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System architecture for a compact high range resolution frequency comb OFDM radar
Alexander Quint, Benjamin Nuss, Axel Diewald, Thomas Zwick
With increasing demands on resolution and flexibility in current and future radar applications, the focus is moving to digital radar systems such as orthogonal frequency-division multiplexing (OFDM) radars. To achieve high bandwidths and consequently a high range resolution, high sampling rates are needed. To overcome this constraint, an approach called frequency comb OFDM radar has been developed
Plasma state supervision utilizing millimeter wave radar systems
Francesca Schenkel, Christoph Baer, Ilona Rolfes, Christian Schulz
This work introduces a method for plasma state supervision, based on a frequency-modulated continuous wave radar sensor and a suitable signal evaluation enabling a continuous supervision method for the plasma state. Highly precise phase evaluation of the signal allows us to detect and visualize smallest changes in the plasma state. Assuming the plasma to act like a frequency-dependent dielectric m
RF linearity trade-offs for varying T-gate geometries of GaN HEMTs on Si
Rana ElKashlan, Ahmad Khaled, Raul Rodriguez, Arturo Sibaja-Hernandez, Uthayasankaran Peralagu, AliReza Alian, Nadine Collaert, Piet Wambacq, Bertrand Parvais
Short-channel Gallium Nitride (GaN) high-electron-mobility transistors (HEMTs) often utilize T-shape gates due to their large gate-line cross-sectional area and subsequent increase. In this paper, we report the linearity trade-offs associated with varying the T-gate geometries of AlGaN/GaN HEMTs on Si, specifically the gate extensions which serve as field plates and their impact on the large-sign
RCS prediction and optimization for anomalous reflection metasurfaces using Floquet analysis
Matthieu Elineau, Renaud Loison, Stéphane Méric, Raphaël Gillard, Pascal Pagani, Geneviève Mazé-Merceur, Philippe Pouliguen
Due to their periodic nature, metasurfaces used to perform anomalous reflection raise parasitic harmonic reflections. We show a classical synthesis example of such a structure and highlight its limitations. Floquet analysis and its associated simulation environment are exploited to understand the origin of these parasitic reflections and to mitigate them. The proposed method is based on the optimi
A phase-locked loop with a jitter of 50 fs for astronomy applications
Tobias T. Braun, Marcel van Delden, Christian Bredendiek, Jan Schoepfel, Stephan Hauptmeier, William Shillue, Thomas Musch, Nils Pohl
Radio telescopes are among the applications with the highest demands on a local oscillator (LO), which is used to receive and process the signals coming from the sky. Therefore the modules providing the required LO signal have traditionally been big and complicated. To overcome this disadvantage, we implement our own integrated frequency synthesizer inside a small LO module in this article. With t
Metamaterial lenses for monostatic and bistatic 77 GHz radar systems
Christoph Kohlberger, Richard Hüttner, Christoph Wagner, Andreas Stelzer
Metamaterial lenses are appealing thin alternatives to conventional dielectric lenses. In this contribution we describe their design and application in two exemplary 77 GHz automotive radar sensors operating in monostatic and bistatic modes. The frontends are built around commercially available MMICs and small feed antennas are used in coordination with the six-layer printed circuit board-based re
Circuits for 5G RF front-end modules
Florinel Balteanu
Worldwide adoption of fourth-generation wireless (4G) long-term evolution (LTE) smartphones and the actual transition to fifth-generation wireless(5G) is the main driving engine for semiconductor industry. 5G is expected to reach high data rate speeds (1 Gbps) and low latency (<1 ms). 5G requires more RF bandwidth and therefore an increase in the number of components such as RF switches, acoustic
Terahertz non-destructive testing of power generator bars with a dielectric waveguide antenna
Maris Bauer, Raphael Hussung, Carsten Matheis, Andrey Mashkin, Stefan Krane, Friedhelm Pohlmann, Fabian Friederich
Terahertz technologies for non-destructive testing (NDT) are continuing to find their way into the industrial sector in the context of very specific inspection tasks. Part of this development is the capability to adapt terahertz systems in such a way that they can meet the sometimes harsh challenges and requirements of real-world industrial scenarios. One such scenario is the inspection of compone
Miniaturization of folded circular SIW cavity filters
Anton Sieganschin, Bartosz Tegowski, Alexander Koelpin, Arne F. Jacob
This contribution presents miniaturization techniques for folded circular substrate integrated waveguide (FCSIW) cavity filters. The cavities support dual-mode operation. Two of these cavities are combined to form a fourth-order filter. Two filter designs are implemented. The first one serves as a reference and exhibits good manufacturability. For the second one, the cavity is modified, which lead
28 GHz over-the-air measurement using an OTFS multi-user distributed MIMO under Doppler effect
Noriaki Tawa, Toshihide Kuwabara, Yasushi Maruta, Tomoya Kaneko
This paper describes the experimental investigation of orthogonal time-frequency space (OTFS) modulation using a 28 GHz multi-user distributed multiple-input multiple-output (D-MIMO) testbed in over-the-air (OTA) and mobility environments to enhance cell throughput in a millimeter-wave band. We build the D-MIMO testbed having newly developed OTFS modulator and demodulator, and measured OTFS signal
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