@article{34232,
abstract = {{In this paper, the theory of phase-locking of a microwave oscillator on the interharmonics, i.e. non-integer harmonics, of the repetition rate of the optical pulse train of a mode-locked laser (MLL) is developed. A balanced optical microwave phase detector (BOMPD) is implemented using a balanced Mach-Zehnder modulator and is employed to discriminate the phase difference between the envelope of the optical pulses and the microwave oscillator. It is shown mathematically that the inherent nonlinear properties of BOMPD with respect to the microwave excitation amplitude can be used for interharmonic locking. The characteristic functions of the phase detector for interharmonic locking are derived analytically and are compared with the measurement results. An opto-electronic phase-locked loop (OEPLL) is demonstrated whose output frequency locks on interharmonics of the MLL repetition rate when an appropriate modulator bias and sufficient RF amplitude are applied. Thus, for the first time theory and experiment of reliable locking on interharmonics of the repetition rate of a MLL are presented.}},
author = {{Bahmanian, Meysam and Kress, Christian and Scheytt, J. Christoph}},
issn = {{1094-4087}},
journal = {{Optics Express}},
number = {{5}},
publisher = {{Optica Publishing Group}},
title = {{{Locking of microwave oscillators on the interharmonics of mode-locked laser signals}}},
doi = {{10.1364/oe.451894}},
volume = {{30}},
year = {{2022}},
}
@inproceedings{34233,
author = {{Singh, Karanveer and Kress, Christian and Mandalawi, Younus and Misra, Arijit and Preussler, Stefan and Scheytt, J. Christoph and Schneider, Thomas}},
booktitle = {{Next-Generation Optical Communication: Components, Sub-Systems, and Systems XI}},
editor = {{Li, Guifang and Nakajima, Kazuhide}},
publisher = {{SPIE}},
title = {{{Analysis of the effect of jitter and non-idealities on photonic digital-to-analog converters based on Nyquist pulses}}},
doi = {{10.1117/12.2609501}},
year = {{2022}},
}
@inproceedings{34234,
author = {{Singh, Karanveer and Meier, Janosch and Kress, Christian and Misra, Arijit and Schwabe, Tobias and Preussler, Stefan and Scheytt, J. Christoph and Schneider, Thomas}},
booktitle = {{Next-Generation Optical Communication: Components, Sub-Systems, and Systems XI}},
editor = {{Li, Guifang and Nakajima, Kazuhide}},
publisher = {{SPIE}},
title = {{{Emulation of integrated high-bandwidth photonic AWG using low-speed electronics}}},
doi = {{10.1117/12.2609416}},
year = {{2022}},
}
@article{34235,
abstract = {{We demonstrate for the first time, to the best of our knowledge, reconfigurable and real-time orthogonal time-domain detection of a high-bandwidth Nyquist signal with a low-bandwidth silicon photonics Mach-Zehnder modulator based receiver. As the Nyquist signal has a rectangular bandwidth, it can be multiplexed in the wavelength domain without any guardband as a part of a Nyquist-WDM superchannel. These superchannels can be additionally multiplexed in space and polarization. Thus, the presented demonstration can open a new possibility for the detection of multidimensional parallel data signals with silicon photonics. No external pulse source is needed for the receiver, and frequency-time coherence is used to sample the incoming Nyquist signal with orthogonal sinc-shaped Nyquist pulse sequences. All parameters are completely tunable in the electrical domain. The feasibility of the scheme is demonstrated through a proof-of-concept experiment over the entire C-band (1530 nm–1560 nm), employing a 24 Gbaud Nyquist QPSK signal due to experimental constraints on the transmitter side electronics. However, the silicon Mach-Zehnder modulator with a 3-dB bandwidth of only 16 GHz can process Nyquist signals of 90 GHz optical bandwidth, suggesting a possibility to detect symbol rates up to 90 GBd in an integrated Nyquist receiver.}},
author = {{Misra, Arijit and Kress, Christian and Singh, Karanveer and Meier, Janosch and Schwabe, Tobias and Preussler, Stefan and Scheytt, J. Christoph and Schneider, Thomas}},
issn = {{1094-4087}},
journal = {{Optics Express}},
number = {{8}},
publisher = {{Optica Publishing Group}},
title = {{{Reconfigurable and real-time high-bandwidth Nyquist signal detection with low-bandwidth in silicon photonics}}},
doi = {{10.1364/oe.454163}},
volume = {{30}},
year = {{2022}},
}
@inproceedings{34236,
abstract = {{We report for the first time, inter-symbol-interference (ISI) free demultiplexing of Nyquist optical time division multiplexed (OTDM) signals using a reconfigurable orthogonal sinc-pulse sampling enabled by silicon photonic Mach-Zehnder Modulators.}},
author = {{Misra, Arijit and Singh, Karanveer and Meier, Janosch and Kress, Christian and Schwabe, Tobias and Preussler, Stefan and Scheytt, J. Christoph and Schneider, Thomas}},
booktitle = {{Conference on Lasers and Electro-Optics}},
publisher = {{Optica Publishing Group}},
title = {{{Flexible Time-Domain De-Multiplexing of Nyquist OTDM Channels by Orthogonal Sampling in Silicon Photonics}}},
doi = {{10.1364/cleo_si.2022.sth5m.2}},
year = {{2022}},
}
@inproceedings{32125,
abstract = {{Fault coverage analysis and fault simulation are well-established methods for the qualification of test vectors in hardware design. However, their role in virtual prototyping and the correlation to later steps in the design process need further investigation. We introduce a metric for RISC-V instruction and register coverage for binary software. The metric measures if RISC-V instruction types are executed and if GPRs, CSRs, and FPRs are accessed. The analysis is applied by the means of a virtual prototype which is based on an abstract instruction and register model with direct correspondence to their bit level representation. In this context, we analyzed three different openly available test suites: the RISC-V architectural testing framework, the RISC-V unit tests, and programs which are automatically generated by the RISC-V Torture test generator. We discuss their tradeoffs and show that by combining them to a unified test suite we can arrive at a 100% GPR and FPR register coverage and a 98.7% instruction type coverage.}},
author = {{Adelt, Peer and Koppelmann, Bastian and Müller, Wolfgang and Scheytt, Christoph}},
booktitle = {{MBMV 2021 - Methods and Description Languages for Modelling and Verification of Circuits and Systems; GMM/ITG/GI-Workshop}},
isbn = {{978-3-8007-5500-4}},
publisher = {{VDE}},
title = {{{Register and Instruction Coverage Analysis for Different RISC-V ISA Modules}}},
year = {{2021}},
}
@inproceedings{32132,
abstract = {{Die Werkzeugdemonstration des QEMU Timing Analyzers (QTA) stellt eine Erweiterung des quelloffenen CPU Emulators QEMU zur Simulation von Softwareprogrammen und deren Worst-Case Zeitverhaltens vor, das durch eine statische Zeitanalyse vorher aus dem Softwareprogramm extrahiert wurde. Der Ablauf der Analyse gliedert sich in mehrere Schritte: Zunächst wird für das zu simulierende Binärprogramm eine WCET-Analyse mit aiT durchgeführt. Im Preprocessing des aiT-Reports wird daraufhin ein WCET-annotierter Kontrollflussgraph erzeugt. Dabei entsprechen die Knoten im Kontrollflussgraph den aiT-Blöcken und die Kanten dem jeweiligen Worst-Case-Zeitverbrauch, um das Programm im aktuellen Ausführungskontext vom Quell- bis zum Zielblock laufen zu lassen. Nach dem Preprocessing werden Binärprogramm und der zuvor erzeugte, zeitannotierte Kontrollflussgraph von QEMU geladen und gemeinsam simuliert.
Die Implementierung des QTA basiert auf der Standard TGI Plugin API (Tiny Code Generator Plugin API), die seit Ende 2019 mit QEMU V4.2 verfügbar ist. Dieses API erlaubt die Entwicklung von versionsunabhängigen QEMU-Erweiterungen. Die QEMU-QTA-Erweiterung wird zum Zeitpunkt der Werkzeugdemonstration inklusive des ait2qta-Preprozessors unter github.com im Quellcode frei verfügbar sein.
Die Demonstration geht von einer existierenden aiT-Analyse eines für TriCore© kompilierten binären Softwareprograms aus, erläutert das Kontrollflusszwischenformat und zeigt die zeitannotierte Simulation der Software.}},
author = {{Adelt, Peer and Koppelmann, Bastian and Müller, Wolfgang and Scheytt, Christoph}},
booktitle = {{MBMV 2021 - Methods and Description Languages for Modelling and Verification of Circuits and Systems; GMM/ITG/GI-Workshop}},
keywords = {{QEMU, aiT, Zeitannotation, WCET}},
publisher = {{VDE}},
title = {{{QEMU zur Simulation von Worst-Case-Ausführungszeiten}}},
year = {{2021}},
}
@article{29210,
abstract = {{This paper investigates an ultra-broadband sampling technique based on charge sampling using an Integrate-and-Hold Circuit (IHC) and ultra-short integration times. The charge sampling technique is mathematically analyzed in detail and compared to conventional switched-capacitor sampling. The mathematical analysis allows to predict the sampler bandwidth as well as the degradation of sampling precision due to analog circuit impairments such as integrator gain error, integration capacitor leakage, hold-mode droop, thermal noise, and clock jitter. Furthermore, design, simulation, and measurement results of an ultra-broadband charge sampler IC in SiGe BiCMOS technology are presented. The charge sampler IC achieves a 1dB bandwidth of 70 GHz. A resolution of better than 5.9 effective number of bits (ENOB) is measured from 0 to 70 GHz at a sampling rate of 5 GS/s. The results suggest that charge sampling using an IHC is a viable concept for ultra-broadband sampling.}},
author = {{Wu, Liang and Scheytt, J. Christoph}},
issn = {{1549-8328}},
journal = {{IEEE Transactions on Circuits and Systems I: Regular Papers}},
keywords = {{Electrical and Electronic Engineering}},
number = {{9}},
pages = {{3668--3681}},
publisher = {{Institute of Electrical and Electronics Engineers (IEEE)}},
title = {{{Analysis and Design of a Charge Sampler With 70-GHz 1-dB Bandwidth in 130-nm SiGe BiCMOS}}},
doi = {{10.1109/tcsi.2021.3094428}},
volume = {{68}},
year = {{2021}},
}
@inproceedings{29217,
abstract = {{The circuit design and measurement results of a mixed-signal receiver baseband circuit for a wireless high data rate communication system are presented. The circuit design of the two most important system blocks of the sliced receiver baseband architecture, namely the broadband, programmable code-generator circuit, and the integrate and dump correlator circuit are explained. Using parallel sequence spread spectrum (PSSS) with PAM-4 modulated data, a net data rate of 2.22 Gbps is demonstrated with a single receiver baseband slice circuit working with a chip rate of 20 Gcps. A total of 15 slices are required to recover all 15 parallelly transmitted symbols resulting in the net data rate of 33.33 Gbps. This is the first reported implementation of a mixed-signal PSSS baseband circuit.}},
author = {{Javed, Abdul Rehman and Scheytt, J. Christoph}},
booktitle = {{2021 IEEE International Midwest Symposium on Circuits and Systems (MWSCAS)}},
publisher = {{IEEE}},
title = {{{Mixed-Signal Receiver Baseband Slice for High-Data-Rate Communication Using 130 nm SiGe BiCMOS Technology}}},
doi = {{10.1109/MWSCAS47672.2021.9531711}},
year = {{2021}},
}
@inproceedings{29221,
abstract = {{An m-sequence radar with a high chip rate of 20 Gcps is presented that makes use of the large bandwidth available in the V-band (40-75 GHz) or at 240 GHz to reduce the detection resolution to 7.5 mm. Measurement results of a mixed-signal radar receiver baseband (BB) integrated circuit designed using 130 nm SiGe BiCMOS technology are presented along with a novel radar ranging concept for the mixed-signal radar BB.}},
author = {{Javed, Abdul Rehman and Scheytt, J. Christoph}},
booktitle = {{2020 17th European Radar Conference (EuRAD)}},
publisher = {{IEEE}},
title = {{{M-Sequence Radar for High Resolution Ranging with Mixed-Signal Radar Receiver Baseband Using 130nm SiGe BiCMOS Technology}}},
doi = {{10.1109/EuRAD48048.2021.00029}},
year = {{2021}},
}
@inproceedings{29213,
abstract = {{This paper presents a technique to extend the frequency acquisition range for bang-bang phase-detector-based clock and data recovery (CDR) circuits without an additional frequency acquisition loop or lock detection circuit. The per-manent modulation of the offset current in the CDR's integral branch enhances the acquisition range by nearly 4 times, covering the entire tuning range of the voltage controlled oscillator. The increase in power dissipation and the chip area are negligible. This technique was implemented and measured in a 28 Gbps NRZ bang-bang CDR chip to confirm the working principle. In addition to the increased acquisition range, the CDR also surpasses jitter related specifications from the OIF CEI-28G-VSR standard.}},
author = {{Iftekhar, Mohammed and Gudyriev, Sergiy and Scheytt, J. Christoph}},
booktitle = {{The 2021 IEEE BiCMOS and Compound Semiconductor Integrated Circuits and Technology Symposium}},
title = {{{Reference-less Bang-bang CDR with Enhanced Frequency Acquisition Range Using Static and Modulated Integral Branch Offset Currents}}},
doi = {{10.1109/BCICTS50416.2021.9682207}},
year = {{2021}},
}
@inproceedings{29215,
abstract = {{We demonstrate a photonic-electronic analog-to-digital converter (ADC) offering a record-high acquisition bandwidth of 320 GHz. The system combines a high-speed electro-optic modulator with a Kerr comb for spectrally sliced coherent detection and is used for digitizing ultra-broadband data signals.}},
author = {{Fang, Dengyang and Drayß, Daniel and Lihachev, Grigory and Marin-Palomo, Pablo and Peng, Hui and Füllner, Christoph and Kuzmin, A and Liu, J and Wang, Ruoyu and Snigirev, Viacheslav and Lukashchuk, Anton and Zang, M and Kharel, P. and Witzens, Jeremy and Scheytt, J. Christoph and Freude, Wolfgang and Randel, Sebastian and Kippenberg, Tobias J. and Koos, Christian}},
booktitle = {{2021 European Conference on Optical Communication (ECOC)}},
publisher = {{IEEE}},
title = {{{320 GHz Analog-to-Digital Converter Exploiting Kerr Soliton Combs and Photonic-Electronic Spectral Stitching}}},
doi = {{10.1109/ECOC52684.2021.9606090}},
year = {{2021}},
}
@inproceedings{23992,
author = {{Adelt, Peer and Koppelmann, Bastian and Müller, Wolfgang and Scheytt, Christoph}},
booktitle = {{Workshop Methoden und Beschreibungssprachen zur Modellierung und Verifikation von Schaltungen und Systemen (MBMV 2021)}},
title = {{{Register and Instruction Coverage Analysis for Different RISC-V ISA Modules}}},
year = {{2021}},
}
@inproceedings{29203,
abstract = {{We present a monolithically integrated electronic-photonic Mach-Zehnder modulator with a linear, segmented driver on the same silicon substrate. As metric for the modulation efficiency, the external V$\pi$ is hereby reduced to only 420 mV.}},
author = {{Kress, Christian and Singh, Karanveer and Schwabe, Tobias and Preußler, Stefan and Schneider, Thomas and Scheytt, J. Christoph}},
booktitle = {{OSA Advanced Photonics Congress 2021}},
keywords = {{Analog to digital converters, Extinction ratios, Grating couplers, Modulation, Modulators, Phase shift}},
pages = {{IW1B.1}},
publisher = {{Optical Society of America}},
title = {{{High Modulation Efficiency Segmented Mach-Zehnder Modulator Monolithically Integrated with Linear Driver in 0.25 \textmum BiCMOS Technology}}},
doi = {{10.1364/IPRSN.2021.IW1B.1}},
year = {{2021}},
}
@article{29204,
abstract = {{An analysis of an optical Nyquist pulse synthesizer using Mach-Zehnder modulators is presented. The analysis allows to predict the upper limit of the effective number of bits of this type of photonic digital-to-analog converter. The analytical solution has been verified by means of electro-optic simulations. With this analysis the limiting factor for certain scenarios: relative intensity noise, distortions by driving the Mach-Zehnder modulator, or the signal generator phase noise can quickly be identified.}},
author = {{Kress, Christian and Bahmanian, Meysam and Schwabe, Tobias and Scheytt, J. Christoph}},
journal = {{Opt. Express}},
keywords = {{Analog to digital converters, Diode lasers, Laser sources, Phase noise, Signal processing, Wavelength division multiplexers}},
number = {{15}},
pages = {{23671–23681}},
publisher = {{OSA}},
title = {{{Analysis of the effects of jitter, relative intensity noise, and nonlinearity on a photonic digital-to-analog converter based on optical Nyquist pulse synthesis}}},
doi = {{10.1364/OE.427424}},
volume = {{29}},
year = {{2021}},
}
@inproceedings{29219,
abstract = {{We demonstrate for the first time, to the best of our knowledge, reconfigurable and real-time orthogonal time-domain demultiplexing of coherent multilevel Nyquist signals in silicon photonics. No external pulse source is needed and frequencytime coherence is used to sample the incoming Nyquist OTDM signal with orthogonal sinc-shaped Nyquist pulse sequences using Mach-Zehnder modulators. All the parameters such as bandwidth and channel selection are completely tunable in the electrical domain. The feasibility of this scheme is demonstrated through a demultiplexing experiment over the entire C-band (1530 nm - 1550 nm), employing 24 Gbaud Nyquist QAM signals due to experimental constraints on the transmitter side. However, the silicon Mach-Zehnder modulator with a 3-dB bandwidth of only 16 GHz can demultiplex Nyquist pulses of 90 GHz optical bandwidth suggesting a possibility to reach symbol rates up to 90 GBd in an integrated Nyquist transceiver. }},
author = {{Misra, Arijit and Singh, Karanveer and Meier, Janosch and Kress, Christian and Schwabe, Tobias and Preussler, Stefan and Scheytt, J. Christoph and Schneider, Thomas}},
booktitle = {{Electrical Engineering and Systems Science}},
title = {{{Reconfigurable and Real-Time Nyquist OTDM Demultiplexing in Silicon Photonics}}},
doi = {{https://doi.org/10.1364/OE.454163}},
year = {{2021}},
}
@article{29209,
abstract = {{We demonstrate an optical arbitrary waveform measurement (OAWM) system that exploits a bank of silicon photonic (SiP) frequency-tunable coupled-resonator optical waveguide (CROW) filters for gapless spectral slicing of broadband optical signals. The spectral slices are coherently detected using a frequency comb as a multi-wavelength local oscillator (LO) and stitched together by digital signal processing (DSP). For high-quality signal reconstruction, we have implemented a maximum-ratio combining (MRC) technique based on precise calibration of the complex-valued opto-electronic transfer functions of all detection paths. In a proof-of-concept experiment, we demonstrate the viability of the scheme by implementing a four-channel system that offers an overall detection bandwidth of 140 GHz. Exploiting a femtosecond laser with precisely known pulse shape for calibration along with dynamic amplitude and phase estimation, we reconstruct 100 GBd QPSK, 16QAM and 64QAM optical data signals. The reconstructed signals show improved quality compared to that obtained with a single high-speed intradyne receiver, while the electronic bandwidth requirements of the individual coherent receivers are greatly reduced.}},
author = {{Fang, Dengyang and Zazzi, Andrea and Müller, Juliana and Dray, Daniel and Fullner, Christoph and Marin-Palomo, Pablo and Tabatabaei Mashayekh, Alireza and Dipta Das, Arka and Weizel, Maxim and Gudyriev, Sergiy and Freude, Wolfgang and Randel, Sebastian and Scheytt, J. Christoph and Witzens, Jeremy and Koos, Christian}},
issn = {{0733-8724}},
journal = {{Journal of Lightwave Technology}},
keywords = {{Atomic and Molecular Physics, and Optics}},
pages = {{1--1}},
publisher = {{Institute of Electrical and Electronics Engineers (IEEE)}},
title = {{{Optical Arbitrary Waveform Measurement Using Silicon Photonic Slicing Filters}}},
doi = {{10.1109/jlt.2021.3130764}},
year = {{2021}},
}
@article{29211,
abstract = {{Electrical-optical signal processing has been shown to be a promising path to overcome the limitations of state-of-the-art all-electrical data converters. In addition to ultra-broadband signal processing, it allows leveraging ultra-low jitter mode-locked lasers and thus increasing the aperture jitter limited effective number of bits at high analog signal frequencies. In this paper, we review our recent progress towards optically enabled time- and frequency-interleaved analog-to-digital converters, as well as their monolithic integration in electronic-photonic integrated circuits. For signal frequencies up to 65 GHz, an optoelectronic track-and-hold amplifier based on the source-emitter-follower architecture is shown as a power efficient approach in optically enabled BiCMOS technology. At higher signal frequencies, integrated photonic filters enable signal slicing in the frequency domain and further scaling of the conversion bandwidth, with the reconstruction of a 140 GHz optical signal being shown. We further show how such optically enabled data converter architectures can be applied to a nonlinear Fourier transform based integrated transceiver in particular and discuss their applicability to broadband optical links in general.}},
author = {{Zazzi, Andrea and Müller, Juliana and Weizel, Maxim and Koch, Jonas and Fang, Dengyang and Moscoso-Martir, Alvaro and Tabatabaei Mashayekh, Ali and Das, Arka D. and Drays, Daniel and Merget, Florian and Kartner, Franz X. and Pachnicke, Stephan and Koos, Christian and Scheytt, J. Christoph and Witzens, Jeremy}},
issn = {{2644-1349}},
journal = {{IEEE Open Journal of the Solid-State Circuits Society}},
pages = {{209--221}},
publisher = {{Institute of Electrical and Electronics Engineers (IEEE)}},
title = {{{Optically Enabled ADCs and Application to Optical Communications}}},
doi = {{10.1109/ojsscs.2021.3110943}},
volume = {{1}},
year = {{2021}},
}
@article{29212,
author = {{Fang, Dengyang and Zazzi, Andrea and Müller, Juliana and Daniel, Drayß and Füllner, Christoph and Marin-Palomo, Pablo and Mashayekh, Ali Tabatabaei and Das, Arka Dipta and Weizel, Maxim and Gudyriev, Sergiy and Freude, Wolfgang and Randel, Sebastian and Scheytt, J. Christoph and Witzens, Jeremy and Koos, Christian}},
isbn = {{978-1-943580-86-6}},
journal = {{OSA Technical Digest}},
title = {{{Optical Arbitrary Waveform Measurement (OAWM) on the Silicon Photonic Platform}}},
doi = {{10.1109/JLT.2021.3130764}},
year = {{2021}},
}
@article{23476,
author = {{Weizel, Maxim and Scheytt, J. Christoph and Kärtner, Franz X. and Witzens, Jeremy}},
issn = {{1094-4087}},
journal = {{Optics Express}},
title = {{{Optically clocked switched-emitter-follower THA in a photonic SiGe BiCMOS technology}}},
doi = {{10.1364/oe.425710}},
year = {{2021}},
}