Recent publications

February 2023

MIMO Systems with Reconfigurable Antennas: Joint Channel Estimation and Mode Selection

Fariba Armandoust, Ehsan Tohidi, Martin Kasparick, Li Wang, Ahmet Hasim Gokceoglu, Slawomir Stanczak

In this paper, we develop a low-complexity iterative mode selection algorithm for data transmission in a Reconfigurable antennas (RAs) MIMO system. Furthermore, we study channel estimation of an RA multi-user MIMO system. We propose a mode...


January 2023

Quantus: An Explainable AI Toolkit for Responsible Evaluation of Neural Network Explanations and Beyond

Anna Hedström, Wojciech Samek, Sebastian Lapuschkin, Leander Weber, Dilyara Bareeva, Franz Motzkus, Marina M.-C. Höhne, Daniel Krakowczyk

Explainability is supposed to strengthen trust in artificial intelligence, it is necessary to systematically review and compare explanation methods in order to confirm their correctness. We therefore built Quantus—a comprehensive, evaluation...


January 2023

Enabling Optical Modulation Format Identification Using an Integrated Photonic Reservoir and a Digital Multiclass Classifier

Guillermo von Hünefeld, Colja Schubert, Ronald Freund, Isaac Sackey, Gregor Ronniger, Johannes K. Fischer, Pooyan Safari, Rijil Thomas, Enes Seker, Piotr Cegielski, Stephan Suckow, Max Lemme, David Stahl, Sarah Masaad, Emmanuel Gooskens, Peter Bienstman

We numerically show modulation format identification in the optical domain using Silicon-on-Insulator-based Photonic-Integrated-Circuit (PIC) reservoir. Identification of 32 GBd single-polarization signals of OOK, PAM4, BPSK and QPSK is...


January 2023

Ultrafast quantum key distribution using fully parallelized quantum channels

Robin Terhaar, Nicolas Perlot, Jasper Rödiger, Fabian Beutel, M. Wolff, Jonas Hanke, Nino Walenta, W. Hartmann, M. Häußler, M. Wahl, T. Röhlicke, W. H. P. Pernice, C. Schuck, Helge Gehring, Nicolai Walter, Peter Hanne, Maximilian Diedrich, Max Tillmann, Mahdi Ahangarianabhari

Quantum key distribution (QKD) offers secure communication protected by the laws of quantum mechanics. Aiming for an application-oriented solution, we designed a multichannel superconducting nanowire single photon detector system, as well as a...


January 2023

Recovering Fine Details for Neural Implicit Surface Reconstruction

Decai Chen, Oliver Schreer, Peter Eisert, Ingo Feldmann, Peng Zhang

In this paper, we present D-NeuS, a volume rendering-based neural implicit surface reconstruction method capable to recover fine geometry details, which extends NeuS by two additional loss functions targeting enhanced reconstruction quality.


January 2023

Continuous intraoperative perfusion monitoring of free microvascular anastomosed fasciocutaneous flaps using remote photoplethysmography

Sebastian Schraven, Peter Eisert, Anna Hilsmann, Eric Wisotzky, Benjamin Kossack, Maximilian Jung, Lotte Skopnik, Robert Mlynski, Daniel Strüder, Justus Groß

Intraoperative monitoring of free flaps using remote photoplethysmography (rPPG) signal provides objective and reproducible data on tissue perfusion. We developed a monitoring algorithm for flap perfusion, which was evaluated in fifteen patients...


January 2023

Investigating the Performance and Suitability of Neural Network Architectures for Nonlinearity Mitigation of Optical Signals

Vegenshanti Valerian Dsilva, Colja Schubert, Ronald Freund, Isaac Sackey, Gregor Ronniger, Guillermo von Hünefeld, Binoy Chacko

We compare three different neural network architectures for nonlinearity mitigation of 32 GBd OOK and QPSK signals after transmission over a dispersion-compensated link of 10-km SSMF and 10-km DCF. OSNR gains up to 2.2 dB were achieved using...


January 2023

Experimental Study of In-line Nonlinearity Mitigation for a 400 Gb/s Dual-Carrier Superchannel with Joint Reception Using a Waveband-Shift-Free OPC

Isaac Sackey, Colja Schubert, Carsten Schmidt-Langhorst, Ronald Freund, Robert Elschner, Tomoyuki Kato, Takeshi Hoshida, Gregor Ronniger

We experimentally study waveband-shift-free optical phase conjugation (OPC) of a 400-Gb/s dual-carrier superchannel and discuss the effectiveness of the OPC for multi-channel nonlinear mitigation. After joint reception of the 31.44 GBd-PDM-16QAM...


January 2023

Ultra-Wideband All-optical Interband Wavelength Conversion Using a Low-complexity Dispersion-engineered SOI Waveguide

Isaac Sackey, Colja Schubert, Carsten Schmidt-Langhorst, Ronald Freund, Robert Elschner, Tomoyuki Kato, Takeshi Hoshida, Gregor Ronniger, Hidenobu Muranaka, Shun Okada, Yu Tanaka, Tsuyoshi Yamamoto, Md Mahasin KhanIsaac Sackey, Colja Schubert, Carsten Schmidt-Langhorst, Ronald Freund, Robert Elschner, Tomoyuki Kato, Takeshi Hoshida, Gregor Ronniger, Hidenobu Muranaka, Shun Okada, Yu Tanaka, Tsuyoshi Yamamoto, Md Mahasin Khan

We experimentally present a low-complexity dispersion-engineered all-optical wavelength-converter using a photonic integrated-circuit based on SOI waveguide. We achieve a single-sided conversion bandwidth of ~35 nm from C- to S-band, and...


December 2022

Increasing the reach of visible light communication links through constant-envelope OFDM signals

Higor Camporez, Volker Jungnickel, Ronald Freund, Anagnostis Paraskevopoulos, Malte Hinrichs, Wesley Da Silva Costa, Maria Pontes, Marcelo Segatto, Helder Rocha, Jair Silva

We demonstrate the transmission of constant-envelope orthogonal frequency division multiplexing (CE-OFDM) signals, based on electrical phase modulation, in a visible light communication (VLC) system. An increased tolerance to nonlinearity...



Items per page10ǀ20ǀ30
Results 91-100 of 263
<< < 7 8 9 10 11 12 13 14 > >>