Creating and sharing knowledge for telecommunications
... João Manuel Torres Caldinhas Simões Vaz

Senior Researcher

João Vaz

Academic position: Assistant Professor
Joining date: 04-10-2002
Roles in IT: Senior Researcher
Scientific Area: Wireless Communications
Group: Wireless Circuits – Lx

Email: Send Email
Address: IT – Lisboa
Instituto Superior Técnico - Torre Norte - Piso 10
Av. Rovisco Pais, 1
1049 - 001 Lisboa
Tel: +351 21 841 84 54
Fax: +351 21 841 84 72


Scientific Achievements

  • PhD, Instituto Superior Técnico, 23-07-1998
  • MSc, Instituto Superior Técnico, 01-03-1991
  • Licenciatura, Instituto Superior Técnico, 30-09-1987
  • CMOS high-efficiency power amplifiers
  • CMOS frequency analog and digital synthesizers
  • CMOS and SiGe transceivers design
  • Ultra Low Power Design
  • CMOS Wireless Sensors for IoT
  • Monolhitic passive components design and characterization
  • Instituto Superior Técnico, 28-07-1998, Assistant Professor
  • IEEE - Institute of Electrical and Electronics Engineers, 01-12-1996, Senior Member
  • Ordem dos Engenheiros, 01-12-1987, Sócio
Supervision of theses
Co-Supervision of theses
  • P. M. Santos, L. Mendes, J. Vaz, HJQ Quaresma, Chapter 8: Layout strategies for substrate crosstalk reduction in low cost CMOS processes, Chapter in, Noise Coupling in System-on-Chip, Thomas Noulis, CRC-Taylor & Francis Group, Boca Raton, 2017
  • EJB Baptista, K. Buisman, J. Vaz, C. Fager, Analysis of Thermal Coupling Effects in Integrated MIMO Transmitters, IEEE International Microwave Symposium IMS, Honolulu, United States, Vol., pp. -, June, 2017 | BibTex
  • M. Pereira, J. C. Costa, M. Santos, J. Vaz, An 1µA Voltage Reference Circuit With High PSRR and Temperature Compensation, Conference on Design of Circuits and Integrated Systems DCIS, Lisbon, Portugal, Vol. 1, pp. 1 - 1, November, 2015 | BibTex
  • M. Pereira, J. Vaz, C.A. Leme, J. T. Sousa, J. Costa Freire, An Ultra-Low Power Low-IF GFSK Demodulator for Bluetooth-LE applications, IEEE International Symp. on Circuits and Systems - ISCAS, Lisbon, Portugal, Vol. 1, pp. 1226 - 1229, May, 2015,
    | Abstract
    | BibTex
  • P.G. Pereira, M. Pereira, R.M.F. Alves, A.M.C. Costa, J. Vaz, C.A. Leme, All-Digital Phase Locked Loop for Bluetooth Low Energy Transmitters, Conf. on Design of Circuits and Integrated Systems, San Sebastian, Spain, Vol. 1, pp. 1 - 1, November, 2013,
    | Abstract
    | BibTex
  • M. Pereira, J. Vaz, A 20 dBm Fully Integrated Single Stage CMOS Power Amplifier with 40 dB Power Gain, Conf. on Telecommunications - ConfTele, Castelo Branco, Portugal, Vol. 1, pp. 175 - 178, May, 2013,
    | Abstract
    | BibTex
  • V. Canosa, M. Pereira, P. Gomes, J. Vaz, J. Costa Freire, Fully Integrated Switched Dual-Band CMOS LNA for 802.11b/g WLAN and WiMAX applications, European Microwave Integrated Circuits - EuMIC, Amsterdam, Netherlands, Vol., pp. 397 - 400, October, 2012,
    | Abstract
    | BibTex
  • V. Canosa, M. Pereira, P. Gomes, J. Vaz, J. Costa Freire, Fully integrated switched dual-band CMOS LNA for 802.11b/g WLAN and WiMAX applications, European Microwave Integrated Circuits - EuMIC, Amsterdam, Netherlands, Vol., pp. 397 - 400, October, 2012 | BibTex
  • V. Canosa, J. Vaz, M. Pereira, Switched Dual-band CMOS LNA for 802.11b/g WLAN and WiMAX Applications, Conf. on Design of Circuits and Integrated Systems, Albufeira, Portugal, Vol., pp. 235 - 240, November, 2011 | BibTex
  • M. Pereira, J. Vaz, V. Canosa, A 2.45 GHz 30 dBm Differential 0.18 μm CMOS Class-E Power Amplifier with 42% PAE, Conf. on Design of Circuits and Integrated Systems, Albufeira, Portugal, Vol., pp. 381 - 385, November, 2011 | BibTex
  • R. F. Ribeiro Ribeiro, L. Mendes, J. Vaz, M. Rosário, J. Costa Freire, A 130 nm CMOS LNA for 30 GHz Applications, Conf. on Telecommunications - ConfTele, Lisbon, Portugal, Vol. --, pp. -- - --, April, 2011 | BibTex
  • E. S. Pires Pires, L. Mendes, P. B. Oliveira, J. A. Machado, J. Vaz, M. Rosário, Maximin Spreading Algorithm, IEEE World Congress on Computational Intelligence - WCCI, Barcelona, Spain, Vol., pp. -- - --, July, 2010 | BibTex
  • F. Azevedo, L. Mendes, V. Fialho, J. Vaz, F. Fortes, M. Rosário, A 1.8V/5GHz CMOS WLAN Low Noise Amplifier Integrated with Active BALUN, Conf. on Telecommunications - ConfTele, Santa Maria da Feira, Portugal, Vol. n, pp. n - n, May, 2009,
    | Abstract
    | BibTex
  • J. Vaz, V. Fialho, A 2.4GHz CMOS Integer-N Phase-Locked Loop, Conf. on Telecommunications - ConfTele, Santa Maria da Feira, Portugal, Vol. 0, pp. 0 - 0, May, 2009 | BibTex
  • F. Azevedo, L. Mendes, J. Vaz, F. Fortes, M. Rosário, A 5GHz/1.8V Low Power CMOS Low-Noise Amplifier, Asia Pacific Microwave Conf. - APMC, Hong Kong, China, Vol. 000, pp. 000 - 000, December, 2008,
    | Abstract
    | BibTex
  • F. Azevedo, L. Mendes, J. Vaz, F. Fortes, M. Rosário, A 5GHz/1.8V CMOS Active Balun Integrated With LNA, Asia Pacific Microwave Conf. - APMC, Hong Kong, China, Vol. na, pp. na - na, December, 2008,
    | Abstract
    | BibTex
  • L. Mendes, J. Vaz, M. Rosário, A Low Power Low Phase Noise Wide Switched Tuned Band LC VCO for S Band Applications, Asia Pacific Microwave Conf. - APMC, Hong Kong – Macau, Hong Kong, Vol. --, pp. -- - --, December, 2008 | BibTex
  • L. Mendes, E. S. Pires Pires, J. Vaz, M. Rosário, P. B. Oliveira, Automated Synthesis Procedure of RF Discrete Tuning Differential Capacitance Circuits, Asia Pacific Microwave Conf. - APMC, Hong Kong – Macau, Hong Kong, Vol. --, pp. -- - --, December, 2008 | BibTex
  • F. Azevedo, L. Mendes, J. Vaz, F. Fortes, M. Rosário, A Low Power 1.8V/5GHz Monolithic Low-Noise Amplifier, Jornadas de Engenharia de Electrónica e Telecomunicações e de Computadores do ISEL, Lisbon, Portugal, Vol. na, pp. na - na, November, 2008,
    | Abstract
    | BibTex
  • E. S. Pires Pires, L. Mendes, P. B. Oliveira, J. Vaz, M. Rosário, Single-Objective Pareto Front Optimization: Application to RF Circuit Design, Genetic and Evolutionary Computation Conf. - GECCO, Atlanta, United States, Vol. --, pp. -- - --, July, 2008 | BibTex
  • L. Mendes, E. S. Pires Pires, J. Vaz, M. Rosário, A High-Performance Digitally Controlled LC Oscillator for Ku-Band Applications, IEEE International Conf. on Electronics, Circuits and Systems, Marrakech, Morocco, Vol. --, pp. -- - --, December, 2007 | BibTex
  • L. Mendes, E. S. Pires Pires, J. Vaz, M. Rosário, An Evolutionary Synthesis Algorithm to Design Optimum Performance CMOS RFSSCAs, IEEE International Conf. on Electronics, Circuits and Systems, Marrakech, Morocco, Vol. --, pp. -- - --, December, 2007 | BibTex
  • J. Torres, J. Vaz, J. Costa Freire, 30GHz Amplifiers with 0.25ƒÝm SiGe BiCMOS, IEEE International Conf. on Electronics, Circuits and Systems, marrakesh, Morocco, Vol. I, pp. 0 - 0, December, 2007 | BibTex
  • F. Azevedo, F. Fortes, J. Vaz, M. Rosário, A Wideband CMOS LNA Integrated with Balun and Linear Digital Gain Control, IEEE International Conf. on Electronics, Circuits and Integrated Systems - ICECS, Marrakesh, Morocco, Vol. na, pp. na - na, December, 2007 | BibTex
  • E. S. Pires Pires, L. Mendes, P. B. Oliveira, J. A. Machado, N. M. Ferreira, J. Vaz, M. Rosário, Single-Objective MaxMin Sorting Scheme: Application to Radio Frequency Circuit Design, International Conf. on Electrical Engineering, Coimbra, Portugal, Vol. --, pp. -- - --, November, 2007 | BibTex
  • F. Azevedo, F. Fortes, J. Vaz, M. Rosário, A 1.7V Wideband CMOS Low Noise Amplifier with Linear Digital Gain Control, International Microwave and Optics Conf., Salvador BA, Brazil, Vol. na, pp. na - na, October, 2007 | BibTex
  • L. Mendes, E. S. Pires Pires, J. Vaz, M. Rosário, Automated Design of Radio-Frequency Single-Ended Switched Capacitor Arrays using Genetic Algorithms, Midwest Symp. on Circuits and Systems, Montréal, Canada, Vol. --, pp. -- - --, August, 2007 | BibTex
  • L. Mendes, J. Vaz, M. Rosário, Wide Tuning Band Low Phase Noise LC Voltage Controlled Oscillators Designed in Low Cost CMOS Technologies, Conf. on Telecommunications - ConfTele, Peniche, Portugal, Vol. --, pp. -- - --, May, 2007 | BibTex
  • G. St´Aubyn, J. Vaz, J. Costa Freire, Voltage Controlled Phase Shifters on CMOS Technology, Asia Pacific Microwave Conf. - APMC, Yokohama, Japan, Vol. 1, pp. 1 - 1, December, 2006 | BibTex
  • L. Mendes, J. Vaz, M. Rosário, Performance of Si-Integrated Wide-Band Single-Ended Switched Capacitor Arrays, IEEE International Conf. on Electronics, Circuits and Systems, Nice, France, Vol. --, pp. -- - --, December, 2006 | BibTex
  • J.O. Oliveira, J. Vaz, A CAD Oriented Method for Monolithic LC VCO Design, Conf. on Design of Circuits and Integrated Systems, Barcelona, Spain, Vol. 1, pp. 1 - 1, November, 2006 | BibTex
  • L. Mendes, J. Vaz, M. Rosário, Modeling of CMOS or BiCMOS Ultra-Wide-Band Single-Ended Switched Capacitor Arrays, Conf. on Design of Circuits and Integrated Systems, Barcelona, Spain, Vol. --, pp. -- - --, November, 2006 | BibTex
  • L. Mendes, J. Vaz, M. Rosário, A Closed-Form Input Admittance Solution for RF and Microwave Switched Capacitor Arrays, IEEE International Symp. on Circuits and Systems - ISCAS, San Juan, Puerto Rico, Vol. --, pp. -- - --, August, 2006 | BibTex
  • L. Mendes, J. Vaz, M. Rosário, Fully Integrated CMOS LC Voltage Controlled Oscillator for IEEE802.11a and HiperLAN2 WLAN Transceivers, International Conf. on Electrical Engineering, Coimbra, Portugal, Vol. na, pp. na - na, October, 2005 | BibTex
  • J. Bernardino, J. Vaz, High Q MMIC GaAs Active Filter for K Band Subsystems, Conf. on Telecommunications - ConfTele, Tomar, Portugal, Vol. na, pp. na - na, April, 2005 | BibTex
  • J. Vaz, M. Rosário, J. Costa Freire, Low Cost Si MMIC Design for RF Front Ends, Asia Pacific Microwave Conf. - APMC, New Delhi, India, Vol., pp. 1 - 2, December, 2004 | BibTex
  • J.O. Oliveira, J. Vaz, Oscilador Sinusoidal LC em Tecnologia BiCMOS para 2.4GHz, Workshop de Investigação e Desenvolvimento em Engenharia Electrotécnica e das Telecomunicações, Castelo Branco, Portugal, Vol. 1, pp. 1 - 1, February, 2004 | BibTex
  • M. Rosário, F. Le-Strat, P. Alleaume, J. Vaz, J. Schrotg, T. Mueller, J. Costa Freire, Low Cost LTCC Filters for a 30GHz Satellite System, European Microwave Conf. - EMC, Munique, Germany, Vol. 1, pp. 817 - 820, October, 2003 | BibTex
  • J.O. Oliveira, J. Vaz, A 2.4GHz LC-tuned VCO in BiCMOS technology, Conf. on Telecommunications - ConfTele, Aveiro, Portugal, Vol. 1, pp. 531 - 533, June, 2003 | BibTex

Currently running projects2

Acronym Name Funding Agency Start date Ending date
uFlexBat Batteryless energy supply system based on flexible organic photovoltaic cells IT/LA 01-12-2016 30-06-2019
WSN_EM Wireless Sensor Network for Environmental Monitoring FCT 01-09-2018 31-08-2021

Closed Projects11

Acronym Name Funding Agency Start date Ending date
ACTFIL Active filters IT/LA 01-01-2004 31-12-2005
AME Advanced Microelectronics Engineering ICEP 01-10-2002 22-10-2003
COMMET A COmplete analog front-end for 3G MultiMEdia Terminals ADI 01-11-2002 31-10-2005
Digital_PAs Digital_PAs - Digital RF Power Amplifiers for Wireless Applications FCT/PTDC 01-01-2009 01-06-2012
GALACTIC Innovative GaAs MMICs and Avanced LTCC packaging technologies for multicomponents Ka Band subsystems EU 01-01-2002 31-12-2004
IRFDCMOS Integration of high-frequency dc-dc converters in RF CMOS SoC IT/LA 01-09-2005 01-06-2008
LDMOSCA Low Distortion RF MOS Circuits Advances FCT/POCTI 01-01-2001 31-12-2002
NLRFCMOS Desenvolvimento de modelos não lineares de dispositivos para microondas e integração monolítica de circuitos não lineares em silício para telecomunicações CRUP 01-01-2003 31-12-2004
SiGeM Silicon Germanium MMICs for RF Front End Transceivers IT/LA 01-10-2005 01-07-2008
SWIPA Switching Mode Power Amplifiers for Wireless Communications IT/LA 01-11-2008 01-11-2010
WiFiRx Double-Band Multi_standard Frequency Front-End for WLAN aplications FCT/PTDC 01-09-2007 01-04-2010
  • J. Vaz, Docente Excelente, Considerado docente excelente relativamente à disciplina de Electrónica 1 leccionada no 2º semestre do ano lectivo 2010/11 no Mestrado Integrado em Engenharia Electrotécnica e Computadores., 01-01-2012
  • J. Costa Freire, G.M. Marques, W. Tam, J. Vaz, MMIC Lumped and Transversal Filter with LC Tuned Amplifiers, Best Poster at GAAS'99 (, 05-10-1999
  • J. Vaz, EMERGENT TECHNOLOGIES FOR FUTURE WIRELESS SYSTEMS, Portugal, Aveiro, 09-2012
  • J. Vaz, Introdução às Telecomunicações” (Ciência Viva no Laboratório – Ocupação Científica de Jovens nas Férias), Portugal, Lisboa, 07-2012
  • J. Vaz, High-Efficiency Radiofrequency Power Amplifiers, Macau, Macau, 07-2011
  • Invited to chair Session 7b of XX Conference on Design of Circuits and Integrated Systems, Lisboa, Portugal, Outubro 2005., Sessions Chairman, 2005
  • ETRI Journal
    2013, 1 review(s); 2005, 1 review(s);
  • IEEE Microwave Magazine
    2016, 1 review(s); 2012, 1 review(s); 2011, 1 review(s);
  • Integration, The VLSI Journal
    2016, 1 review(s);
  • IEEE Trans. on Circuits and Systems - II: Express Briefs
    2017, 1 review(s); 2016, 3 review(s);
  • IEEE Trans. on Microwave Theory and Tech.
    2014, 1 review(s); 2013, 1 review(s); 2010, 2 review(s); 2009, 1 review(s); 2008, 2 review(s); 2006, 1 review(s);
  • Wireless Personal Communications
    2011, 1 review(s);
  • IEEE International Symp. on Circuits and Systems - ISCAS
    2015, 1 review(s); 2014, 1 review(s); 2013, 1 review(s); 2012, 1 review(s); 2011, 1 review(s); 2009, 1 review(s);
  • Conf. on Design of Circuits and Integrated Systems
    2012, 1 review(s); 2009, 1 review(s); 2006, 1 review(s); 2005, 1 review(s); 2004, 1 review(s); 2003, 1 review(s); 2002, 1 review(s); 2000, 1 review(s); 1999, 1 review(s);
  • Conf. on Telecommunications - ConfTele
    2009, 1 review(s); 2005, 1 review(s); 2003, 1 review(s); 2001, 1 review(s);
  • International Conf. on Telecommunications - ICT
    2006, 1 review(s);