@inproceedings{AndreiDoernerBengtssonetal., author = {Andrei, Cristina and D{\"o}rner, Ralf and Bengtsson, Olof and Chevtchenko, Serguei A. and Heinrich, Wolfgang and Rudolph, Matthias}, title = {Highly Linear X-Band GaN-Based Low-Noise Amplifier}, series = {Signals, Systems, and Electronics (ISSSE), 2012 International Symposium on , Potsdam}, booktitle = {Signals, Systems, and Electronics (ISSSE), 2012 International Symposium on , Potsdam}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4673-4454-8}, language = {en} } @inproceedings{AndreiBengtssonDoerneretal., author = {Andrei, Cristina and Bengtsson, Olof and D{\"o}rner, Ralf and Chevtchenko, Serguei A. and Heinrich, Wolfgang and Rudolph, Matthias}, title = {Dynamic behaviour of a Low-Noise Amplifier GaN MMIC under input power overdrive}, series = {Proceedings of 45th European Microwave Conference, Paris 2015}, booktitle = {Proceedings of 45th European Microwave Conference, Paris 2015}, publisher = {IEEE}, doi = {10.1109/EuMC.2015.7345742}, pages = {231 -- 234}, language = {en} } @inproceedings{AndreiBengtssonDoerneretal., author = {Andrei, Cristina and Bengtsson, Olof and D{\"o}rner, Ralf and Chevtchenko, Serguei A. and Rudolph, Matthias}, title = {Robust Stacked GaN-Based Low-Noise Amplifier MMIC for Receiver Applications}, series = {IEEE MTT-S International Microwave Symposium (IMS), 17-22 May 2015}, booktitle = {IEEE MTT-S International Microwave Symposium (IMS), 17-22 May 2015}, publisher = {IEEE}, doi = {10.1109/MWSYM.2015.7166766}, pages = {4}, language = {en} } @inproceedings{RudolphAndreiDoerneretal., author = {Rudolph, Matthias and Andrei, Cristina and D{\"o}rner, Ralf and Chevtchenko, Serguei A. and Heinrich, Wolfgang}, title = {Noise in GaN HEMTs and Circuits}, series = {24th International Conference on Noise and Fluctuations (ICNF), Vilnius, Lithuania, June 20-23, 2017}, booktitle = {24th International Conference on Noise and Fluctuations (ICNF), Vilnius, Lithuania, June 20-23, 2017}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-5090-2760-6}, doi = {10.1109/ICNF.2017.7985978}, pages = {1 -- 4}, language = {en} } @inproceedings{AndreiDoernerChevtchenkoetal., author = {Andrei, Cristina and D{\"o}rner, Ralf and Chevtchenko, Serguei A. and Heinrich, Wolfgang and Rudolph, Matthias}, title = {On the Optimization of GaN HEMT Layout for Highly Rugged Low-Noise Amplifier Design}, series = {12th European Microwave Integrated Circuits Conference (EuMIC), 8-10 Oct. 2017, Nuremberg, Germany}, booktitle = {12th European Microwave Integrated Circuits Conference (EuMIC), 8-10 Oct. 2017, Nuremberg, Germany}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-2-87487-048-4}, doi = {10.23919/EuMIC.2017.8230705}, pages = {244 -- 247}, language = {en} } @misc{BeleniotisChevtchenkoRudolph, author = {Beleniotis, Petros and Chevtchenko, Serguei A. and Rudolph, Matthias}, title = {Statistical Medeling of GaN HEMTs by Direct Transfer of Veriations to Model Parameters}, series = {16th European Microwave Integrated Circuits Conference (EuMIC), 03-04 April 2022, London, United Kingdom}, journal = {16th European Microwave Integrated Circuits Conference (EuMIC), 03-04 April 2022, London, United Kingdom}, isbn = {978-2-87487-064-4}, doi = {10.23919/EuMIC50153.2022.9783780}, pages = {63 -- 66}, language = {en} } @misc{RaoWentzelHoffmannetal., author = {Rao, Megha Krishnaji and Wentzel, Andreas and Hoffmann, Thomas and Schellhase, Lars and Chevtchenko, Serguei A. and Rudolph, Matthias}, title = {Digital GaN-based transceiver module for future green 5G networks}, series = {2024 54th European Microwave Conference (EuMC)}, journal = {2024 54th European Microwave Conference (EuMC)}, publisher = {IEEE}, doi = {10.23919/EuMC61614.2024.10732423}, pages = {136 -- 139}, language = {en} } @misc{KauleLuoChevtchenkoetal., author = {Kaule, Evelyne and Luo, Peng and Chevtchenko, Serguei A. and Andrei, Cristina and Rudolph, Matthias}, title = {Analysis for the optimization of a rugged GaN low-noise amplifier MMIC with a compact stacked first amplifier stage}, series = {2024 IEEE International Conference on Microwaves, Communications, Antennas, Biomedical Engineering and Electronic Systems (COMCAS)}, journal = {2024 IEEE International Conference on Microwaves, Communications, Antennas, Biomedical Engineering and Electronic Systems (COMCAS)}, publisher = {IEEE}, doi = {10.1109/COMCAS58210.2024.10666226}, pages = {1 -- 4}, language = {en} } @misc{BeleniotisSchniederChevtchenkoetal., author = {Beleniotis, Petros and Schnieder, Frank and Chevtchenko, Serguei A. and Rudolph, Matthias}, title = {Localization of Trapping Effects in GaN HEMTs with Pulsed S-parameters and Compact Models}, series = {17th European Microwave Integrated Circuits Conference (EuMIC)}, journal = {17th European Microwave Integrated Circuits Conference (EuMIC)}, isbn = {978-2-87487-070-5}, doi = {10.23919/EuMIC54520.2022.9923511}, pages = {149 -- 152}, language = {de} } @misc{KauleLuoChevtchenkoetal., author = {Kaule, Evelyne and Luo, Peng and Chevtchenko, Serguei A. and Rudolph, Matthias and Andrei, Cristina}, title = {Compact Stacked Rugged GaN Low-Noise Amplifier MMIC under Input Power Overdrive Condition}, series = {18th European Microwave Integrated Circuits Conference (EuMIC),18-19 September 2023, Berlin}, journal = {18th European Microwave Integrated Circuits Conference (EuMIC),18-19 September 2023, Berlin}, isbn = {978-2-87487-073-6}, doi = {10.23919/EuMIC58042.2023.10288650}, pages = {9 -- 12}, language = {en} } @misc{RaoDoernerChevtchenkoetal., author = {Rao, Megha Krishnaji and D{\"o}rner, Ralf and Chevtchenko, Serguei A. and Haque, Sanaul and Rudolph, Matthias}, title = {Common-Gate LNA MMIC With Switching Feature Using GaN-HEMT for 5G RF Front-Ende}, series = {IEEE Microwave and Wireless Technology Letters}, volume = {33}, journal = {IEEE Microwave and Wireless Technology Letters}, number = {10}, issn = {2771-9588}, doi = {10.1109/LMWT.2023.3306177}, pages = {1446 -- 1449}, language = {en} } @misc{BassalChevtchenkoSchniederetal., author = {Bassal, Amer and Chevtchenko, Serguei A. and Schnieder, Frank and Flisgen, Thomas and Bengtsson, Olof and Brunner, Frank and Hilt, Oliver}, title = {Impact of parasitic conductive interfaces on the DC and RF performance of GaN-on-GaN HEMTs}, series = {Physica status solidi (A). Applications and materials science}, journal = {Physica status solidi (A). Applications and materials science}, publisher = {Wiley}, address = {Hoboken, NJ}, doi = {10.1002/pssa.202500406}, pages = {1 -- 10}, abstract = {Radio frequency (RF) AlGaN/GaN high-electron-mobility transistors (HEMTs) on semi-insulating GaN substrates showed an unexpectedly low output power of ≤1.7 W mm⁻¹ and a power added efficiency (PAE) of ≤15\% for Vds = 20 V at 20 GHz, despite their good DC current densities (>1 A mm⁻¹) and minor trapping effects in pulsed characterization, comparable to GaN-on-SiC HEMTs. With theoretical calculations of Pout and PAE, and the detailed analysis of transistors and structures, a 1500 Ω/□ parasitic conductive interface (PCI) between the GaN substrate and the epitaxial layers was identified as a root cause. GaN substrates suffer from environmental Si contamination forming such a PCI. It was first detected by eddy current measurements showing that the insulating GaN:Fe buffer and GaN:Mn substrate did not effectively suppress the PCI. Nevertheless, it was effectively isolated by the GaN:Fe buffer to maintain a good DC performance for GaN-on-GaN HEMTs and allowing for a record gm-max of 535 mS mm⁻¹. The S-parameters confirmed this and indicated that the PCI causes a feed-back effect, reducing the k-point and fmax. Furthermore, loading effects were revealed on the ports of the HEMTs due to the PCI's resistive nature, and coplanar waveguide measurements showed 5 dB mm⁻¹ of propagation loss and severe changes in the characteristic impedance.}, language = {en} } @misc{KrishnajiRaoWentzelHoffmannetal., author = {Krishnaji Rao, Megha and Wentzel, Andreas and Hoffmann, Thomas and Schellhase, Lars and A. Chevtchenko, Serguei and Yazdani, Hossein and Rudolph, Matthias}, title = {Digital GaN-based transceiver architectures for sustainable 5G networks}, series = {International journal of microwave and wireless technologies}, journal = {International journal of microwave and wireless technologies}, publisher = {Cambridge University Press (CUP)}, address = {Cambridge}, issn = {1759-0787}, doi = {10.1017/S1759078725102262}, pages = {1 -- 9}, abstract = {This paper presents two distinct configurations of a GaN-based digital transceiver (TRx) to evaluate their performance and integration efficiency. The first configuration, features a novel low-noise amplifier with integrated switching capability (LNAiS) and a digital class-E power amplifier (PA) on a single compact chip. The LNAiS eliminates the need for an external antenna switch, reducing module complexity and chip size while maintaining high performance. It achieves a gain of 12.7 dB and a noise figure of 3 dB at 4.7 GHz in Rx mode and provides over 20 dB isolation in Tx mode across 4.7-7.4 GHz. The digital PA demonstrates flexibility and efficiency, achieving 46\% and 23\% efficiencies for 20 MHz LTE and OFDM signals, respectively, and 22\% for a 240 MHz OFDM signal with 10 dB PAPR. The second configuration integrates the same concept of digital PA with a standard LNA and an SPDT switch (LNAsS), achieving a gain of 24.8 dB and a noise figure of 2.65 dB at 4.2 GHz. This work highlights the trade-offs between these two architectures and demonstrates that the LNAiS-based approach drives the development of greener, more flexible, compact,lower-complexity, and cost-effective transceivers for 5G networks.}, language = {en} }