Prof. Ralf Reulke Profile

Prof. Ralf Reulke

Head of Computer Vision Dept at Humboldt-Universität zu Berlin

SPIE Involvement:

Author

Publications (25)

Proceedings Article | 30 September 2022 Presentation + Paper

In-orbit real-time CMOS TDI detector validation and control to meet constant imaging quality over the mission life time

Johannes Buschek, Kristian Manthey, Andreas Eckardt, Ralf Reulke, Gerhard Kahmen

Proceedings Volume 12232, 1223205 (2022) https://doi.org/10.1117/12.2631978

KEYWORDS: Sensors, Image quality, Signal detection, Signal to noise ratio, Modulation transfer functions, Point spread functions, Image sensors, Charge-coupled devices

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Proceedings Article | 3 October 2019 Presentation + Paper

Analysis of the gas flare flame with IR cameras

Agnieszka Soszynska, Thomas Säuberlich, Christian Fischer, Jörg Borch, Frank Otremba, Ralf Reulke

Proceedings Volume 11156, 1115606 (2019) https://doi.org/10.1117/12.2532887

KEYWORDS: Cameras, Satellites, Sensors, Combustion, Satellite imaging, Point spread functions, Infrared cameras, Remote sensing, Thermal remote sensing

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Proceedings Article | 9 September 2019 Presentation + Paper

Status of the next generation CMOS-TDI detector for high-resolution imaging

Andreas Eckardt, Stefan Glaesener, Ralf Reulke, Karsten Sengebusch, Bernd Zender

Proceedings Volume 11127, 111270J (2019) https://doi.org/10.1117/12.2528698

KEYWORDS: Sensors, Analog electronics, Charge-coupled devices, CMOS sensors, Image sensors, Imaging systems, Field programmable gate arrays, Detector development

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Proceedings Article | 25 September 2018 Presentation + Paper

DESIS - DLR earth sensing imaging spectrometer for the International Space Station ISS

David Krutz, Ilse Sebastian, Andreas Eckardt, Holger Venus, Ingo Walter, Burghardt Günther, Thomas Säuberlich, Michael Neidhardt, Bernd Zender, Matthias Lieder, Rupert Müller, Thomas Peschel, Sandra Müller, Simone Arloth, Ute Grote, Andreas Wojtkowiak, Friedrich Schrandt, Christian Fischer, Agnieszka Soszyńska, Emiliano Carmona, Ralf Reulke

Proceedings Volume 10785, 107850K (2018) https://doi.org/10.1117/12.2325644

KEYWORDS: Sensors, Calibration, Light emitting diodes, Camera shutters, Signal detection, Global Positioning System, Interference (communication), Temperature metrology, Spectroscopy, Space operations

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Proceedings Article | 18 September 2018 Presentation + Paper

Verification and calibration of the DESIS detector

Andreas Eckardt, David Krutz, Thomas Säuberlich, Holger Venus, Ralf Reulke

Proceedings Volume 10768, 107680B (2018) https://doi.org/10.1117/12.2319303

KEYWORDS: Sensors, Quantum efficiency, Calibration, Signal detection, Photons, Signal to noise ratio, Sensor performance, Electroluminescence, Spectroscopy, CMOS sensors

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Proceedings Article | 18 September 2018 Paper

Low cost hyperspectral systems for atmospheric and surface studies

Andreas Eckardt, Ralf Reulke

Proceedings Volume 10768, 107680M (2018) https://doi.org/10.1117/12.2319319

KEYWORDS: Sensors, Cameras, Imaging systems, Hyperspectral imaging, Spectrometers, Fourier transforms, Optical filters, Tunable filters, Hyperspectral systems, Spectral resolution

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Proceedings Article | 9 May 2018 Presentation + Paper

On-ground calibration of DESIS: DLR's Earth Sensing Imaging Spectrometer for the International Space Station (ISS)

Ilse Sebastian, David Krutz, Andreas Eckardt, Holger Venus, Ingo Walter, Burghardt Günther, Michael Neidhardt, Ralf Reulke, Rupert Müller, Mathias Uhlig, Sandra Müller, Thomas Peschel, Simone Arloth, Matthias Lieder, Friedrich Schrandt

Proceedings Volume 10680, 1068002 (2018) https://doi.org/10.1117/12.2307188

KEYWORDS: Calibration, Modulation transfer functions, Sensors, Light emitting diodes, Staring arrays, Spectral calibration, Monochromators, Signal to noise ratio, Camera shutters, Spectroscopy

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Proceedings Article | 5 September 2017 Presentation + Paper

Verification of the Sentinel-4 focal plane subsystem

Christian Williges, Mathias Uhlig, Stefan Hilbert, Hannes Rossmann, Kevin Buchwinkler, Steffen Babben, Ilse Sebastian, Rüdiger Hohn, Ralf Reulke

Proceedings Volume 10402, 104021A (2017) https://doi.org/10.1117/12.2274407

KEYWORDS: Sensors, Modulation transfer functions, Cameras, Imaging systems, Atmospheric modeling, Aerospace engineering, Defense and security, Near infrared, Integrating spheres, Light sources

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Proceedings Article | 5 September 2017 Presentation + Paper

Realization of the electrical Sentinel 4 detector integration

M. Hermsen, R. Hohn, M. Skegg, C. Woffinden, R. Reulke

Proceedings Volume 10402, 1040219 (2017) https://doi.org/10.1117/12.2274392

KEYWORDS: Sensors, Signal detection, CCD image sensors, Charge-coupled devices, Satellites, Electronics, Satellite communications, System integration, Imaging systems, Analog electronics

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The detectors of the Sentinel 4 multi spectral imager are operated in flight at 215K while the analog electronics is operated at ambient temperature. The detector is cooled by means of a radiator. For thermal reasons no active component has been allowed in the cooled area closest to the detector as the passive radiator is restricted in its size. For thermal decoupling of detector and electronics a long distance between detector and electronics is considered ideal as thermal conductivity decreases with the length of the connection. In contradiction a short connection between detector and electronics is ideal for the electronic signals. Only a short connection ensures the signal integrity of both the weak detector output signal but similarly also the clock signals for driving the detector. From a mechanical and thermal point of view the connection requires a certain minimum length. The selected solution serves all these needs but had to approach the limits of what is electrically, mechanically and thermally feasible. In addition, shielding from internal (self distortion) and external distorting signals has to be realized for the connection between FEE(Front End Electronics) and detectors. At the time of the design of the flex it was not defined whether the mechanical structure between FEE and FPA (Focal Plane Assembly) would act as a shielding structure. The physical separation between CCD detector and the Front-end Electronics, the adverse EMI environment in which the instrument will be operated in (the location of the instrument on the satellite is in vicinity to a down-link K-band communication antenna of the S/C) require at least the video output signals to be shielded. Both detectors (a NIR and a UVVIS detector) are sensitive to contamination and difficult to be cleaned in case of any contamination. This brings up extreme cleanliness requirements for the detector in manufacturing and assembly. Effectively the detector has to be kept in an ISO 5 environment and additionally humidity has to be avoided - which does not comply with the usual clean-room atmosphere. This paper describes how in Sentinel 4 the given challenges have been overcome, how the limited load drive capability of the detector component has been considered on a flex length of about 20 cm (7.87 in) and how EMC shielding of the highly sensitive analog signals of the detector has been realized. Also covered are design/manufacturing aspects and a glance on testing results is provided

Proceedings Article | 5 September 2017 Presentation + Paper

The Sentinel-4 detectors: architecture and performance

Michael Skegg, Markus Hermsen, Rüdiger Hohn, Christian Williges, Charles Woffinden, Yves Levillain, Ralf Reulke

Proceedings Volume 10402, 1040218 (2017) https://doi.org/10.1117/12.2274362

KEYWORDS: Sensors, Charge-coupled devices, CCD image sensors, Sensor performance, Atmospheric particles, Calibration, Spectroscopy, Gases, Ozone, NOx

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Proceedings Article | 5 September 2017 Presentation + Paper

RTS effect detection in Sentinel-4 data

Henrique Candeias, Xavier Gnata, Maximilian Harlander, Markus Hermsen, Rüdiger Hohn, Stefan Riedl, Michael Skegg, Christian Williges, Ralf Reulke

Proceedings Volume 10402, 104021B (2017) https://doi.org/10.1117/12.2274310

KEYWORDS: Sensors, Ultraviolet radiation, Charge-coupled devices, CCD image sensors, Signal detection, Spectroscopy, Near infrared, Detector development, Data acquisition, Data modeling

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Proceedings Article | 5 September 2017 Presentation + Paper

The S4 focal plane subsystem

Rüdiger Hohn, Michael Skegg, Markus Hermsen, Jürgen Hinger, Christian Williges, Ralf Reulke

Proceedings Volume 10402, 1040216 (2017) https://doi.org/10.1117/12.2273203

KEYWORDS: Atmospheric monitoring, Algorithm development, Spectroscopy, Atmospheric particles, Ozone, NOx, Sulfur, Aerosols, Clouds, Image segmentation

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Proceedings Article | 24 August 2017 Presentation + Paper

Adaptation of spatial resolution for high resolution imaging system

Andreas Eckardt, Christian Williges, Ralf Reulke

Proceedings Volume 10395, 1039503 (2017) https://doi.org/10.1117/12.2273206

KEYWORDS: Image resolution, Spatial resolution, Imaging systems, Image processing, Cameras, Optical filters, Image filtering, Satellites

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Proceedings Article | 13 October 2014 Paper

Image quality of optical remote sensing data

Ralf Reulke, Thomas Säuberlich

Proceedings Volume 9250, 92500L (2014) https://doi.org/10.1117/12.2068538

KEYWORDS: Image quality, Signal to noise ratio, Point spread functions, Modulation transfer functions, Remote sensing, Sensors, Imaging systems, Image quality standards, Calibration, Image compression

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Proceedings Article | 7 October 2014 Paper

CMOS-TDI detector technology for reconnaissance application

Andreas Eckardt, Ralf Reulke, Melanie Jung, Karsten Sengebusch

Proceedings Volume 9249, 92490X (2014) https://doi.org/10.1117/12.2066464

KEYWORDS: Avalanche photodetectors, Electroluminescent displays, Sensors, Doping, Indium gallium arsenide, Short wave infrared radiation, Infrared radiation, PIN photodiodes, Staring arrays, Absorption

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Proceedings Article | 23 September 2013 Paper

sCMOS detector for imaging VNIR spectrometry

Andreas Eckardt, Ralf Reulke, Horst Schwarzer, Holger Venus, Christian Neumann

Proceedings Volume 8870, 88700G (2013) https://doi.org/10.1117/12.2021361

KEYWORDS: Sensors, Signal to noise ratio, Modulation transfer functions, Quantum efficiency, Aerospace engineering, Cameras, Staring arrays, Camera shutters, Interference (communication), Image sensors

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Proceedings Article | 20 August 2008 Paper

Space instrument performance traceability for high resolution satellite systems

A. Eckardt, A. Börner, H. Jahn, R. Reulke

Proceedings Volume 7081, 70810U (2008) https://doi.org/10.1117/12.792555

KEYWORDS: Modulation transfer functions, Sensors, Space telescopes, Semiconducting wafers, Imaging systems, Telescopes, Sensor performance, Aerospace engineering, Satellites, Detector development

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Proceedings Article | 14 January 2002 Paper

Hardware concept of the first commercial airborne digital sensor

Andreas Eckardt, Ralf Reulke

Proceedings Volume 4488, (2002) https://doi.org/10.1117/12.452806

KEYWORDS: Sensors, Charge-coupled devices, Cameras, Imaging systems, CCD image sensors, CCD cameras, Signal to noise ratio, Computing systems, Data modeling, Image sensors

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Proceedings Article | 9 February 2001 Paper

Results of test flights with the airborne digital sensor ADS40

Anko Boerner, Ralf Reulke

Proceedings Volume 4169, (2001) https://doi.org/10.1117/12.417117

KEYWORDS: Sensors, CCD image sensors, Charge-coupled devices, Data processing, Aerospace engineering, Radiometric resolution, Advanced distributed simulations, Image processing, Image quality, Data modeling

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Proceedings Article | 27 October 1999 Paper

Simulation of APEX data: the SENSOR approach

Anko Boerner, Michael Schaepman, Daniel Schlaepfer, Lorenz Wiest, Ralf Reulke

Proceedings Volume 3753, (1999) https://doi.org/10.1117/12.366285

KEYWORDS: Sensors, Remote sensing, Sensing systems, Atmospheric optics, Ray tracing, Computer simulations, Atmospheric modeling, Reflectivity, Systems modeling, Data modeling

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Proceedings Article | 16 October 1998 Paper

Fusion of hyperspectral (DAIS 7915), wide-angle (WAAC),and SAR (E- SAR) data acquistion methods: the MultiSwiss '97 campaign

Michael Schaepman, Mathias Kneubuehler, Erich Meier, Andreas Mueller, Peter Strobl, Ralf Reulke, Ralf Horn

Proceedings Volume 3438, (1998) https://doi.org/10.1117/12.328125

KEYWORDS: Calibration, Synthetic aperture radar, Cameras, Data acquisition, Sensors, Imaging systems, Reflectivity, Visualization, Aluminum, Global Positioning System

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Proceedings Article | 15 December 1995 Paper

Optimization of a spaceborne sensor for the determination of cloud speed and height with a numerical simulation system

Norbert Reulke, Ralf Reulke, Herbert Jahn

Proceedings Volume 2583, (1995) https://doi.org/10.1117/12.228586

KEYWORDS: Clouds, Sensors, Cameras, Atmospheric modeling, Planets, Signal processing, Computer simulations, Mathematical modeling, CCD cameras, Numerical simulations

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Proceedings Article | 23 August 1995 Paper

Comparison of image reconstruction algorithms

Ralf Reulke

Proceedings Volume 2572, (1995) https://doi.org/10.1117/12.216936

KEYWORDS: Point spread functions, Digital filtering, Image restoration, Reconstruction algorithms, Cameras, Optical filters, Image processing, Imaging systems, Fractal analysis, Algorithm development

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