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A multiport vector network analyzer with high-precision and realtime capabilities for brain imaging and stroke detection
Sebastian Poltschak, Markus Freilinger, Reinhard Feger, Andreas Stelzer, Abouzar Hamidipour, Tommy Henriksson, Markus Hopfer, Ramon Planas, Serguei Semenov
Medical imaging is of great importance for patients affected by stroke. Since an early examination of the patient is necessary for successful recovery, there is room to improve the existing capabilities of analysis. Common systems like magnetic resonance imaging or computed tomography are precise, but stationary, and therefore, not ideally suited for the early analysis of stroke. The presented mul
Multi-functional D-band / modulator/demodulator MMICs in SiGe BiCMOS technology
Sona Carpenter, Zhongxia Simon He, Herbert Zirath
This paper presents the design and characterization of a D-band (110?170 GHz) monolithic microwave integrated direct carrier quadrature modulator and demodulator circuits with on-chip quadrature local oscillator (LO) phase shifter and radio frequency (RF) balun fabricated in a 130 nm SiGe BiCMOS process with / of 250 GHz/400 GHz. These circuits are suitable for low-power ultra-high-speed wireless
A 219?266 GHz LO-tunable direct-conversion IQ receiver module in a SiGe HBT technology
P. Rodriguez Vazquez, J. Grzyb, N. Sarmah, B. Heinemann, U.R. Pfeiffer
This paper presents a fully-integrated direct-conversion fundamentally-operated mixer-first quadrature receiver module with a tunable LO in the 219?266 GHz band. It has been implemented in a 0.13-?m SiGe heterojunction bipolar transistor technology. It includes an on-chip LO path driven externally from the printed circuit board (PCB) connector level at 13.6?16.7 GHz. A hybrid coupler generates the
Automotive antenna diversity system for satellite radio with high phase accuracy in low SNR-scenarios
Simon Senega, Ali Nassar, Stefan Lindenmeier
For a fast scan-phase satellite radio antenna diversity system a noise correction method is presented for a significant improvement of audio availability at low signal-to-noise ratio (SNR) conditions. An error analysis of the level and phase detection within the diversity system in the presence of noise leads to a correction method based on a priori knowledge of the system's noise floor. This meth
Analysis of multipath and DOA detection using a fully polarimetric automotive radar
Tristan Visentin, Jürgen Hasch, Thomas Zwick
Multipath propagation occurs in many situations of radar measurements in complex environments. The unwanted effects range from interference over the radar channels, which causes amplitude fading and a corrupted direction of arrival (DOA) estimation, to the detection of ghost targets in an angle of arrival of the multipath direction. Due to the different number of reflections, polarimetric radars a
A 216?256 GHz fully differential frequency multiplier-by-8 chain with 0 dBm output power
M.H. Eissa, A. Malignaggi, M. Ko, K. Schmalz, J. Borngräber, A.C. Ulusoy, D. Kissinger
This work presents a fully differential wideband and low power 240 GHz multiplier-by-8 chain, manufactured in IHP's 130 nm SiGe:C BiCMOS technology with / = 300/500 GHz. A single ended 30 GHz input signal is multiplied by 8 using Gilbert cell-based quadrupler and doubler, and then amplified with a wideband differential 3-stage cascode amplifier. To achieve wide bandwidth and optimize for power con
Scanning microwave microscopy of buried CMOS interconnect lines with nanometer resolution
Xin Jin, Kuanchen Xiong, Roderick Marstell, Nicholas C. Strandwitz, James C. M. Hwang, Marco Farina, Alexander Göritz, Matthias Wietstruck, Mehmet Kaynak
This paper reports scanning microwave microscopy of CMOS interconnect aluminum lines both bare and buried under oxide. In both cases, a spatial resolution of 190 ± 70 nm was achieved, which was comparable or better than what had been reported in the literature. With the lines immersed in water to simulate high- dielectric, the signal-to-noise ratio degraded significantly, but the image remained as
KIT coaxial gyrotron development: from ITER toward DEMO
S. Ruess, K. A. Avramidis, M. Fuchs, G. Gantenbein, Z. Ioannidis, S. Illy, J. Jin, P. C. Kalaria, T. Kobarg, I. Gr. Pagonakis, T. Ruess, T. Rzesnicki, M. Schmid, M. Thumm, J. Weggen, A. Zein, J. Jelonnek
Karlsruhe Institute of Technology (KIT) is doing research and development in the field of megawatt-class radio frequency (RF) sources (gyrotrons) for the Electron Cyclotron Resonance Heating (ECRH) systems of the International Thermonuclear Experimental Reactor (ITER) and the DEMOnstration Fusion Power Plant that will follow ITER. In the focus is the development and verification of the European co
Radiometric accuracy and stability of sentinel-1A determined using point targets
Kersten Schmidt, Núria Tous Ramon, Marco Schwerdt
Sentinel-1A is a space-borne synthetic aperture radar (SAR) system developed in the frame of the Copernicus Program. The German Aerospace Center supported the radiometric and polarimetric calibration of Sentinel-1A by the analysis of point target responses of several acquisitions considering different modes, beams, and polarization channels. An elevation dependent bias, which had not been properly
Slow-wave coplanar waveguides based on inductive and capacitive loading and application to compact and harmonic suppressed power splitters
Francisco Aznar-Ballesta, Jordi Selga, Paris Vélez, Armando Fernández-Prieto, Jan Coromina, Jordi Bonache, Ferran Martín
In this paper, a slow-wave transmission line implemented in coplanar waveguide technology, based on simultaneous inductive and capacitive loading, is presented for the first time. The shunt capacitors are achieved by periodically etching transverse strips in the back substrate side, connected to the central strip through metallic vias. The series inductors are implemented by etching rectangular sl
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