Caused by Trees for Fixed Wireless Access Systems Operating in Millimeter Waveband

Tree Attenuation Measurement Experiment in Millimeter Waveband

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Results obtained the vegetation attenuation experiment performed on 38 GHz are presented in this paper. Signal fading due to wind speed loading the tree, signal characteristics and the mean field variation in the shadowed area of the tree was investigated.

Ultra Broadband Horn Antenna

  • Autoři: Hradecký, Z., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: COMITE 2003. Praha: IEEE Czechoslovakia Section, 2003. pp. 65-68. ISBN 80-86582-09-4.
  • Rok: 2003
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Complete solution of the double ridged horn antenna design with operating bandwidth from 200 MHz to 2200 MHz is presented in this paper. General design of the double ridged horn is described, expecially the design of the transition between coaxial line and double ridged waveguide. Calculated results as impedance matching, gain and radiation patternare presented and measured results will be presented in the conference.

Venkovní anténní měřicí pracoviště

  • Autoři: Černý, P., Bártík, H., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Sborník vzdělávacích a vědeckovýzkumných činností a nabídek katedry elektromagnetického pole FEL ČVUT. Praha: Československá sekce IEEE, 2003. pp. 14-16. ISBN 80-86582-13-2.
  • Rok: 2003
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Poster prezentuje úlohy, které vznikly jako projekt FRVŠ k podpoře výuky fázovaných anténních řad vyučovaných na katedře elektromagnetického pole. Tyto úlohy demonstrují vlivy amplitud a fázi napájecích proudů, rozmístění anténních elementů a vlivu jejichvlastních parametrů na celkový vyzařovací diagram řady a její parametry.

Výuka antén s využitím softwaru MATHCAD

Vývoj antény pro zónová měření

Vývoj vlnovodu pro měření útlumu stínicích materiálů

Wideband Measurement of Insertion Loss of Shielding Materials

  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    The aim of this paper is description of development of unique workplace capable of wideband measurement of insertion loss of shielding materials from frequencies about tens of MHz. Special attention is dedicated to construction of ferrite absorber wall and to chosen method of measurement of material insertion loss. Some of results of measurements are presented and discussed as well.

Anténní laboratoř s bezodrazovou komorou

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: WORKSHOP - Vzdělávací fórum - nabídka aktivit. Praha: ČVUT FEL, Katedra elektromagnetického pole, 2002. p. 39-40. ISBN 80-86582-07-8.
  • Rok: 2002

Conparison of Microwave Structures Modeling Using Frequency Domain and Time Domain Analysis

  • Autoři: Hradecký, Z., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Radioelektronika 2002. Bratislava: Slovak University of Technology, Faculty of Civil Engineering, 2002. pp. 370-373. ISBN 80-227-1700-2.
  • Rok: 2002

Dynamický model útlumu vegetace při šíření mm vln

LABLINK - Distant Laboratory Pilot Project

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Odborné semináře. Praha: ČVUT FEL, Katedra elektromagnetického pole, 2002. p. 23-27. ISBN 80-86582-08-6.
  • Rok: 2002

LABLINK Project in Antenna Laboratory

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: WORKSHOP - Vzdělávací fórum - nabídka aktivit. Praha: ČVUT FEL, Katedra elektromagnetického pole, 2002. p. 9-15. ISBN 80-86582-07-8.
  • Rok: 2002

Microstrip Patch Antennas with Fractal Boundary

Mikropáskové antény s fraktální hranicí

Model of Dynamic Effects Caused by Vegetation

Návrh a vývoj antén

Optimalizace statistického modelu zástavby pro město Praha

Prelimary Study of Vegetation Effects on Signal Propagation in Millimeter Waveband

Scattering Measurement Experiment on 38 GHz - First Results

Vegetation Effects Modeling for Terrestrial Broadband Radio Access Systems Operating in Millimeter Waveband

Vegetation Effects on Signal Propagation in Millimeter Waveband

Venkovní anténní měřicí pracoviště

  • Autoři: Černý, P., Bártík, H., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: WORKSHOP - Grantové fórum. Praha: ČVUT FEL, Katedra elektromagnetického pole, 2002. pp. 69-71. ISBN 80-86582-06-X.
  • Rok: 2002

Antenna Laboratory

Area Coverage Modeling for Systems Operating in Millimeter Wave Band

Behavior of the Sierpinski Monopole Iterations

Comparison of Antennas Modeling at Frequency Domain and Time Domain

  • Autoři: Hradecký, Z., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: 10th Aachen Symposium on Signal Theory - Proceedings. Berlin: VDE Verlag, 2001. pp. 409-413. ISBN 3-8007-2610-6.
  • Rok: 2001

Design of Broadband Antenna (Double Ridged Horn)

  • Autoři: Hradecký, Z., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: COMITE 2001. Praha: IEEE Czechoslovakia Section, 2001. pp. 211-214. ISBN 80-902417-9-4.
  • Rok: 2001

Design of Double Ridged Horn Antenna in Frequency 8-18 GHz

  • Autoři: Hradecký, Z., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Radioelektronika 2001 - Conference Proceedings. Brno: VUT v Brně, FEI, Ústav radioelektroniky, 2001. pp. 238-241. ISBN 80-214-1861-3.
  • Rok: 2001

Fractal Structures in Antenna Technology

Fractals in Antenna Technology - New Analysis Approach

Historie, současnost a budoucnost výuky na katedře elektromagnetického pole ČVUT FEL v Praze

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: COMITE 2001 - Industry, Research and Education Forum. Praha: Československá sekce IEEE, 2001. pp. 3-13. ISBN 80-86582-01-9.
  • Rok: 2001

Kritéria návrhu antén pro mobilní komunikace

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Biologické systémy a elektromagnetické pole. Praha: ČVUT FEL, Katedra elektromagnetického pole, 2001. pp. 28-31. ISBN 80-01-02389-3.
  • Rok: 2001

New Fast Approach to Wideband Propagation Prediction in Picocells

Performance and Reliability of Advanced Telecommunication Systems using Millimetre Wavelengths in the Czech Republic

  • Autoři: Kvičera, V., Fišer, O., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Radioelektronika 2001 - Conference Proceedings. Brno: VUT v Brně, FEI, Ústav radioelektroniky, 2001. pp. 270-273. ISBN 80-214-1861-3.
  • Rok: 2001

Sierpinski Monopole Fractal Antenna - Simulation and Results

Signal Propagation Aspects for Local Multipoint Distribution System (LMDS) Operating in Millimeter Wave Band

Signal Propagation for Point-to-Multipoint Systems in Millimeter Wave Band

Vědeckovýzkumná činnost - historie a současnost na katedře elektromagnetického pole ČVUT FEL v Praze

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: COMITE 2001 - Industry, Research and Education Forum. Praha: Československá sekce IEEE, 2001. pp. 14-17. ISBN 80-86582-01-9.
  • Rok: 2001

Anechoic and EMC Chambers - Modelling, Design, Testing

Bio-elektromagnetické efekty - informace z konference "MILENIUM - AP 2000"

Electromagnetic Field in Anechoic and EMC Chambers - Part 1 - Modelling

EMC (EMI) Standards in RF Frequency Bands

EMI Standards and Measurement above 30 MHz

Indoor Propagation Modelling in Multi-Storey Buildings in Prague

Measurement Methods in Antenna Laboratory at the Department of Electromagnetic Field

New Approach to Coordination Distance Calculation

  • Autoři: prof. Ing. Miloš Mazánek, CSc., Hajný, M.
  • Publikace: Millenium Conference on Antennas and Propagation - AP 2000. Noordwijk: European Space Agency, 2000. pp. 781-784. ISBN 92-9092-776-3.
  • Rok: 2000

Novel Approach to Indoor Semi-deterministic Propagation Prediction

Novel Approach to Indoor Semi-Deterministic Propagation Prediction

Šíření elektromagnetických vln a antény pro mobilní komunikace, elektromagnetická kompatibilita

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Radiokomunikace 2000. Praha: ČVUT FEL, Katedra radioelektroniky, 2000. p. 511-543. ISBN 80-01-02142-4.
  • Rok: 2000

The First Results of Propagation Measurement on 59.3 km Path at 13 GHz: Multipath Fading, Hydrometeor Attenuation, and XPD

  • Autoři: Kvičera, V., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: ECRR 2000 - Seventh European Conference on Fixed Radio Systems and Networks. Berlin: VDE Verlag, 2000. pp. 305-308. ISBN 3-8007-257.
  • Rok: 2000

Výzkum, moderní technologie a praxe

Anechoic and EMC Chamber Modelling

  • Autoři: prof. Ing. Miloš Mazánek, CSc., Klepal, M.
  • Publikace: 9th International Czech-Slovak Scientific Conference Radioelektronika 99. Brno: VUT v Brně, 1999. pp. 237-240. ISBN 80-214-1327-1.
  • Rok: 1999

Anechoic Chamber Testing Methods

  • Autoři: prof. Ing. Miloš Mazánek, CSc., Bártík, H.
  • Publikace: The 10th Conference on Microwave Techniques COMITE 1999. Prague: Czechoslovakia Section IEEE, 1999. pp. 63-66. ISBN 80-902417-3-5.
  • Rok: 1999

Antény - minulost, přítomnost a možné směry jejich vývoje

Antény v moderní technice

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: 1. seminář "Spolupráce vysokých a středních škol" (výchova technické inteligence v oblasti elektrotechniky). Prague: Czechoslovakia Section IEEE, 1999. pp. 1-7. ISBN 80-902417-5-1.
  • Rok: 1999

Computations of Specific Rain Attenuation for Different Drop Size Distribution Based on the MMP Numerical Method

EMI Measurement in EMC Test Fascilities

First Results of Antenna and EMC Chamber Testing

  • Autoři: Bártík, H., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: 9th International Czech-Slovak Scientific Conference Radioelektronika 99. Brno: VUT v Brně, 1999. pp. 241-244. ISBN 80-214-1327-1.
  • Rok: 1999

Ku-band Rain Scattering Parameters Calculated by MMP Method

  • Autoři: Hajný, M., prof. Ing. Miloš Mazánek, CSc., Fišer, O.
  • Publikace: First International Workshop on Radiowave Propagation Modelling for SatCom Services at Ku-Band and Above. Noordwijk: European Space Agency, 1999. pp. 180-186. ISSN 1022-6656.
  • Rok: 1999

Low Profile Antennas

Mikrovlnná měřicí techníka - část 3. - Součanost a perspektivy radiové komunikace

Modelling and Testing PMC Systems Inside Buildings

Parametric Study of Aperture Stacked Patch

Perspektivy mikrovlnné techniky

Prediction of Electromagnetic Wave Scattering for Co-ordinate Distance Calculation

  • Autoři: Hajný, M., prof. Ing. Miloš Mazánek, CSc., Valenta, J., Kvičera, V.
  • Publikace: First International Workshop on Radiowave Propagation Modelling for SatCom Services at Ku-Band and Above. Noordwijk: European Space Agency, 1999. pp. 200-206. ISSN 1022-6656.
  • Rok: 1999

Radiokomunikace a mikrovlny - Současnost a perspektivy radiové komunikace

Šíření radiových vln v atmosféře

Specifika měření EMC na různých stanovištích

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Biologické systémy a elektromagnetické pole. Praha: ČVUT FEL, Katedra elektromagnetického pole, 1999. pp. 18-19. ISBN 80-01-01997-7.
  • Rok: 1999

900 MHz Signal Attenuation Measurement for Mobile Wireless Communications in Urban AREA

Absorbers for EMC Laboratories at Frequencies Above 500 MHz

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Biological Systems and Electromagnetic Field. Praha: ČVUT FEL, Katedra elektromagnetického pole, 1998. pp. 31-33. ISBN 80-01-01821-0.
  • Rok: 1998

Aktivity katedry elektromagnetického pole v oblasti antén a mikrovlnné techniky

Anechoic and EMC Chambers - Invited Paper

Anechoic Chambers Testing

Design and Testing of Anechoic Chambers for Antenna Measurement

EMC Laboratories at Frequencies Above 500 MHz

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Biological Systems and Electromagnetic Field. Praha: ČVUT FEL, Katedra elektromagnetického pole, 1998. pp. 34-37. ISBN 80-01-01821-0.
  • Rok: 1998

Mobilní a personální radiokomunikace na katedře elektromagnetického pole

Šíření elektromagnetických vln a antény pro mobilní komunikace, EMC v oblasti nad 500 MHz

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Radiokomunikace '98. Praha: ČVUT FEL, Katedra radioelektroniky, 1998. pp. 1401-1428. ISBN 80-01-01780-X.
  • Rok: 1998

2.45 GHz Band Microstrip Array

Attenuation and Rain Scattering Based on MMP Method

  • Autoři: Hajný, M., Bažant, L., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: COMITE 1997. Pardubice: Univerzita Pardubice, 1997. pp. 123-126. ISBN 80-902417-0-0.
  • Rok: 1997

Cavity Backed Patch Antenna with Shorted Nonradiating Edges

Cavity-Backed Path Antennas

  • DOI: 10.1049/cp:19970223
  • Odkaz: https://doi.org/10.1049/cp:19970223
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Several configurations of cavity-backed patch antennas are described and compared. Theoretical studies were accompanied with both impedance matching and radiation pattern measurements. The main goal of the project is to achieve smaller dimensions with a sufficient frequency bandwidth of microstrip low profile antennas. Two construction approaches-broadband cavity backed, shorted nonradiating edge, and slot & notch cut microstrip antenna-were combined

CNProp 2.0 - CAD Software for Frequency Planning in Cellular Communication Systems

Combined Microstrip Antenna Arrangements

Near-Field Antenna Measurement System

  • Autoři: Bártík, H., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Workshop 97. Praha: České vysoké učení technické v Praze, 1997. pp. 979-980.
  • Rok: 1997

Patch Antennas with Reduced Dimensions

Planar Near-field Antenna Measurement

  • Autoři: Bártík, H., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: COMITE 1997. Pardubice: Univerzita Pardubice, 1997. pp. 105-107. ISBN 80-902417-0-0.
  • Rok: 1997

Planning Tool for Channel Alignment in Cellular Networks

Využití infračervené a mikrovlnné radiometrie v zemědělství

  • Autoři: Grygar, J., prof. Ing. Miloš Mazánek, CSc., Veselý, J.
  • Publikace: Pomezí Čech a Moravy. Svitavy: Státní okresní archiv Svitav, 1997, pp. 233-242.
  • Rok: 1997

Automatizovaný systém pro měření směrových charakteristik antén

Broadband and Millimetric Propagation Effects

  • Autoři: prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Broadband and Millimetric Propagation Effects, International symposium. Brussels: COST Office, 1996. pp. 14-17.
  • Rok: 1996

Experimental Demonstration of the Ray Tracing Method

Propagation Study for Microwave Radio Systems, XPD, Interferences, Absorptions

Software for Cellular Network Propagation Studies - SNProp

The 37 GHz Short Distance Experiment

  • Autoři: Bártík, H., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: Workshop 96. Praha: České vysoké učení technické v Praze, 1996. pp. 763-764.
  • Rok: 1996

The Material Dielectric Characteristic Measurement

The Propagation of Electromagnetic Waves for CMR and PCS

Distribuce signálu pro mobilní komunikace

MM Wave Propagation Experiment

Multiradiometrická diagnostika sazenic lesních dřevin

  • Autoři: prof. Ing. Miloš Mazánek, CSc., Řešátko, M., Turzík, Z., Gregorová, E., Rumler, C.
  • Publikace: Lesnictví - Forestry. 1995, 41(1), 511-516.
  • Rok: 1995

Návrh VF radioreléových tras do 100GMz

Propagation Prediction in Microcells for UMF Personal Communication Systems

The 37 GHz Short Distance Experiment

The Antenna Characteristics Measurement System

Elektrotechnika a životní prostředí

Flat Fade Effects and Millimetre Wave Considerations

  • Autoři: Bažant, L., Bártík, H., Janík, J., prof. Ing. Miloš Mazánek, CSc., Zlámal, P.
  • Publikace: CTU Seminar 94. Praha: České vysoké učení technické v Praze, 1994. pp. 201-202.
  • Rok: 1994

Frequency Selective Fade Effects

  • Autoři: Janík, J., prof. Ing. Miloš Mazánek, CSc.,
  • Publikace: CTU Seminar 94. Praha: České vysoké učení technické v Praze, 1994. pp. 199-200.
  • Rok: 1994

Měření frekvenčně plochých úniků

  • Autoři: prof. Ing. Miloš Mazánek, CSc., Janík, J., Zlámal, P., Bártík, H.
  • Publikace: Konference elektrotechnické fakulty TU Košice. Košice: TU Košice, 1994. pp. 33-57.
  • Rok: 1994

Měření úniků elektromagnetických vln na pozemních trasách

  • Autoři: prof. Ing. Miloš Mazánek, CSc., Janík, J., Zlámal, P., Bártík, H., Kvičera, V.
  • Publikace: Radioelectronics. Brno: VUT v Brně, 1994. pp. 303-306.
  • Rok: 1994

Modernization of PhD. Studies in Radioelectronics

Microwave and Ir Radiometry of the Vegetation Cover

  • Autoři: prof. Ing. Miloš Mazánek, CSc., Janík, J., Pečený, Z., Rumler, C.
  • Publikace: Workshop 93. Praha: České vysoké učení technické v Praze, 1993. pp. 43-44.
  • Rok: 1993

Microwave Sensing for Propagation of Electromagnetic Waves

Multiradiometrická měření vybraných charakteristik semen lesních dřevin

  • Autoři: prof. Ing. Miloš Mazánek, CSc., Rumler, C., Gragorová, E., Turzík, Z., Řešátko, M.
  • Publikace: Lesnictví - Forestry. 1993, 39(6), 217-221.
  • Rok: 1993

Selektivní úniky na radioreléových trasách

The Antenna Pattern Deconvolution in Remote Sensing

  • Autoři: prof. Ing. Miloš Mazánek, CSc., Janík, J., Český, T.
  • Publikace: Workshop 93. Praha: České vysoké učení technické v Praze, 1993. pp. 203-204.
  • Rok: 1993

Activities in ACE WP 2.3.-1 on Wideband and Multiband Radiators

  • Autoři: Bonnedal, M., Angelopoulos, E., Antonino, E., Balling, P., Chan, K., Erickson, R., Lager, I., prof. Ing. Miloš Mazánek, CSc., Sorgel, W., Ubeda, E., Yarovoy, A.
  • Publikace: neuvedeno.
  • Pracoviště: Katedra elektromagnetického pole
  • Anotace:
    Developments in wireless communications and sensing require increasing wider frequency bands and that multiple functions can be provided by single antenna systems. This paper presents an overview of the activities of ACE work package 2.3-1, intended to gather and integrate expertise on a European level. We review here the progress of the partners and relate the work to other ACE activities.

Za stránku zodpovídá: Ing. Mgr. Radovan Suk