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The presented work aims at development of a management evaluation system (condition monitoring) in the event of an explosion using a network of wireless sensors. The flow of information in the situation assessment system is made possible with the applied energy autonomous and energy-efficient wireless sensor nodes. Through this evaluation system, we will be able to do a real time assessment on the...
In this contribution we introduce a new approach for a piston temperature measurement system based on surface acoustic wave (SAW) resonators sensitive to temperature. The approach offers a new and competitive way to support the development of pistons and allows the research and improvement in combustion processes.
Numerous investigations of mobile radio communication have been conducted in environments such as urban, outdoor-to-indoor or indoor, only a few are in ruins. Within a running project, I-LOV, a study of a mobile radio propagation channel in urban search and rescue scenarios is conducted. Due to complex environment in ruins, great multipath interference can take place, which strongly impacts communication...
In this contribution a radar assisted method is presented for the search for persons buried e.g. in collapsed buildings. Classical detection technology covers borescopes and geophones in combination with K-9 units (search and rescue dogs) for search and rescue missions in ruins, detritus and cones of debris. An improved and time efficient approach for search of vital signs can be realized with UWB...
In this contribution we discuss the first results of a running project1, I-LOV, within the German national research program for civil security funded by the German Federal Ministry of Education and Research (BMBF) concerning improved time efficiency and reliable novel detection systems for search and rescue. Classical detection technology covers borescopes and geophones in combination with K-9 units...
In our previous research we already demonstrated micro acoustic devices, such as membrane based thin film bulk acoustic shear wave resonators and surface acoustic shear wave resonators, based on metal-organic-vapour-phase-epitaxial (MOVPE) grown highly oriented a-plane piezoelectric material. Although MOVPE is a well established process for compound semiconductor layer growth especially of III-V semiconductors...
In this work, the continuous wavelet transform (CWT) is used to analyze periodic motions, measured by contactless Doppler radar, which have small amplitudes, drifting frequencies and dropouts. Using a classical method like fast Fourier transform (FFT) for periodic signals results in loss of the time behavior of the signal, drifting frequencies and dropouts, causing distortion in the frequency peaks...
In this paper, electron-beam (e-beam) lithography for processing of surface acoustic wave devices is investigated, and its suitability for large-scale processing discussed. Electron-beam lithography is used for exposure of surface acoustic wave (SAW) resonator patterns on polymethyl methacrylate (PMMA) coated piezoelectric substrates. Electron-beam lithography can be used for high frequency SAW designs,...
Metal-Organic-Vapor-Phase-Epitaxy (MOVPE) is a well established process for compound semiconductor layer growth especially of III-V semiconductors as InP, GaAs, and the nitrides GaN or AlN. In the case of the nitrides one can obtain highly oriented a-plane piezoelectric material, well suited for shear-microwave applications, by tilting the c-axis of the piezoelectric unit cell by 90deg to result in...
This paper focuses on metal-organic-vapor-phase-epitaxial (MOVPE) grown on a-plane gallium-nitride (GaN), representing a novel approach for piezoelectric materials with good prospects for quartz-crystal-microbalance (QMB), like sensors with respect to its biocompatibility and frequency filter applications. Material characteristics of gallium-nitride as well as the processing of shear wave resonators...
The mass sensitive effect of RF-filter technology based film and a solidly-mounted acoustic bulk wave single resonator (FBARs and SBARs) is investigated for metrological use. For a high resolution of a sensor system all systematical errors like cross temperature sensitivity must be eliminated. A high quality factor Q is needed for stable oscillating for minimizing statistical errors. Experiments using...
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