He received the Ph.D. degree in Electrical Engineering in 1976, and the Prof. degree in 1997, both from the Technical University of Brno. From 1990 untill 2014 he has been Head of the Dept. of Telecommunications, Faculty of Electrical Engineering and Computer Science, Brno University of Technology, Brno, Czech Republic. His research work is concentrated on problems concerned with accuracy of analog circuits and mutual conversion of analog and digital signals. In cooperation with AMI Semiconductor Czech, Ltd. (now ON Semiconductor Czech Republic, Ltd.) he has developed number of novel active function blocks for analog signal processing such as universal current conveyor (UCC), universal voltage conveyor (UVC), programmable current amplifier (PCA), and others. He is an author or co-author of more than 650 research articles published in international journals or conference proceedings. Professor Vrba is a Member of IEEE, IEICE, and Associate Member of IET.
List of 5 most important projects from the past 3 years
• 2012 – 2015 Hybrid telephone exchange with direct connection to optical network. Czech Ministry of Industry and Trade, reg. number: FR-TI4/580.
• 2012 – 2014 Integration server with cryptographic protection. Czech Ministry of Industry and Trade, reg. number: FR-TI4/647.
• 2012 – 2014 System for cryptographic protection of electronic identity. Technology Agency of the Czech Republic, reg. number: TA02011260.
• 2012 – 2014 System for cryptographic protection of electronic identity. Technology Agency of the Czech Republic, reg. number: TA02011260
• 2011 -2013 Multifunction programmable infusion pump for patient-controlled analgesia with telemonitoring option and attachment to hospital information systems. Czech Ministry of Industry and Trade, reg. number: FR-TI3/234.
List of 5 most important results from the past 3 years
• JEŘÁBEK, J.; VRBA, K.; KOTON, J.; HERENCSÁR, N.; KOUDAR, I. Prototype of Low Noise Variable Gain Amplifier (LNVGA), 2012.
• SCHIMMEL, J.; VRBA, K.; KOTON, J.; HANÁK, P. Modular system for processing audio signals – functional sample, 2012.
• MÍČA, I.; PŘINOSIL, J.; ATASSI, H.; VRBA, K.; SMÉKAL, Z. Software for detecting of voice activity, 2011.
• ATASSI, H.; PŘINOSIL, J.; MÍČA, I.; VRBA, K.; SMÉKAL, Z. Software for the evaluation of the emotional speaker state for language Czech, Slovak, Polish, Russian, Italian and French, 2011.
• JEŘÁBEK, J.; VRBA, K.; KOUDAR, I.: Wide Band width Controllable Quad Current Operational Amplifier (COAK) – functional sample, 2010.
Publications
Journal papersConference papers
ŠOTNER, R.; JEŘÁBEK, J.; HERENCSÁR, N.; DOSTÁL, T.; VRBA, K. Design of Z-copy controlled- gain voltage differencing current conveyor based adjustable functional generator. Microelectronic Journal, 2015, vol. 46, no. 2, p. 143-152. ISSN: 0026- 2692.
KOTON, J.; VRBA, K.; HERENCSÁR, N. Voltage-mode full- wave rectifier based on DXCCII. ANALOG INTEGRATED CIRCUITS AND SIGNAL PROCESSING, 2014, vol. 2014, no. 1, p. 1-9. ISSN: 0925- 1030.
JEŘÁBEK, J.; ŠOTNER, R.; VRBA, K. Electronically Adjustable Triple-Input Single- Output Filter with Voltage Differencing Transconductance Amplifier. Revue Roumaine des Sciences Techniques - Serie Électrotechnique et Énergétique, 2014, vol. 59, no. 2, p. 163-172. ISSN: 0035- 4066.
ŠOTNER, R.; JEŘÁBEK, J.; HERENCSÁR, N.; PETRŽELA, J.; VRBA, K.; KINCL, Z. Linearly Tunable Quadrature Oscillator Derived from LC Colpitts Structure Using Voltage Differencing Transconductance Amplifier and Adjustable Current Amplifier. ANALOG INTEGRATED CIRCUITS AND SIGNAL PROCESSING, 2014, vol. 81, no. 1, p. 121-136. ISSN: 0925- 1030.
KOTON, J.; HERENCSÁR, N.; VRBA, K.; METIN, B. Voltage- mode multifunction filter with mutually independent Q and w0 control feature using VDDDAs. ANALOG INTEGRATED CIRCUITS AND SIGNAL PROCESSING, 2014, vol. 2014, no. 1, p. 1-8. ISSN: 0925- 1030.
KOTON, J.; HERENCSÁR, N.; VRBA, K. Analysis of Dynamic Performance of Half- Wave Rectifiers and its Improvements. Elektronika Ir Elektrotechnika, 2014, vol. 20, no. 2, p. 40-43. ISSN: 1392- 1215.
KUBÁNEK, D.; KHATEB, F.; VRBA, K. Square Wave Generator with Voltage- Controlled Frequency Based on Universal Current Conveyor. Przeglad Elektrotechniczny, 2013, vol. 2013, no. 2a, IF: 0. 244, p. 191-194. ISSN: 0033- 2097.
HERENCSÁR, N.; KOTON, J.; VRBA, K. A Modified CFTA (MCFTA) and Its Application to SITO-Type Current-Mode Universal Active- C Filter. Journal of Active and Passive Electronic Devices, 2013, vol. 7, no. 4, p. 1-9. ISSN: 1555- 0281.
HERENCSÁR, N.; MINAEI, S.; KOTON, J.; YUCE, E.; VRBA, K. New Resistorless and Electronically Tunable Realization of Dual-Output VM All- Pass Filter Using VDIBA. ANALOG INTEGRATED CIRCUITS AND SIGNAL PROCESSING, 2013, vol. 74, no. 1, p. 141-154. ISSN: 0925- 1030.
JEŘÁBEK, J.; KOTON, J.; ŠOTNER, R.; VRBA, K. Adjustable band-pass filter with current active elements: two fully-differential and single- ended solutions. ANALOG INTEGRATED CIRCUITS AND SIGNAL PROCESSING, 2013, vol. 74, no. 1, p. 129-139. ISSN: 0925- 1030.
HERENCSÁR, N.; CICEKOGLU, O.; ŠOTNER, R.; KOTON, J.; VRBA, K. New resistorless tunable voltage- mode universal filter using single VDIBA. ANALOG INTEGRATED CIRCUITS AND SIGNAL PROCESSING, 2013, vol. 76, no. 2, p. 251-260. ISSN: 0925- 1030.
ŠOTNER, R.; HRUBOŠ, Z.; HERENCSÁR, N.; JEŘÁBEK, J.; DOSTÁL, T.; VRBA, K. Precise Electronically Adjustable Oscillator Suitable for Quadrature Signal Generation Employing Active Elements with Current and Voltage Gain Control. CIRCUITS SYSTEMS AND SIGNAL PROCESSING, 2013, vol. 2013, no. online first, p. 1-35. ISSN: 0278- 081X.
JANEČEK, M.; KUBÁNEK, D.; VRBA, K. Voltage-Controlled Square/ Triangular Wave Generator with Current Conveyors and Switching Diodes. International Journal of Advances in Telecommunications, Electrotechnics, Signals and Systems, 2012, vol. 1, no. 2- 3, p. 1-4. ISSN: 1805- 5443.
HERENCSÁR, N.; KOTON, J.; LAHIRI, A.; METIN, B.; VRBA, K. A Voltage Gain-Controlled Modified CFOA And Its Application in Electronically Tunable Four-Mode All- Pass Filter Design. International Journal of Advances in Telecommunications, Electrotechnics, Signals and Systems, 2012, vol. 1, no. 1, p. 20-25. ISSN: 1805- 5443.
ŠOTNER, R.; LAHIRI, A.; JEŘÁBEK, J.; HERENCSÁR, N.; KOTON, J.; DOSTÁL, T.; VRBA, K. Special Type of Three- Phase Oscillator Using Current Gain Control for Amplitude Stabilization. International Journal of Physical Sciences, 2012, vol. 7, no. 25, p. 3089-3098. ISSN: 1992- 1950.
METIN, B.; HERENCSÁR, N.; VRBA, K. A CMOS DCCII with a Grounded Capacitor Based Cascadable All- Pass Filter Application. Radioengineering, 2012, vol. 21, no. 2, p. 718-724. ISSN: 1210- 2512.
HERENCSÁR, N.; LAHIRI, A.; VRBA, K.; KOTON, J. An electronically tunable current- mode quadrature oscillator using PCAs. INTERNATIONAL JOURNAL OF ELECTRONICS, 2012, vol. 99, no. 5, p. 609-621. ISSN: 0020- 7217.
HERENCSÁR, N.; LAHIRI, A.; KOTON, J.; VRBA, K.; METIN, B. Realization of Resistorless Lossless Positive and Negative Grounded Inductor Simulators Using Single ZC- CCCITA. Radioengineering, 2012, vol. 21, no. 1, p. 264-272. ISSN: 1210- 2512.
ŠOTNER, R.; JEŘÁBEK, J.; HERENCSÁR, N.; HRUBOŠ, Z.; DOSTÁL, T.; VRBA, K. Study of Adjustable Gains for Control of Oscillation Frequency and Oscillation Condition in 3R- 2C Oscillator. Radioengineering, 2012, vol. 21, no. 1, p. 392-402. ISSN: 1210- 2512.
HERENCSÁR, N.; VRBA, K.; KOTON, J. A Novel Current-Mode KHN- Equivalent Biquad Using Three CFTAs. Journal of Active and Passive Electronic Devices, 2012, vol. 7, no. 3, p. 201-208. ISSN: 1555- 0281.
HERENCSÁR, N.; KOTON, J.; VRBA, K.; LATTENBERG, I. Voltage-Controlled Current- Mode Multifunction Filter Employing CFTAs and PCAs. Journal of Active and Passive Electronic Devices, 2012, vol. 7, no. 1- 2, p. 61-69. ISSN: 1555- 0281.
HERENCSÁR, N.; KOTON, J.; VRBA, K.; MINAEI, S.; GÖKNAR, I. New Low-Voltage Low-Power VM All-Pass Filter Using Current Follower with Non- Unity Gain. In Proceedings of the 2014 IEEE 57th International Midwest Symposium on Circuits and Systems (MWSCAS 2014). College Station, Texas, USA: 2014. p. 571-574. ISBN: 978-1-4799-4132- 2.
HERENCSÁR, N.; KOTON, J.; VRBA, K.; CICEKOGLU, O. Low-Voltage Fully Cascadable Resistorless Transadmittance-Mode All- Pass Filter. In Proceedings of the 2014 IEEE 57th International Midwest Symposium on Circuits and Systems (MWSCAS 2014). College Station, Texas, USA: 2014. p. 185-188. ISBN: 978-1-4799-4132- 2.
JEŘÁBEK, J.; ŠOTNER, R.; HERENCSÁR, N.; JAIKLA, W.; VRBA, K. Behavioral Model for Z- copy Voltage Controlled Current Follower Differential Input Transconductance Amplifier and Its Features. In Proceedings of 2014 37th International Conference on Telecommunications and Signal Processing (TSP). 2014. p. 391-395. ISBN: 978-80-214-4983- 1.
ŠOTNER, R.; JEŘÁBEK, J.; HERENCSÁR, N.; HORNG, J.; VRBA, K. Electronically Linearly Voltage Controlled Second-Order Harmonic Oscillator With Multiples of pi/ 4 Phase Shifts. In Proceedings of the 37th International Conference on Telecommunications and Signal Processing 2014. 2014. p. 396-400. ISBN: 978-80-214-4983- 1.
HERENCSÁR, N.; MINAEI, S.; KOTON, J.; VRBA, K. Voltage-Mode All-Pass Filter Design Using Simple CMOS Transconductor: Non- Ideal Case Study. In Proceedings of the 2014 37th International Conference on Telecommunications and Signal Processing (TSP). Berlin, Germany: 2014. p. 1-4. ISBN: 978-80-214-4983- 1.
KUBÁNEK, D.; VRBA, K.; USHAKOV, P. Oscillator with Current Conveyors and Fractional Capacitors. In Proceedings of the Fourth Forum of Young Researchers. Izhevsk, Russia: Publishing House of Kalashnikov ISTU, 2014. p. 343-347. ISBN: 978-5-7526-0649- 6.
ŠOTNER, R.; JEŘÁBEK, J.; HERENCSÁR, N.; PROKOP, R.; VRBA, K.; DOSTÁL, T. Resistor-less First- Order Filter Design with Electronical Reconfiguration of its Transfer Function. In Proceedings of the 24th International Conference Radioelektronika 2014. 2014. p. 63-66. ISBN: 978-1-4799-3715- 8.
ŠOTNER, R.; JEŘÁBEK, J.; PETRŽELA, J.; VRBA, K.; DOSTÁL, T. Design of Fully Adjustable Solution of Band-Reject/All- Pass Filter Transfer Function Using Signal Flow Graph Approach. In Proceedings of the 24th International Conference Radioelektronika 2014. 2014. p. 67-70. ISBN: 978-1-4799-3715- 8.
ŠOTNER, R.; JEŘÁBEK, J.; HERENCSÁR, N.; PROKOP, R.; VRBA, K.; PETRŽELA, J.; DOSTÁL, T. Simply Adjustable Triangular and Square Wave Generator Employing Controlled Gain Current and Differential Voltage Amplifier. In Proceedings of the 23th international conference Radioelektronika 2013, April 16-17, Pardubice (MAREW 2013 - Microwave and Radio Electronics Week 2013). Pardubice: University of Pardubice, Studentska 95, 532 10, Pardubice, Czech Republic, 2013. p. 111-116. ISBN: 978-1-4673-5517- 9.
HERENCSÁR, N.; KOTON, J.; VRBA, K.; CICEKOGLU, O. New Current-Mode All-Pass Filter With Grounded Capacitor Based on Gain- Variable CCIII. In Proceedings of the IEEE Region 8 AFRICON 2013. IEEE, 2013. p. 559-562. ISBN: 978-1-4673-5943- 6.
KUBÁNEK, D.; KHATEB, F.; VRBA, K. Current-Controlled Square/Triangular Wave Generator with MO- CCDVCC. In 36th International Conference on Telecommunications and Signal Processing. Rome, Italy: Asszisztencia Szervezo Kft., 2013. p. 444-448. ISBN: 978-1-4799-0403- 7.
JEŘÁBEK, J.; ŠOTNER, R.; VRBA, K. General Current- Mode Filtering Structure with Controllable Current Active Elements. In Proceedings of the 36th International Conference on Telecommunications and Signal Processing (TSP 2013). 2013. p. 402-406. ISBN: 978-1-4799-0403- 7.
ŠOTNER, R.; JEŘÁBEK, J.; HERENCSÁR, N.; LAHIRI, A.; PETRŽELA, J.; VRBA, K. Practical Aspects of Operation of Simple Triangular and Square Wave Generator Employing Diamond Transistor and Controllable Amplifiers. In Proceedings of the 36th International Conference on Telecommunications and Signal Processing (TSP 2013). 2013. p. 431-435. ISBN: 978-1-4799-0403- 7.
ŠOTNER, R.; JEŘÁBEK, J.; GÖTTHANS, T.; PROKOP, R.; DOSTÁL, T.; VRBA, K. Controlled Gain Current and Differential Voltage Amplifier and Study of Its Application in Simple Adjustable Oscillator. In Proceedings of the 36th International Conference on Telecommunications and Signal Processing (TSP 2013). 2013. p. 407-411. ISBN: 978-1-4799-0403- 7.
HERENCSÁR, N.; KOTON, J.; VRBA, K. Low-Voltage CMOS-RC Fully Cascadable Transadmittance-Mode All- Pass Filter. In Proceedings of the 2013 36th International Conference on Telecommunications and Signal Processing (TSP). 2013. p. 389-391. ISBN: 978-1-4799-0403- 7.
ŠOTNER, R.; JEŘÁBEK, J.; HERENCSÁR, N.; PETRŽELA, J.; VRBA, K.; KINCL, Z. Tunable Oscillator Derived from Colpitts Structure with Simply Controllable Condition of Oscillation and Synthetic Inductor Based on Current Amplifier and Voltage Differencing Transconductance Amplifier. In Proceeding of the 8th International Conference on Electrical and Electronics Engineering. The Chamber of Electrical Engineers Bursa Branch (EMO), 2013. p. 21-25. ISBN: 978-605-01-0504- 9.
JEŘÁBEK, J.; ŠOTNER, R.; KINCL, Z.; DOSTÁL, T.; VRBA, K. Study of Practical Problems in Two-Loop CCTA Based Biquad: Finite Attenuations in Stop Bands. In Proceeding of the 8th International Conference on Electrical and Electronics Engineering. The Chamber of Electrical Engineers Bursa Branch (EMO), 2013. p. 40-44. ISBN: 978-605-01-0504- 9.
HERENCSÁR, N.; ŠOTNER, R.; METIN, B.; KOTON, J.; VRBA, K. VDDDA - New 'Voltage Differencing' Device for Analog Signal Processing. In Proceeding of the 8th International Conference on Electrical and Electronics Engineering. Bursa, Turkey: The Chamber of Electrical Engineers Bursa Branch (EMO), 2013. p. 17-20. ISBN: 978-605-01-0504- 9.
KOTON, J.; VRBA, K.; HERENCSÁR, N. Fast Voltage-Mode Full- Wave Rectifier Using CCII and DXCCII. In Proc. 8th Int. Conf. Electrical and Electronics Engineering - ELECO 2013. Turecko: 2013. p. 49-52. ISBN: 978-605-01-0504- 9.
KOTON, J.; HERENCSÁR, N.; VRBA, K.; METIN, B. The VDDDA in Multifunction Filter With Mutually Independent Q and w0 Control Feature. In Proc. 8th Int. Conf. Electrical and Electronics Engineering - ELECO 2013. Turecko: 2013. p. 53-56. ISBN: 978-605-01-0504- 9.
ŠOTNER, R.; JEŘÁBEK, J.; HERENCSÁR, N.; DOSTÁL, T.; VRBA, K. Electronically Adjustable Modification of CFA: Double Current Controlled CFA (DCC-CFA). In Proceedings of the 35th International Conference on Telecommunications and Signal Processing (TSP 2012). 2012. p. 401-405. ISBN: 978-1-4673-1116- 8.
JEŘÁBEK, J.; ŠOTNER, R.; VRBA, K. Comparison of the SITO Current-Mode Universal Filters Using Multiple- Output Current Followers. In Proceedings of the 35th International Conference on Telecommunications and Signal Processing (TSP 2012). 2012. p. 406-410. ISBN: 978-1-4673-1116- 8.
HERENCSÁR, N.; KOTON, J.; VRBA, K.; METIN, B. Fully Cascadable Dual-Mode All- Pass Filter Based on Single DBTA. In Proceedings of the 2012 35th International Conference on Telecommunications and Signal Processing (TSP). Prague, Czech Republic: 2012. p. 374-377. ISBN: 978-1-4673-1116- 8.
HERENCSÁR, N.; KOTON, J.; VRBA, K.; LAHIRI, A.; METIN, B. Novel Dual-Mode Electronically Tunable All-Pass Filter Using Voltage Gain- Controlled MCFOA. In Proceeding of the 13th International Conference on Optimization of Electrical and Electronic Equipment (OPTIM 2012). Brasov: 2012. p. 1199-1202. ISBN: 978-1-4673-1653- 8.
KOTON, J.; HERENCSÁR, N.; VRBA, K.; METIN, B. Current- and Voltage-Mode Third- Order Quadrature Oscillator. In Proc. 13th Int. Conf. Optimization of Electrical and Electronic Equipment (OPTIM 2012). Brasov: 2012. p. 1203-1206. ISBN: 978-1-4673-1653- 8.
HERENCSÁR, N.; KOTON, J.; VRBA, K.; METIN, B.; CICEKOGLU, O. Low-Voltage Two NMOS IVB-Based Voltage-Mode First-Order All- Pass Filter With Tuning. In Proceedings of the 11th International Conference on Development and Application Systems (DAS 2012). Suceava: 2012. p. 119-121. ISBN: 978-606-571-815- 9.
ŠOTNER, R.; HERENCSÁR, N.; JEŘÁBEK, J.; KOTON, J.; DOSTÁL, T.; VRBA, K. Quadrature Oscillator Based on Modified Double Current Controlled Current Feedback Amplifier. In Proceedings of 22nd International Conference Radioelektronika 2012, April 17-18. 2012. Brno: Dept. of Radio electronics, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech Republic, 2012. p. 275-278. ISBN: 978-80-214-4468- 3.
HERENCSÁR, N.; LAHIRI, A.; KOTON, J.; VRBA, K.; ŠOTNER, R. New Floating Lossless Inductance Simulator Using Z- copy Current Follower Transconductance Amplifiers. In Proceedings of the 22nd International Conference Radioelektronika 2012. Brno: 2012. p. 93-96. ISBN: 978-80-214-4468- 3.
JEŘÁBEK, J.; VRBA, K. Comparison of the Fully-Differential and Single- Ended Solutions of the Frequency Filter with Current Followers and Adjustable Current Amplifier. In ICN 2012 : The Eleventh International Conference on Networks. Reunion, France: IARIA, 2012. p. 50-54. ISBN: 978-1-61208-183- 0.
HERENCSÁR, N.; KOTON, J.; VRBA, K.; LAHIRI, A. Single GCFDITA and Grounded Passive Elements Based General Topology for Analog Signal Processing Applications. In Proceedings of the Eleventh International Conference on Networks - ICN 2012. 2012. p. 59-62. ISBN: 978-1-61208-183- 0.