Search Results - "Hoffmann, Karel"

Precise Measurement Using Coaxial-to-Microstrip Transition Through Radiation Suppression by Moravek, Ondrej, Hoffmann, Karel, Polivka, Milan, Jelinek, Lukas

“…This paper presents a study about the radiation problem of coaxial-to-microstrip launchers and suggests their improvement with a novel design. The proposed…”
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Novel Waveguide Sensors for Contactless Ultrashort-Distance Measurements by Baskakova, Aleksandra, Hoffmann, Karel

“…Novel sensors for ultrashort-distance measurements, with choke flanges applied at the open ends of both a WR10 waveguide and a circular waveguide, featuring a…”
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Uncertainties Caused by Noise for Microwave Interferometric and Reflection Measurements of Extreme Reflection Coefficients by Haase, Martin, Hoffmann, Karel

“…This article concerns an uncertainty analysis of interferometric transmission measurements and standard reflection measurements of extreme impedances (extreme…”
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W-Band Imaging Sensor Using a Rectangular Waveguide Structure With Choke by Baskakova, Aleksandra, Hoffmann, Karel

“…A new application of a rectangular waveguide structure with a choke from Baskakova and Hoffmann (2021) is proposed for high-contrast imaging in the W-band. As…”
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Design of Microstrip Dual-Mode Impedance Transformers by Baskakova, Aleksandra, Hoffmann, Karel

“…new four-port component, dual-mode impedance transformer for wideband matching of two microstrip lines with equal characteristic impedance and a coupled…”
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Scalar Method for Reading of Chipless RFID Tags Based on Limited Ground Plane Backed Dipole Resonator Array by Kracek, Jan, Svanda, Milan, Hoffmann, Karel

“…In this paper, we propose a novel frequency-domain reading method for the chipless radio frequency identification (RFID) tags. It is based on a single scalar…”
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Evaluation of Insertion Losses of Power EMC Filters Operated in Actual Impedance Environment by Hudec, Premysl, Skvor, Zbynek, Hoffmann, Karel

“…Insertion losses (ILs) of power electromagnetic compatibility (EMC) filters are measured often up to the relatively high GHz region, usually by standard…”
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Six-Port Spatial Electromagnetic Wave Measurement by Adler, Viktor, Hoffmann, Karel

“…A new method for measuring free-space electromagnetic waves, based on a scalar interferometric measurement principle similar to the six-port concept, is…”
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Advanced Evaluation of Minimum Insertion Loss of Power-Line EMI/RFI Filters in RF and Microwave Frequency Bands by Haase, Martin, Hoffmann, Karel, Hudec, Premysl

“…This paper concerns a new approach for the characterization of power-line electromagnetic interference/radio-frequency interference (EMI/RFI) filters in a…”
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General Method for Characterization of Power-Line EMI/RFI Filters Based on S-Parameter Evaluation by Haase, Martin, Hoffmann, Karel, Hudec, Premysl

“…This paper deals with a general working approach for determining the lowest possible insertion loss of power-line interference filters in their stop bands at…”
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Authors' Reply by Hoffmann, Karel, Skvor, Zbynek

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Authors' reply by Hoffmann, Karel, Skvor, Zbynek

“…In order to obtain results in the above paper, we used five parameters. According to our statement that inserting a transmission line between the scalar…”
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Authors' reply by Hoffmann, Karel, Skvor, Zbynek

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A Method for Direct Impedance Measurement in Microwave and Millimeter-Wave Bands by Randus, M., Hoffmann, K.

“…A novel method for direct impedance measurement using a common vector network analyzer (VNA) is introduced and experimentally verified. In commonly used…”
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Novel Multimode Planar Absorbing Structure by Prihoda, M., Hoffmann, K.

“…A block of absorbing material covered by a conductive plate and placed on a microstrip line forms a structure which makes possible multimode propagation. The…”
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Microwave Impedance Measurement for Nanoelectronics by M. Randus, K. Hoffmann

“…The rapid progress in nanoelectronics showed an urgent need for microwave measurement of impedances extremely different from the 50Ω reference impedance of…”
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Measurement and Simulation of Coaxial to Microstrip Transitions' Radiation Properties and Substrate Influence by O. Moravek, K. Hoffmann

“…A radiation and electro-magnetic (EM) field analysis of coaxial-to-microstrip transitions is presented. Radiation is quantified by simulation and measurement…”
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Investigation of Waveguide Sensors for Ultra-Short-Distance Measurements by Baskakova, Aleksandra, Hoffmann, Karel

“…Experimental study of two R100 open waveguides with a plain and a choke flanges at the ends newly applied as sensors for ultra-short distance measurements is…”
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Design of a Scalar Free-Space Measurement System by Adler, Viktor, Hoffmann, Karel

“…This article offers insight into the design and realization of a scalar free-space measurement system applicable to inverse synthetic aperture imaging…”
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Improvement to Load-pull Technique for Design of Large-signal Amplifier in K band by O. Moravek, K. Hoffmann

“…An improvement to the load-pull technique for a large-signal design of a transistor amplifier is proposed. On the contrary to the current load-pull technique –…”
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