Accès ouvert
2026
article
OpenAlex
Alexander Marek, Katharina Mayer, Hannes Kistner, Daniel Leinz et autres
Abstract The gyrotropic and magneto-optical properties of a commercially available $$SrFe_{12}O_{19}$$ S r F e 12 O 19 hard ferrite material are investigated for the first time in the Ka-band (26.5−40 GHz), at frequencies well below the intrinsic ferromagnetic resonance of the …
de, gb
(code pays fourni par la source)
2026
conference-paper
OpenAlex
Alexander Marek, Max Vöhringer, John Jelonnek, Jens Klare et autres
The helical-type gyro-TWT has demonstrated excellent high-power and broadband operation at frequencies up to the W-band, and is also a promising candidate for future applications in the sub-THz frequency range. Recently, an extension of the helical-type gyro-TWT has been proposed, the frequency-doubling …
de
(code pays fourni par la source)
2026
conference-paper
OpenAlex
Katharina Mayer, Alexander Marek, Daniel Leinz, Jens Klare et autres
As the number of space objects increases and their sizes decrease, there is a growing need for improved spatial resolution and sensitivity in radar systems for Space Situational Awareness (SSA) to protect critical space infrastructure. Higher power levels are required to enhance …
de
(code pays fourni par la source)
Accès ouvert
2026
other
OpenAlex
Alexander Marek, Katharina Mayer, Hannes Kistner, Daniel Leinz et autres
The gyrotropic and magneto-optical properties of a commercially available SrFe12O19 hard ferrite material are investigated for the first time in the Ka-band (26.5-40 GHz), at frequencies well below the intrinsic ferromagnetic resonance of the material. Using a vector network analyzer and quasi-optical …
Accès ouvert
2025
other
OpenAlex
Max Vöhringer, Alexander Marek, Stefan Illy, Benjamin Ell et autres
Gyro-traveling-wave amplifiers (TWAs) with a helically corrugated interaction region (HCIR) are used for broadband, high-power amplification of microwave signals. In this publication, an HCIR for 265 GHz (G-band) and the influence of manufacturing tolerances on the HCIR performance are presented. This is …
Accès ouvert
2025
article
OpenAlex
Max Vöhringer, Alexander Marek, S. Illy, Benjamin Ell et autres
Gyro-traveling-wave amplifiers (TWAs) with a helically corrugated interaction region (HCIR) are used for broadband, high-power amplification of microwave signals. In this publication, an HCIR for 265 GHz (G-band) and the influence of manufacturing tolerances on the HCIR performance are presented. This is …
de
(code pays fourni par la source)
2025
conference-paper
OpenAlex
S. Illy, Konstantinos A. Avramidis, Ioannis G. Chelis, Benjamin Ell et autres
In the frame of a EUROfusion Enabling Research (ENR) Project, KIT and NKUA have been working on new technical concepts for highly efficient, megawatt-class fusion gyrotron systems that will operate at the 2nd-harmonic of the electron cyclotron frequency. This will reduce the …
de, gr
(code pays fourni par la source)
2025
conference-paper
OpenAlex
Max Vöhringer, Alexander Marek, S. Illy, Manfred K. A. Thumm et autres
For the operation of a helical-waveguide gyro-TWT a circularly polarized microwave, which is co-rotating with respect to the beam electrons, is required in the interaction region. Hence, the linearly polarized input wave has to be converted into a circularly polarized one. A …
de
(code pays fourni par la source)
2025
conference-paper
OpenAlex
Alexander Marek, Robert Perkuhn, Jens Klare, John Jelonnek et autres
Radar plays a crucial role in the increasingly important field of space situational awareness, essential for the protection of critical space infrastructure. This is achieved through radars for space observation such as the Tracking and Imaging Radar (TIRA) located near Bonn, Germany, …
de
(code pays fourni par la source)
2025
conference-paper
OpenAlex
Max Vöhringer, Alexander Marek, S. Illy, Manfred K. A. Thumm et autres
Gyro-TWTs with helically corrugated interaction region (HCIR) have shown to be effective for broadband and high-power amplification of signals up to the W-band. In this publication, versions for 263 GHz (G-band) are proposed, which are able to generate above 1 kW of …
de
(code pays fourni par la source)
Accès ouvert
2024
article
OpenAlex
Jens Klare, Florian Behner, Claudio Carloni, Delphine Cerutti‐Maori et autres
The use of near-Earth space has grown dramatically during the last decades, resulting in thousands of active and inactive satellites and a huge amount of space debris. To observe and monitor the near-Earth space environment, radar systems play a major role as …
de
(code pays fourni par la source)
2023
conference-paper
OpenAlex
T. Rzesnicki, Konstantinos A. Avramidis, Ioannis G. Chelis, G. Gantenbein et autres
The short-pulse (SP) prototype tube has been initially manufactured at KIT in 2015 to support the development of the European 1 MW, 170 GHz, CW gyrotron for ITER [1]. The SP gyrotron is in operation and used for testing and experimental validation …
de, gr
(code pays fourni par la source)