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Within the scope of an ESA-funded project the capabilities of fiber optic measurement systems for structural monitoring during launcher lift-off are evaluated. Measurement tasks like monitoring of dynamic processes like structural vibrations during launcher lift off clarify the need for highly robust interrogators that allow measurements at high frequencies. For this goal, a highly integrated fiber...
We report on technology, performance and reliability of state-of-the-art AlGaN/GaN MMICs for space applications. Our quarter-micron gate length HEMTs have breakdown voltages beyond 150 V and deliver 5 W/mm output power density at 30 V drain bias with 50% PAE at 10 GHz operating frequency. Packaged two-stage MMICs with 8 W output power for telemetry applications have a PAE above 40% with a lifetime...
The 0.1 µm AlGaN/GaN technology and design of two W-band power amplifiers in this technology are described. The dual-stage amplifier reaches an output power of 400 mW at 90 GHz at an operation bias of 20 V. Two designs with different driver to final stage gate width ratio are discussed. More than 10 dB of power gain is reached for a compression level of around 2 dB per stage.
The Beam Conditions and Radiation Monitoring System (BRM), is installed in CMS to protect the CMS detector from high beam losses and to provide feedback to the LHC and CMS on the beam conditions. The primary detector subsystems are based on either single crystal diamond sensors (BCM1F) for particle counting with nanosecond resolution or on polycrystalline diamonds (BCM2; BCM1L) for integrated signal...
A multi-frequency Electron Cyclotron Heating (ECRH) system is in operation at the ASDEX Upgrade tokamak, currently employing three depressed collector gyrotrons, operating at 105 and 140 GHz. The system offers a high flexibility for a variety of plasma heating and current drive experiments including remotely controlled fast beam steering and modulation.
The reliability and degradation mechanism of AlGaN/GaN single stage amplifiers after 10 GHz stress at a drain voltage of 42 V and channel temperatures above 250°C was investigated using electroluminescence (EL) imaging, infrared thermography, and TEM. The extrapolated median lifetime extracted from the Arrhenius plot is 5105 h at a channel temperature of 200°C, and the activation energy is 1.7 eV...
This paper reviews solutions for the modeling of vias in printed circuit boards. The focus is on two approaches: multiple scattering methods and equivalent circuit models. For each approach, the general concept is described, followed by examples of recently improved or newly developed implementations. The applicability to several kinds of via modeling tasks is summarized. Finally, a closer look is...
Solid state lasers in the visible spectral region have many possible applications like projection technology and spectroscopy [1,2]. In these fields the generation of green light is still a challenge. Recent projection devices generate green laser light by frequency doubling of near-infrared solid state laser radiation. A compact, simple, and efficient laser based projection device is not yet developed...
The growth in the capacity of electric power system creates a necessity demand on protection relaying systems. Optical current transducers (OCT) which are mainly single mode optical fiber subjected to Faraday rotation are used as replacement for EM transducers for their immunity to the EM interference. However, the sensitivity to currents depends on the Verdet constant which is low in optical fiber...
The energy efficiency of computer systems is influenced by many interdependent aspects. To asses the efficiency, typical benchmarks characterized the total power consumption of a computer system under certain domain specific workloads. For example, in case of the SPECPower benchmark the workload is a typical web server specific Java application. The contribution of individual components is usually...
We propose a new DRM architecture that utilizes a two-step enforcement process to enable strong security even in the case of a compromised DRM viewer. This is achieved by using novel cryptographic techniques of attribute-based encryption that make it possible to limit access to media to a subset of users that has to fulfill certain properties which are specified during the encryption process. We call...
Smart Grid and Smart Meter initiatives seek to enable energy providers and consumers to intelligently manage their energy needs through real-time monitoring, analysis, and control. We have developed an inexpensive FPGA implementation of a spectral envelope preprocessor. This FPGA permits cost-effective and richly detailed power consumption monitoring for individual loads or collections of loads. It...
In this paper, a solution for detecting scratches in old films and videos is presented. The focus is on automation and to enable fast, cost-effective processing of mass archives enabling a later reuse and repurposing. A common problem of line scratch detectors are the distinction of real scratches from strong vertical image features. Nearly all common solutions require a user interaction in the detection...
In this paper, a new robust approach for camera based lane recognition is presented. The tracking filter and the detection interact such that the tracking filter is used to place a region of interest for a detection of lane segments in various distances, and each successful detection is used to update the lane geometry in the tracking filter. A novel and time efficient detection algorithm is used...
In this poster, we present our outdoor AR game MoleARlert. The idea behind this research prototype was to exploit the enormous potential of AR in combination with classical game play based on the well-known game Lemmings by Psygnosis. Real players interact with virtual moles on a real playing field. The moles are guided through the hazardous environment to their final goal. The multiplayer game is...
This paper presents a novel approach for an online initial camera calibration to estimate the extrinsic parameters for vision-based intelligent driver assistance systems. The method uses the periodicity of dashed lane markings and velocity information to determine the extrinsic camera parameters: height, pitch and roll angle. A lane marking detector is utilized to convert the images of road scenes...
Trained detectors are the most popular algorithms for the detection of vehicles or pedestrians in video sequences. To speed up the processing time the trained stages build a cascade of classifiers. Thereby the classifiers become more powerful from stage to stage. The most popular classifier for real-time applications is Adaboost applied to rectangular Haar-like features. The processing time of these...
This paper presents a novel approach to obtain reliable and robust time-to-contact estimates from a monocular moving camera observing various obstacles. The algorithm utilizes interest points to measure the relative scale change of an obstacle and applies robust estimation techniques to combine the different measurements into one of three possible motion models. These include a model with constant...
In the field of OLAP and data warehousing, column stores and compressed main-memory data storage technology have successfully been implemented in products that enable a significant speed improvement of analytical queries with special performance requirements. We could soon see the majority of analytical workloads move to such main-memory based systems. Having one specialized OLAP DBMS explicitly aimed...
In synchrotron radiation sources short pulses of coherent THz radiation is emitted when the length of electron bunches becomes sufficiently small. A detector system based on a superconducting NbN ultra-fast bolometer with an intrinsic response time of about 100 ps was jointly developed by the University of Karlsruhe (Institute of Micro- and Nanoelectronic Systems) and German Aerospace Center (Berlin)...
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