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Tunable Universal Fully-Differential Filter With
Operational Transresistance Amplifier
Polesakova, Zuzana
anglický
The new single-ended (S-E) second order frequency filter providing transfer function of Low Pass (LP), High Pass (HP), Band Pass (BP), Band Stop (BS) and All Pass (AP) is presented in this paper. The cut-off frequency is tunable up to 3 MHz. Also the fully-differential (F-D) version of the filter is presented and so is the transformation method which is in this case the Signal Flow Graph (SFG). The design filter can be implemented with discretive active devices or as an Integrated Circuit (IC). The features of both S-E and F-D filters are verified using PSpice simulations comparing ideal and behavioral models of the active devices.
Klíčová slova:
Fully-Differential Frequency Filter; Signal Flow Graph; Universal Filter; OTRA
Plné texty jsou dostupné v digitálním repozitáři NUŠL
Tunable Universal Fully-Differential Filter With
Operational Transresistance Amplifier
The new single-ended (S-E) second order frequency filter providing transfer function of Low Pass (LP), High Pass (HP), Band Pass (BP), Band Stop (BS) and All Pass (AP) is presented in this paper. The ...
Reconfigurabe Waveguide Divider
Cupal, Miroslav
anglický
The design and implementation of the textile integrated waveguide (TIW) switch for ISM band is presented. The traveling electromagnetic wave is controlled by conductive posts with a circular slot. PIN diodes are used for switching electromagnetic wave to two directions. The simulations results are presented as parametric analysis.
Klíčová slova:
TIW; textile integrated waveguide; divider; reconfigurable; textile
Plné texty jsou dostupné v digitálním repozitáři NUŠL
Reconfigurabe Waveguide Divider
The design and implementation of the textile integrated waveguide (TIW) switch for ISM band is presented. The traveling electromagnetic wave is controlled by conductive posts with a circular slot. PIN ...
Influence Of Interferences Caused By Non-Linear
Power Amplifier In Multi-User Generalized
Frequency Division Multiplex Scenario
Harvanek, Michal
anglický
This article is aimed to the problematic of interferences in multi-user scenarios which can occur in modern mobile communication networks. Hence of new modulation schemes as a Filter Bank Multi Carrier (FBMC), Generalized Frequency Division Multiplex (GFDM) or another modulation scheme with low out of band emission there can occur problems with interferences especially when user equipments are using non-linear power amplifiers. The non-linear system causes radiation into adjacent channel which can lead to interferences with another user transmitting in this channel. This paper explains impact of such interferences to Error Vector Magnitude (EVM) of demodulated signal for different frequency spacing between users and also describe influence of interferences for different signal noise ratio. To remove inter-carrier interferences, the self interference cancellation method is used.
Klíčová slova:
Power amplifier; amplifier modeling; distortion; interferences; FBMC; GFDM; 5G
Plné texty jsou dostupné v digitálním repozitáři NUŠL
Influence Of Interferences Caused By Non-Linear
Power Amplifier In Multi-User Generalized
Frequency Division Multiplex Scenario
This article is aimed to the problematic of interferences in multi-user scenarios which can occur in modern mobile communication networks. Hence of new modulation schemes as a Filter Bank Multi ...
Direct Learning Architecture For Digital
Predistortion With Real-Valued Feedback
Král, Tomáš Král, Jan
anglický
The power efficiency is a key parameter of modern comunication systems. Efficient nonlinear power amplifiers are linearised using digital predistorters. Conventional predistorters require two ADCs in the feedback. In this paper we have proposed a modification of the direct learning architecture using solely one ADC in the feedback and an RF mixer instead of a quadrature mixer. This allows us to minimise the system complexity and power consumtion and maximise the efficiency. The proposed architecture has been verified experimentally and compared to the conventional digital predistorters. We have shown that it can achieve same linearisation performance as the conventional architecture with two ADCs. Moreover the proposed method outperformed the conventional DPD with indirect learning architecture.
Klíčová slova:
digital predistortion; direct learning architecture; real-valued feedback
Plné texty jsou dostupné v digitálním repozitáři NUŠL
Direct Learning Architecture For Digital
Predistortion With Real-Valued Feedback
The power efficiency is a key parameter of modern comunication systems. Efficient nonlinear power amplifiers are linearised using digital predistorters. Conventional predistorters require two ADCs in ...
Comparison Of Different Approaches To
Adaptation Of Unscented Kalman Filter
For Non-Odometry Slam
Klečka, Jan
anglický
This paper is aimed at utilizing of an Unscented Kalman filter (UKF) for application on non-odometry SLAM problem. Non-odometry SLAM problem lacks state transitions function for part of state vector so theoretical part of the paper describes the derivation of three proposed modifications. The experimental part then shows experiments which evaluate modifications performance in reference to Extended Kalman filter. Experiments are based on simulation of monocular photogrammetry reconstruction problem.
Klíčová slova:
Unscented Kalman filter; UKF; SLAM; Recurrent estimation
Plné texty jsou dostupné v digitálním repozitáři NUŠL
Comparison Of Different Approaches To
Adaptation Of Unscented Kalman Filter
For Non-Odometry Slam
This paper is aimed at utilizing of an Unscented Kalman filter (UKF) for application on non-odometry SLAM problem. Non-odometry SLAM problem lacks state transitions function for part of state vector ...
Virtual Batch Manufacturing
Benešl, Tomáš
anglický
This paper describes a possible way to create digital twin of a batch production process. This virtual model of the batch system can be used for testing ISA-88 and ISA-95 with a virtual or real PLC without real system. There is also a possible use for education in labs with PLCs to show a behavior of a batch actors (valve, mixer, heater etc.) and ways to control, which can be tested in the virtual manufacturing system.
Klíčová slova:
ISA-95; ISA-88; Siemens; PLC; Step7; C#; Virtual manufacturing; Industry 4.0
Plné texty jsou dostupné v digitálním repozitáři NUŠL
Virtual Batch Manufacturing
This paper describes a possible way to create digital twin of a batch production process. This virtual model of the batch system can be used for testing ISA-88 and ISA-95 with a virtual or real PLC ...
Semi-Global Solutions To Mixed-Type Functional
Differential Equations
Vážanová, Gabriela
anglický
The purpose of this paper is to give sufficient conditions for existence of right semi-global solutions to mixed-type functional differential equations. We also give an example to illustrate applicability of the result.
Klíčová slova:
semi-global solutions; mixed-type functional differential equations; delayed argument; advanced argument; monotone iterative method
Plné texty jsou dostupné v digitálním repozitáři NUŠL
Semi-Global Solutions To Mixed-Type Functional
Differential Equations
The purpose of this paper is to give sufficient conditions for existence of right semi-global solutions to mixed-type functional differential equations. We also give an example to illustrate ...
Hybrid Microphone Preamplifier With Variable
Selection Of Amplifier Technology
Musil, Tomáš
anglický
This paper deals with the design of a studio level hybrid microphone pre-amplifier using a vacuum tube and semiconductor technology. The pre-amplifier circuit also contains an analog VU meter, 48 V phantom power supply, variable high pass filter, phase inverter switch and adjustable stage input impedance. This paper also deals with the design of a multi-voltage power supply unit and microprocessor controller unit ensuring completely automatic amplifier functions. The end of the paper is dedicated to a characteristics measurement determining its parameters.
Klíčová slova:
Vacuum tube; phantom power; microphone; microprocessor; operational amplifier; preamplifier; triode; heating
Plné texty jsou dostupné v digitálním repozitáři NUŠL
Hybrid Microphone Preamplifier With Variable
Selection Of Amplifier Technology
This paper deals with the design of a studio level hybrid microphone pre-amplifier using a vacuum tube and semiconductor technology. The pre-amplifier circuit also contains an analog VU meter, 48 V ...
Optical Fibers Forming For Optical Sensors
Research
Jelínek, Michal
anglický
We present development of new methods and techniques of the splicing and shaping optical fibers with focusing to development new sensors. We developed new techniques of splicing for standard Single Mode (SM) and Multimode (MM) optical fibers and optical fibers with different diameters in the wavelength range from 532 to 1550 nm. Together with development these techniques we prepared other techniques to splicing and shaping special optical fibers like as Polarization-Maintaining (PM) or hollow core Photonic Crystal Fiber (PCF) and theirs cross splicing methods with focus to minimize backreflection and attenuation. Splicing special optical fibers, especially PCF fibers with standard telecommunication and other SM fibers, can be done by light adjustment of our developed techniques.
Klíčová slova:
microstructured fibers; optical sensors; shaping optical fibers; splicing optical fibers; tapering optical fibers
Plné texty jsou dostupné v digitálním repozitáři NUŠL
Optical Fibers Forming For Optical Sensors
Research
We present development of new methods and techniques of the splicing and shaping optical fibers with focusing to development new sensors. We developed new techniques of splicing for standard Single ...
Application Of Optimization Algorithms To
The Genome Assembly
Jugas, Robin
anglický
The paper results from development of new sequencing methods together with the need of suitable genome assembly algorithms. It combines the genomic signal processing, correlation techniques and optimization algorithms for solving assembly task. Genomic signals are made by conversion of letter-based DNA into the form of digital signal, thus the methods of digital signal processing can be applied. Possible overlaps between reads converted into signals are found by computing correlation coefficient similarly to cross-correlation. We acquire similarity matrix and the task is to find the path through it achieving minimum distance criterion. For the task, the two optimization techniques were employed: ant colony optimization (ACO) and simulated annealing (SA). The result implies the possibility of using the ACO at the task of creating path through similarly to graphtheory-based algorithms.
Klíčová slova:
bioinformatics; genome assembly; genomic signal processing; optimization tec
Plné texty jsou dostupné v digitálním repozitáři NUŠL
Application Of Optimization Algorithms To
The Genome Assembly
The paper results from development of new sequencing methods together with the need of suitable genome assembly algorithms. It combines the genomic signal processing, correlation techniques and ...
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