@misc{RaoBeleniotisHoffmannetal., author = {Rao, Megha Krishnaji and Beleniotis, Petros and Hoffmann, Thomas and Yazdani, Hossein and Wentzel, Andreas and Rudolph, Matthias}, title = {Switch-integrated GaN LNAs : a technology-focused analysis}, series = {2025 20th European Microwave Integrated Circuits Conference (EuMIC)}, journal = {2025 20th European Microwave Integrated Circuits Conference (EuMIC)}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-2-87487-082-8}, doi = {10.23919/EuMIC65284.2025.11234676}, pages = {29 -- 32}, abstract = {This paper presents the first circuit-level analysis of a two-stage GaN-HEMT LNA with an integrated switch, comparing two distinct technologies: one with a standard passivation layer (Type A) and another featuring an advanced passivation layer (Type B). Through a detailed evaluation of their performance in both amplification and isolation modes, the study highlights Type B as a significant advancement over Type A. Leveraging technological enhancements, including an improved passivation layer and slightly optimized component matching, Type B demonstrates superior performance. The results are compelling, with Type B achieving a gain of 19 dB, a low noise figure of 1.17dB, and small-signal isolation exceeding 30 dBm at 5.2 GHz. These achievements establish Type B as a formidable option for future 5G telecommunication systems, offering a performance that challenges traditional designs that use separate switches.}, language = {en} } @misc{OkochaAndreiRudolph, author = {Okocha, Jonathan and Andrei, Cristina and Rudolph, Matthias}, title = {On the repeatability of low cost varactor—based RF impedance tuners}, series = {2025 55th European Microwave Conference (EuMC)}, journal = {2025 55th European Microwave Conference (EuMC)}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-2-87487-081-1}, doi = {10.23919/EuMC65286.2025.11234977}, pages = {683 -- 686}, abstract = {This paper introduces a concise methodology for assessing the repeatability of low-cost, varactor-based RF impedance tuners by employing a dB-based metric that quantifies how accurately each tuner reproduces a target impedance over repeated cycles. Both blocked and cyclical measurement strategies are used to highlight large impedance transitions near high-reflection states that exacerbate non-idealities. In addition, the method rigorously characterizes issues such as systematic offsets, drift, and hysteresis, common challenges that can impair tuner performance, allowing targeted improvements. Demonstrations with a BST varactor prototype underscore the importance of identifying and quantifying these effects to ensure consistent tuner performance in real-world RF testing environments.}, language = {en} } @incollection{GailingNaumannRudolph, author = {Gailing, Ludger and Naumann, Matthias and Rudolph, David}, title = {Local and regional conflicts in the energy transition}, series = {Reference module in materials science and materials engineering}, booktitle = {Reference module in materials science and materials engineering}, publisher = {Elsevier BV}, address = {Amsterdam}, isbn = {978-0-12-803581-8}, doi = {10.1016/B978-0-443-29210-1.00073-X}, pages = {1 -- 9}, abstract = {Energy transitions are accompanied by a range of conflicts, which mostly occur at local and regional scales. To help understand these, this chapter provides a typology of energy conflicts, of which the most common are distribution and procedural conflicts. Energy conflicts entail material, spatial, temporal and actor dimensions. For both major types of energy conflict and their different dimensions, the chapter provides empirical examples from Denmark and the United Kingdom. Energy conflicts are a challenge for energy transitions, but they are also drivers of social change, which are inherent in the pluralistic structure of modern societies.}, language = {en} }