Luís Carlos Cótimos Nunes

Luis Nunes

Academic position:	Researcher
Joining date:	01-07-2017
Roles in IT:	Researcher
Thematic Line:	Wireless Technologies
Group:	Wireless Circuits – Av

Email: Send Email
Address: IT – Aveiro
Instituto de Telecomunicações
Campus Universitário de Santiago
P-3810-193 AVEIRO - PORTUGAL
Tel: +351 234 377 900
Fax: +351 234 377 901

https://www.orcid.org/0000-0003-2403-7126

SCOPUS SCHOLAR LinkedIn

26-10-2022

IT Researchers win EuMIC Prize

The paper entitled “A Simple Thermally Activated Trapping Model for AlGaN/GaN HEMTs” was awarded the 2022 EuMIC Prize.

28-04-2022

Catarina Belchior awarded 1st place in the Student Paper Competition at 2022 INMMiC

The winning paper proposes a methodology that enables the automation of the optimum impedance profiles’ selection in a power amplifier.

28-07-2020

João Gomes wins a $6,000 MTT-S fellowship

João is pursuing his PhD in Electrical Engineering, hosted by IT in Aveiro, under the supervision of José Pedro, Luís Nunes (both from IT/UA) and Nikolai Sobolev (UA). (see more)

João Gomes, a PhD student from the University of Aveiro (UA) and a research assistant with the IT in Aveiro has won a Graduate Student Fellowship in the amount of $6,000 sponsored by the largest scientific

Scientific Achievements

Degrees

PhD, Universidade de Aveiro, 10-12-2015
MSc, Universidade de Aveiro, 25-11-2010

Affiliations

Instituto de Telecomunicações, 03-07-2017, Research Assistant
IEEE - Institute of Electrical and Electronics Engineers, 07-01-2013, Member
IEEE Microwave Theory and Techniques Society, 07-01-2013, Member

Expertise Topics

Device Modeling
Nonlinear Distortion
Power Amplifier Design

Academic Activities

3Lecture courses

Programação em Matlab, Universidade de Aveiro, Engenharia Eletronica e Telecomunicações
Projecto Industrial, Universidade de Aveiro, Engenharia Eletronica e Telecomunicações
Aplicacionais para Ciencias e Engenharia, Universidade de Aveiro, MIEQui, LQui, MIEMec, LMOG, LBq, LBt, MIEFis, MIECiv, LGeo, MIEAmb, MIEMat

4Supervision of PhD theses

As Supervisor

Power Amplifier Design, Research Grant, Fernando Santos Bezerra, Expected conclusion 07-2023
AlGaN/GaN HEMT device modelling, Research Grant, KENJI VITÓRIA MORIMOTO, Expected conclusion 07-2023
Pulse I/V System for RF Power Transistors’ Characterization, Research Grant, João Pedro Azevedo Pinto, Concluded 07-2022

As Co-supervisor

Desenho de Amplificador de Potência usando Malhas de Adaptação Otimizadas, Research Grant, Inês Cristina Pereira Lopes, Concluded 06-2021

Publications

1Books

J. C. Pedro, D. Root, J. Xu, L. C. Nunes, Nonlinear Circuit Simualtion and Modeling - Fundamentals for Microwave Design, Cambridge University Press, New York, 2018,
| BibTex

18Papers in Journals

B. Gonzalez, L. C. Nunes, J. Gomes, J. C. Mendes, J. L. Jimenez, A Simple Method to Extract the Thermal Resistance of GaN HEMTs from De-trapping Characteristics, IEEE Electron Device Letters, Vol. 44, No. 6, pp. 891 - 894, June, 2023 | Full text (PDF 2 MBs) | BibTex
J. Gomes, L. C. Nunes, F. M. B. Barradas, J. C. Pedro, The Impact of Long-Term Memory Effects on the Linearizability of GaN HEMT-Based Power Amplifiers, IEEE Transactions on Microwave Theory and Techniques, Vol. 70, No. 2, pp. 1377 - 1390, February, 2022,
| Abstract | Full text (PDF 4 MBs) | BibTex
C. Gonçalves, F. M. B. Barradas, L. C. Nunes, P. M. Cabral, J. C. Pedro, Quasi-Load Insensitive Doherty PA Using Supply Voltage and Input Excitation Adaptation, IEEE Transactions on Microwave Theory and Techniques, Vol. 70, No. 1, pp. 779 - 789, January, 2022 | Full text (PDF 3 MBs) | BibTex
C. Belchior, L. C. Nunes, P. M. Cabral, J. C. Pedro, Automatic Methodology for Wideband Power Amplifier Design, IEEE Microwave and Wireless Components Letters, Vol. 31, No. 8, pp. 989 - 992, August, 2021,
| Abstract | Full text (PDF 1 MB) | BibTex
C. Gonçalves, F. M. B. Barradas, L. C. Nunes, P. M. Cabral, J. C. Pedro, A Compact Impedance Measurement Solution for Systems Operating in Load Varying Scenarios, IEEE Access, Vol. 9, No. -, pp. 38757 - 38766, March, 2021 | Full text (PDF 1 MB) | BibTex
J. Mendes, C. Belchior, D. Barros, F. M. B. Barradas, L. C. Nunes, P. M. Cabral, J. C. Pedro, New Transistor Behavioral Model Formulation Suitable for Doherty PA Design, IEEE Transactions on Microwave Theory and Techniques, Vol. 0, No. 0, pp. 1 - 1, February, 2021 | BibTex
C. Gonçalves, F. M. B. Barradas, L. C. Nunes, P. M. Cabral, J. C. Pedro, Dynamic Supply Voltage Control for PA Output Power Correction Under Variable Loading Scenarios, IEEE Transactions on Microwave Theory and Techniques, Vol. 69, No. 1, pp. 745 - 755, January, 2021 | Full text (PDF 3 MBs) | BibTex
P. M. Tomé, F. M. B. Barradas, L. C. Nunes, J. Gomes, T.R. Cunha, J. C. Pedro, Characterization, Modeling, and Compensation of the Dynamic Self-Biasing Behavior of GaN HEMT-Based Power Amplifiers, IEEE Transactions on Microwave Theory and Techniques, Vol. 0, No. 0, pp. 0 - 0, July, 2020,
| Abstract | BibTex
D. Barros, L. C. Nunes, P. M. Cabral, J. C. Pedro, Impact of the Input Baseband Terminations on the Efficiency of Wideband Power Amplifiers Under Concurrent Band Operation, IEEE Transactions on Microwave Theory and Techniques, Vol. 67, No. 12, pp. 5127 - 5138, December, 2019,
| Abstract | Full text (PDF 4 MBs) | BibTex
J. Gomes, L. C. Nunes, C. Gonçalves, J. C. Pedro, An Accurate Characterization of Capture Time Constants in GaN HEMTs, IEEE Transactions on Microwave Theory and Techniques, Vol. 67, No. 7, pp. 2465 - 2474, July, 2019 | BibTex
L. C. Nunes, D. Barros, P. M. Cabral, J. C. Pedro, Efficiency Degradation Analysis in Wideband Power Amplifiers, IEEE Transactions on Microwave Theory and Techniques, Vol. 66, No. 12, pp. 5640 - 5651, December, 2018 | BibTex
J. Gomes, L. C. Nunes, N. Sobolev, J. C. Pedro, Memristive Properties of GaN HEMTs Containing Deep‐Level Traps, Physica Status Solidi (B): Basic Research, Vol. 256, No. 5, pp. 1800387 - 1800387, December, 2018 | BibTex
C. Gonçalves, L. C. Nunes, P. M. Cabral, J. C. Pedro, Pulsed I/V and S-parameters measurement system for isodynamic characterization of power GaN HEMT transistors, Intrnl. Journal of RF and Microwave Computer-Aided Engineering, Vol. 28, No. 8, pp. e21515 - e21515, August, 2018 | BibTex
F. M. B. Barradas, L. C. Nunes, T.R. Cunha, P.M.L. Lavrador, P. M. Cabral, J. C. Pedro, Compensation of Long-Term Memory Effects on GaN HEMT-Based Power Amplifiers, IEEE Transactions on Microwave Theory and Techniques, Vol. 65, No. 9, pp. 3379 - 3388, March, 2017,
| Abstract | BibTex
P. M. Cabral, L. C. Nunes, T. R. Ressurreição, J. C. Pedro, Trapping behavior of GaN HEMTs and its implications on class B PA bias point selection, International Journal of Numerical Modelling: Electronic Networks, Devices and Fields, Vol. 30, No. 1, pp. 1 - 11, January, 2017 | BibTex
J. C. Pedro, L. C. Nunes, P. M. Cabral, A Simple Method to Estimate the Output Power and Efficiency Load-Pull Contours of Class B Power Amplifiers, IEEE Transactions on Microwave Theory and Techniques, Vol. 63, No. 4, pp. 1239 - 1249, April, 2015 | BibTex
F. M. B. Barradas, L. C. Nunes, J. C. Pedro, T.R. Cunha, P.M.L. Lavrador, P. M. Cabral, Accurate Linearization with Low-Complexity Models Using Cascaded Digital Predistortion Systems, IEEE Microwave Magazine, Vol. 16, No. 1, pp. 94 - 103, February, 2015 | BibTex
L. C. Nunes, P. M. Cabral, J. C. Pedro, AM/AM and AM/PM Distortion Generation Mechanisms in Si LDMOS and GaN HEMT Based RF Power Amplifiers, IEEE Transactions on Microwave Theory and Techniques, Vol. 62, No. 4, pp. 799 - 809, April, 2014 | BibTex

28Papers in Conferences

L. C. Nunes, J. Gomes, F. M. B. Barradas, J. C. Pedro, A Simple Thermally Activated Trapping Model for AlGaN/GaN HEMTs, European Microwave Integrated Circuits - EuMIC, rome, Italy, Vol., pp. -, September, 2022,
| Abstract | BibTex
J. Gomes, L. C. Nunes, J. C. Pedro, On the Drain-to-Source Capacitance of Microwave FETs in Triode Region, IEEE International Microwave Symposium IMS, Denver, United States, June, 2022 | Full text (PDF 444 KBs) | BibTex
J. Gomes, L. C. Nunes, F. M. B. Barradas, J. C. Pedro, A Qualitative Explanation of the AlGaN GaN HEMT Nonlinear Intrinsic Capacitances, Integrated Non-linear Microwave and Millimetre-wave Circuits Conf. - INMMIC, Cardiff, United Kingdom, April, 2022,
| Abstract | Full text (PDF 468 KBs) | BibTex
C. Belchior, L. C. Nunes, P. M. Cabral, J. C. Pedro, Output Impedance Profile Selection in Sequential LMBAs using an Automatic Method, International Workshop on Integrated Nonlinear Microwave and Millimeter-Wave Circuits - INMMIC, Cardiff, United Kingdom, April, 2022,
| Abstract | Full text (PDF 819 KBs) | BibTex
J. Gomes, L. C. Nunes, J. C. Pedro, Explaining the Different Time Constants Extracted from Low Frequency Y22 and IDS-DLTS on GaN HEMTs, IEEE International Microwave Symposium IMS, Los Angeles, CA, USA, United States, August, 2020,
| Abstract | BibTex
J. Gomes, L. C. Nunes, J. C. Pedro, Transient Pulsed S-Parameters for Trapping Characterization, International Workshop on Integrated Nonlinear Microwave and Millimeter-Wave Circuits - INMMIC, Cardiff, United Kingdom, July, 2020 | BibTex
P. M. Tomé, F. M. B. Barradas, L. C. Nunes, J. Gomes, T.R. Cunha, J. C. Pedro, A Transient Two-Tone RF Method for the Characterization of Electron Trapping Capture and Emission Dynamics in GaN HEMTs, IEEE International Microwave Symposium IMS, Los Angeles, United States, Vol., pp. 428 - 431, June, 2020,
| Abstract | BibTex
C. Gonçalves, F. M. B. Barradas, L. C. Nunes, P. M. Cabral, J. C. Pedro, Optimal Supply Voltage for PA Output Power Correction under Load Varying Scenarios, IEEE International Microwave Symposium IMS, Los Angeles, United States, June, 2020 | BibTex
L. C. Nunes, F. M. B. Barradas, D. Barros, P. M. Cabral, J. C. Pedro, Current Mode Outphasing Power Amplifier, IEEE International Microwave Symposium IMS, Boston, United States, June, 2019 | BibTex
D. Barros, L. C. Nunes, P. M. Cabral, J. C. Pedro, Impact of the Input Baseband Impedance on the Instantaneous Bandwidth of Wideband Power Amplifiers, IEEE International Microwave Symposium IMS, Boston, United States, June, 2019 | BibTex
J. Gomes, L. C. Nunes, C. Gonçalves, J. C. Pedro, Deep-Level Traps’ Capture Time Constant and its Impact on Nonlinear GaN HEMT Modeling, International Workshop on Integrated Nonlinear Microwave and Millimeter-Wave Circuits - INMMIC, Brive-la-Gaillarde, France, July, 2018 | BibTex
L. C. Nunes, D. Barros, P. M. Cabral, J. C. Pedro, Efficiency Degradation in Wideband Power Amplifiers, IEEE International Microwave Symposium IMS, Philadelphia, United States, June, 2018 | BibTex
L. C. Nunes, J. Gomes, P. M. Cabral, J. C. Pedro, A Simple Method to Extract Trapping Time Constants of GaN HEMTs, IEEE International Microwave Symposium IMS, Philadelphia, United States, June, 2018 | BibTex
C. Gonçalves, P. M. Cabral, L. C. Nunes, J. C. Pedro, Conservative Current and Charge Data Extracted from Pulsed S-Parameter Measurements for GaN HEMT PA Design, IEEE International Symp. on Microwave Theory and Tech., Hawaii, United States, June, 2017 | BibTex
P. M. Cabral, L. C. Nunes, J. C. Pedro, High Power Wireless Applications of Si and GaN Devices, Workshop on Compound Semiconductor Devices and Integrated Circuits held in Europe WOCSDICE, Aveiro, Portugal, Vol. .., pp. .. - .., June, 2016 | BibTex
L. C. Nunes, P. M. Cabral, J. C. Pedro, AM/PM distortion physical origins in Si LDMOS Doherty power amplifiers, IEEE International Microwave Theory and Tech. Symp., San Francisco, United States, May, 2016 | BibTex
L. C. Nunes, P. M. Cabral, J. C. Pedro, Impact of Trapping Effects on GaN HEMT Based Doherty PA Load-Pull Ratios, International Workshop on Integrated Nonlinear Microwave and Millimeter-Wave Circuits - INMMIC, Taormina, Italy, October, 2015 | BibTex
L. C. Nunes, P. M. Cabral, J. C. Pedro, LUT Based Behavioral Model for Doherty Power Amplifier Design, Conf. on Telecommunications - ConfTele, Aveiro, Portugal, September, 2015 | BibTex
L. C. Nunes, P. M. Cabral, J. C. Pedro, A New Nonlinear Model Extraction Methodology for GaN HEMTs Subject to Trapping Effects, IEEE International Microwave Theory and Tech. Symp., Phoenix, United States, May, 2015 | BibTex
J. C. Pedro, L. C. Nunes, P. M. Cabral, Soft compression and the origins of nonlinear behavior of GaN HEMTs, European Microwave Conf. - EMC, Roma, Italy, Vol. 1, pp. 1297 - 1300, October, 2014,
| Abstract | BibTex
J. C. Pedro, L. C. Nunes, Efficiency dependence on the load-pull ratio of a Doherty PA, IEEE International Symp. on Microwave Theory and Tech., Seatle, United States, Vol. 1, pp. 1 - 4, June, 2014,
| Abstract | BibTex
L. C. Nunes, P. M. Cabral, J. C. Pedro, AM/PM Distortion in GaN Doherty Power Amplifiers, IEEE International Microwave Theory and Tech. Symp., Tampa, United States, June, 2014 | BibTex
L. C. Nunes, P. M. Cabral, J. C. Pedro, Study of the GaN HEMT Doherty Power Amplifier Distortion, International Workshop on Integrated Nonlinear Microwave and Millimeter-Wave Circuits - INMMIC, Leuven, Belgium, April, 2014 | BibTex
T.R. Cunha, P. M. Cabral, L. C. Nunes, Characterizing power amplifier static AM/PM with spectrum analyzer measurements, IEEE International Conf. on Signals, Systems, Devices - SSD, Barcelona, Spain, Vol. 1, pp. 1 - 4, February, 2014 | BibTex
J. C. Pedro, L. C. Nunes, A Single-Ended Power Amplifier Behavioral Model for AM/AM and AM/PM Predictions, IEEE Topical Conf. on RF Power Amplifiers for Radio and Wireless Applications - PAWR, Newport Beach, United States, Vol. 1, pp. 79 - 81, January, 2014,
| Abstract | BibTex
J. C. Pedro, L. C. Nunes, P.M.L. Lavrador, A New Large-Signal Intermodulation and Spurious Analysis Tool, IEEE International Microwave Theory and Tech. Symp., Seattle, United States, Vol. 1, pp. 1 - 1, June, 2013 | BibTex
L. C. Nunes, P. M. Cabral, J. C. Pedro, A Physical Model of Power Amplifiers’ AM/AM and AM/PM Distortions and Their Internal Relationship, IEEE International Microwave Theory and Tech. Symp., Seatle, United States, June, 2013 | BibTex
L. C. Nunes, P. M. Cabral, J. C. Pedro, A large-signal physical model of the AM/PM characteristic of a RF power amplifier, Conf. on Telecommunications - ConfTele, Castelo Branco, Portugal, May, 2013 | BibTex

Projects

Currently running projects1

Acronym	Name	Funding Agency	Start date	Ending date
Joint-Lab	Huawei-IT-Aveiro Joint-Lab Research Program Agreement	Huawei Technologies Sweden	01-09-2020	31-08-2028

Closed Projects4

Acronym	Name	Funding Agency	Start date	Ending date
HLPA2MIMO	Highly Linear Power Amplifier for Massive MIMO	Ampleon	01-07-2016	01-06-2020
ROOSTER	Rooster - Solutions to Optimize Efficiency-Linearity in High Power Multi-Band MISO Power Amplifiers	Huawei Technologies Sweden	01-07-2016	01-06-2018
TUPP	Modeling of Power Amplifier Devices	Huawei Technologies Sweden	01-01-2018	01-12-2020
XiongJi	Wideband Power Amplifier Design Methodologies	Huawei Technologies Sweden	01-06-2019	31-08-2020

Other Scientific Achievements

6Awards

L. C. Nunes, J. Gomes, F. M. B. Barradas, J. C. Pedro, 2022 EuMIC Prize, Recognition as the best paper presented at the “17th European Microwave Integrated Circuits Conference (EuMIC)”, held in Milan, Italy, as part of the European Microwave Week 2022., 01-09-2022
C. Belchior, L. C. Nunes, P. M. Cabral, J. C. Pedro, 1st Place on the Best Student Paper Award INMMiC 2022, 1st place of the best student paper award for the paper "Output Impedance Profile Selection in Sequential LMBAs using an Automatic Method" presented at the International Workshop on Integrated Nonlinear Microwave and Millimetre-wave Circuits - 7-8/04/2022 - Cardiff, UK., 01-04-2022
J. Gomes, L. C. Nunes, J. C. Pedro, Best Student Paper Award INMMiC 2020 (Second Place), 2nd place of the best student paper award for the paper "Transient Pulsed S-Parameters for Trapping Characterization" presented at the International Workshop on Integrated Nonlinear Microwave and Millimetre-wave Circuits - VIRTUAL EVENT 16-17/07/2020 - Cardiff, UK, 01-07-2020
F. M. B. Barradas, L. C. Nunes, Power Amplifier Linearization Through Digital Pre-Distortion Student Design Competition, Second Place, Competition for the linearization of a Radio Frequency Power Amplifier through digital predistortion. The competition entailed the study, development and deployment in a laboratory environment of the best linearization algorithms. The competition was international and took place at IMS2015., 01-07-2015
F. M. B. Barradas, L. C. Nunes, Power Amplifier Linearization Through Digital Pre-Distortion Student Design Competition, Competition for the linearization of a Radio Frequency Power Amplifier through digital predistortion. The competition entailed the study, development and deployment in a laboratory environment of the best linearization algorithms. The competition was international and took place at IMS2014., 01-07-2014
T.R. Cunha, P. M. Cabral, L. C. Nunes, Characterizing power amplifier static AM/PM with spectrum analyzer measurements, Best Paper Award - CCSP-SSD'14, Best paper award for the paper ''Characterizing power amplifier static AM/PM with spectrum analyzer measurements'' presented at the IEEE 11th International Multi-Conference on Systems, Signals and Devices - Conference on Communication & Signal Processing, CCSP-SSD’14, Castelldefels-Barcelona, Spain, February 11-14, 2014., 01-02-2014, 01-02-2014

4Short Courses and Seminars

L. C. Nunes, J. C. Pedro, F. M. B. Barradas, P. M. Cabral, T.R. Cunha, RF Technology for Wireless Communications and Sensing, Portugal, Aveiro, 11-2022
L. C. Nunes, F. M. B. Barradas, C. Gonçalves, J. Gomes, P. M. Tomé, T.R. Cunha, P. M. Cabral, J. C. Pedro, Long-Term Memory Effects in GaN Devices: From Modeling to Compensation, Spain, 09-2018
F. M. B. Barradas, T.R. Cunha, P. M. Tomé, P.M.L. Lavrador, P. M. Cabral, L. C. Nunes, J. C. Pedro, Prediction and Compensation of PA Linearity and Efficiency in MIMO scenarios, Spain, Madrid, 09-2018
T.R. Cunha, P. M. Cabral, L. C. Nunes, F. M. B. Barradas, J. C. Pedro, Wideband power amplifier linearization: from active device distortion to DPD compensation, United States, Austin, TX, 01-2016

Other Contributions

10Refereeing Journals

IEEE Transactions on Microwave Theory and Techniques
2022, 6 review(s); 2021, 3 review(s); 2020, 2 review(s); 2019, 7 review(s); 2018, 3 review(s); 2017, 2 review(s); 2016, 1 review(s); 2015, 1 review(s); 2014, 1 review(s);
IEEE Transactions on Power Electronics
2017, 1 review(s);
Intrnl. Journal of RF and Microwave Computer-Aided Engineering
2022, 2 review(s); 2021, 2 review(s); 2020, 7 review(s); 2019, 6 review(s);
IEEE Microwave and Wireless Components Letters
2021, 1 review(s); 2020, 3 review(s);
IEEE Access
2022, 2 review(s); 2021, 1 review(s); 2020, 3 review(s);
power electronic devices and components
2021, 1 review(s);
Remote Sensing
2021, 2 review(s);
Electronics (Switzerland)
2022, 2 review(s); 2021, 1 review(s);
International Journal of Microwave and Wireless Technologies
2022, 1 review(s);
International Journal of Numerical Modelling: Electronic Networks, Devices and Fields
2022, 3 review(s);

1Refereeing Conferences

European Microwave Week/European Microwave Conf.
2022, 1 review(s); 2021, 1 review(s);

IT Member Profile

Luis Nunes

26-10-2022

IT Researchers win EuMIC Prize

28-04-2022

Catarina Belchior awarded 1st place in the Student Paper Competition at 2022 INMMiC

28-07-2020

João Gomes wins a $6,000 MTT-S fellowship

Scientific Achievements

As Supervisor

As Co-supervisor

As Supervisor

As Co-supervisor

As Supervisor

As Co-supervisor

Currently running projects1

Closed Projects4