• Digitally-Compensated Wideband 60 GHz Test-Bed for Power Amplifier Predistortion Experiments 

  Pospíšil, Martin; Maršálek, Roman; Götthans, Tomáš; Urbanec, Tomáš (MDPI, 2021-02-20)

  Millimeter waves will play an important role in communication systems in the near future. On the one hand, the bandwidths available at millimeter-wave frequencies allow for elevated data rates, but on the other hand, the ...

• On the performance of electronically tunable fractional-order oscillator using grounded resonator concept 

  Šotner, Roman; Jeřábek, Jan; Polák, Ladislav; Langhammer, Lukáš; Stolařová, Hana; Petržela, Jiří; Andriukaitis, Darius; Valinevicius, Algimantas (Elsevier, 2021-02-20)

  Recent works target the design of fractional-order oscillators. However, some features of such circuits are not frequently considered in the design despite their importance in practice. This work provides an analysis of ...

• Implementation of the equivalent temperature measurement system as a part of the vehicle Heating, ventilation and Air-conditioning unit 

  Fišer, Jan; Povalač, Aleš; Urbanec, Tomáš; Pokorný, Jan; Fojtlín, Miloš (BioMed Central, 2015-06-29)

  Thermal comfort evaluation based on the Comfort zone diagram is relatively new and promising method [1] developed by Hkan O. Nilsson [2]. The method was developed mainly for non uniform indoor environments [3] such as ...

• Optimized Design of OTA-Based Gyrator Realizing Fractional-Order Inductance Simulator: A Comprehensive Analysis 

  Kubánek, David; Koton, Jaroslav; Dvořák, Jan; Herencsár, Norbert; Šotner, Roman (MDPI, 2021-01-01)

  A detailed analysis of an operational transconductance amplifier based gyrator implementing a fractional-order inductance simulator is presented. The influence of active element non-ideal properties on the gyrator operation ...

• Tunable Fractional-Order Capacitance Multiplier Using Current Gain Adjustment 

  Šotner, Roman; Jeřábek, Jan; Langhammer, Lukáš (IEEE, 2020-11-25)

  This paper brings new solution of linearly adjustable fractional-order capacitance multiplier. The adjustable current gain, linear in wide range of input current and with linear dependence on driving voltage, serves for ...

• Practical Design of Fractional-Order Resonator for Application in the Multiphase Oscillator 

  Šotner, Roman; Jeřábek, Jan; Langhammer, Lukáš; Kartci, Aslihan; Herencsár, Norbert; Metin, Bilgin (IEEE, 2020-11-25)

  This contribution introduces a new simple electronically adjustable resonator for implementation in design of the fractional-order multiphase oscillator created with parallel connection of this resonator and negative ...

• New Chaotic Oscillator Derived from Class C Single Transistor-Based Amplifier 

  Petržela, Jiří (Hindawi, 2020-11-06)

  This paper describes new autonomous deterministic chaotic dynamical system having single unstable saddle-spiral fixed point. Mathematical model originates in the fundamental structure of class C amplifier. Evolution of ...

• Voltage Differencing Current Conveyor Differential Input Transconductance Amplifier: Novel Active Element and Its Resistorless Filtering Application 

  Šotner, Roman; Jeřábek, Jan; Langhammer, Lukáš; Petržela, Jiří; Jaikla, Winai; Tuntrakool, Sunti (IEEE, 2019-10-30)

  This paper introduces novel modification of active element based on current conveyor transconductance amplifier core abbreviated as current controlled voltage differencing current conveyor differential input transconductance ...

• Electronically Tunable Oscillator Utilizing Reinforced Controllable Parameters 

  Langhammer, Lukáš; Šotner, Roman; Domanský, Ondřej (IEEE, 2019-10-31)

  This paper presents a novel solution of an oscillator with electronically adjustable oscillation condition (CO) and frequency of oscillations (FO). Oscillation condition is controlled by current gain and frequency of ...

• Binary Memory Implemented by Using Variable Gain Amplifiers With Multipliers 

  Petržela, Jiří; Šotner, Roman (IEEE, 2020-11-01)

  This work describes design process toward fully analogue binary memory where two coupled piecewise-linear (PWL) resistors are implemented using novel network topology with voltage gain amplifiers (VGA). These versatile ...

• Reconnection-less Reconfigurable Low-Pass Filtering Topology Suitable for Higher-Order Fractional-Order Design 

  Langhammer, Lukáš; Dvořák, Jan; Šotner, Roman; Jeřábek, Jan; Bertsias, Panagiotis (Elsevier, 2020-09-01)

  The paper discusses a new design of a current–mode reconnection–less reconfigurable fractional–order (FO) low–pass filter of various orders. The filtering structure is based on a 4th–order leap–frog topology using operational ...

• Capacitance Multiplier Using Small Values of Multiplication Factors for Adjustability Extension and Parasitic Resistance Cancellation Technique 

  Šotner, Roman; Jeřábek, Jan; Polák, Ladislav; Petržela, Jiří (IEEE, 2020-08-05)

  This paper presents a new concept of a capacitance multiplier using the topology of differential voltage buffer and current conveyor, where the capacitor is connected to the current input terminal. The presented topology ...

• Comparison of Simple Design Methods for Voltage Controllable Resistance 

  Šotner, Roman; Domanský, Ondřej; Langhammer, Lukáš; Petržela, Jiří (IEEE, 2020-04-16)

  This paper compares several ways of electronic resistance control for tunable applications (filters, oscillators, amplifiers, etc.). Simulation (PSpice) and experimental tests of basic J-FET transistor-based adjustable ...

• Fracmemristor chaotic oscillator with multistable and antimonotonicity properties 

  Lu, Haikong; Petržela, Jiří; Götthans, Tomáš; Rajagopal, Karthikeyan; Sajad, Jafari; Hussain, Iqtadar (Elsevier, 2020-06-17)

  Memristor is a non-linear circuit element in which voltage-current relationship is determined by the previous values of the voltage and current, generally the history of the circuit. The nonlinearity in this component can ...

• The CMOS Highly Linear Current Amplifier with Current Controlled Gain for Sensor Measurement Applications 

  Prokop, Roman; Šotner, Roman; Kledrowetz, Vilém (MDPI, 2020-08-18)

  This paper introduces a new current-controlled current-amplifier suitable for precise measurement applications. This amplifier was developed with strong emphasis on linearity leading to low total harmonic distortion (THD) ...

• New Low-Voltage CMOS Differential Difference Amplifier (DDA) and an Application Example 

  Šotner, Roman; Herencsár, Norbert; Kledrowetz, Vilém; Kartci, Aslihan; Jeřábek, Jan (IEEE, 2018-08-05)

  The paper presents a newly designed structure of a low-voltage differential difference amplifier (DDA). The novel implementation brings significant reduction of complexity in comparison to readily available operational ...

• Frequency Corrector Using Voltage Differencing Current Conveyor Transconductance Amplifiers 

  Šotner, Roman; Petržela, Jiří; Jeřábek, Jan; Langhammer, Lukáš (IEEE, 2019-11-29)

  This paper brings new type of electronically adjustable bilinear two port (allowing zero, pole and gain adjustment) applied in simple two-band frequency corrector. The bilinear two port employs single current controlled ...

• CMOS-RC Colpitts Oscillator Design Using Floating Fractional-Order Inductance Simulator 

  Kartci, Aslihan; Herencsár, Norbert; Brančík, Lubomír; Salama, Khaled Nabil (IEEE, 2018-08-05)

  This paper deals with CMOS fractional-order inductance (FoL) simulator design and its utilization in 2.75th-order Colpitts oscillator providing high frequency of oscillation. The proposed floating FoL is composed of two ...

• Conversion of a MISO Filter into its Reconnectionless Reconfigurable Form with Complex Active elements 

  Langhammer, Lukáš; Šotner, Roman (IEEE, 2020-04-23)

  This paper aims to show an easy way how to design a reconnection-less reconfigurable filter based on the modification of an existing MISO filter. The proposed filter offers the same transfer functions as the structure ...

• Psychological Stress Detection in Speech Using Return-to-opening Phase Ratios in Glottis 

  Staněk, Miroslav; Sigmund, Milan (Kaunas University of Technology, 2015-10-12)

  This paper is focused on investigation of psychological stress in speech signal using shapes of normalised glottal pulses. The pulses were estimated by two algorithms: the Direct Inverse Filtering and Iterative and Adaptive ...

View more