Optimal vibration analysis for a combustion motor. - In: Proceedings of the 16th IEEE Conference on Industrial Electronics and Applications (ICIEA 2021), (2021), S. 166-170
Combustion motors have quite important uses in Peru due to capacity of energy that is achieved to solve multiple tasks, such as for example public transport, mining and factories. However, a big disadvantage is given owing to pollution that is produced through them. Therefore, there are many proposal solutions as for example, optimal control over physical variables, which have information of consumed fuel. Nevertheless, it gets complications in interesting (but longer) algorithms as strategies. That is the reason, why in this research is proposed a mathematical procedure that is correlated with faster and robust sensors/actuators according to achieve an enhancement performance over the efficiency of combustion motors.
https://doi.org/10.1109/ICIEA51954.2021.9516132
Active noise cancellation techniques to enhance audition in noisy cities. - In: 2021 IEEE International Conference on Mechatronics and Automation, (2021), S. 148-151
It is proposed in this research some suggestions and applications to enhance and care of the hearing health in noisy cities, such as for example, the noise that is caused by traffic, engines from factories and imprudent behavior from drivers and street sellers (as it happens in Peruvian cities). In this research, it was analyzed many techniques according to propose enhancement of the health audition by engineering analysis of the noise cancellation and advanced sensors/actuators (microphones and loudspeakers) that were based in nanostructures, because to achieve this objective. Therefore, it is expected that this research could be a support for institutions, which need technical analysis results, regarding to study the necessity to care the hearing health in noisy cities, such as for example, many hospitals, homes, universities and schools that are located near noisy avenues cannot get attenuation of noise, if there are not noise cancellation systems to care the hearing health.
https://doi.org/10.1109/ICMA52036.2021.9512571
Bi-static reflectivity measurements of microwave absorbers between 2 and 18 GHz. - In: 2021 Antenna Measurement Techniques Association Symposium (AMTA), (2021), insges. 6 S.
In anechoic chambers, the level of spurious reflections is determined by the reflectivity of the installed absorbers and is usually estimated using ray-tracing methods. But since the basic assumption of a purely specular reflection in most of these ray-tracing methods can lead to insufficient results, the reflectivity of the absorbers must be analyzed for oblique incidence and over a broad range of observation angles. In this paper, a bi-static measurement setup is proposed, which overcomes angular limits of the NRL-arch method and allows to analyze the scattering behavior of absorbers in an extended angular range. Using this setup, and applying the radar cross-section method, the reflectivity of two types of pyramidal absorbers was analyzed with respect to different illumination and observation angles for parallel and perpendicular polarization between 2 and 18 GHz. While the measurement results for normal incidence agree well with the specifications, additional non-specular reflections of similar strength were detected in the time-domain at different observation angles. Especially for the case of oblique wave incidence, it becomes apparent that the highest reflectivity does not necessarily occur for specular reflection. These findings help to improve the understanding of the scattering behavior of absorbers in general, as more comprehensive analyses become possible with this method.
https://doi.org/10.23919/AMTA52830.2021.9620601
Simulation and measurement of locomotive antennas in the installed state based on a scaled mockup. - In: 2021 Antenna Measurement Techniques Association Symposium (AMTA), (2021), insges. 6 S.
Accurate characterization of locomotive antennas is key to safe and robust railway signaling and control communication. With the introduction of new technologies and the foreseeable migration from the GSM-R standard towards FRM CS, new wireless applications and specifications arise, and suitable antenna solutions need to be developed and tested. Moreover, the rooftops of modern locomotives present a dense and harsh environment; therefore, potential antenna mounting spaces should be carefully evaluated to avoid undesirable degradations of the antenna radiation patterns. Due to the electrically large and complex structure of locomotives, full-scale testing is challenging to perform, especially under laboratory conditions. Antenna measurements with geometrically scaled models present a powerful alternative to address this issue. In this paper, we present and discuss antenna measurement results of a scaled locomotive mockup. The mockup incorporates two different cabin geometries, one with a step-like rooftop contour, and one with a smooth slightly tilted geometry. First, the optimum scaling factor was identified and validated through numerical simulations. Afterwards, antenna measurements with a scaled locomotive mockup were carried out in our automotive antenna measurement facility VISTA. The measured results were compared with the numerical simulations, where a good correlation above 80 % was found. Secondly, the impact of the rooftop geometries, and superstructures on the roof has been investigated for a range of operational frequencies between 700 and 2600 MHz. The results reveal that the parasitic impact of the antenna environment becomes more pronounced at higher frequencies.
https://doi.org/10.23919/AMTA52830.2021.9620626
Precise phase center localization of automotive LTE antennas in the installed state through phaseless LTE uplink measurements. - In: 2021 Antenna Measurement Techniques Association Symposium (AMTA), (2021), insges. 5 S.
With the event of integrated and multi-standard wireless links, phaseless antenna measurements are attracting more and more interest in research. Especially in the context of connected and automated driving, antennas, frontends, and digital signal processing units merge into telematic units and require new methods for performance evaluation in the installed state. The measurement of the phase diagram and the exact absolute positioning of electrically large antennas, i.e., antennas interacting with the car body, present challenges for safety-relevant applications and reliable test methods. This paper describes a way to determine the position of automotive antennas in the installed state with sub-wavelength precision from phaseless measurements. Realistic L TE uplink signals were used as test signals as they would be transmitted by an active device in a real-world scenario. The localization algorithm is based on orthogonal power measurements of the transmitted signal on a cylinder surface and a non-linear optimization. By comparison with a conventional localization based on spherical far-field data, an accuracy of the approach of less than 1 cm was achieved, which is less than N16 at the considered frequency of 1870 MHz.
https://doi.org/10.23919/AMTA52830.2021.9620655
Bi-static RCS variations of pedal and wheel movements on bicycles between 1 and 10 GHz. - In: 2021 Antenna Measurement Techniques Association Symposium (AMTA), (2021), insges. 6 S.
One benefit of cooperative automated and connected driving lies in the fusion of multiple mobile wireless sensor and data transmission nodes, covering complementary technologies like radar, cellular and ad-hoc communications, and alike. Current developments indicate enormous potential to increase the environmental awareness through joint communication and radar sensing. In this respect, future channel models require knowledge of bi-static reflectivities of road users over a range of illumination and observation angles, both in the nearfield and in the far-field. To establish reference data and model such angle-dependent RCS variations, this paper deals with realistic pedal and wheel rotations of a bicycle based on electromagnetic simulations. In the simulation setup, idealized far-field conditions with plane-wave illumination and observation were assumed, while the angles covered the entire azimuth with 201 variations of the pedal and wheel positions. The fluctuation of the RCS is analyzed and discussed in terms of its probability density and cumulative distribution functions. Depending on the angular constellation, the range of the fluctuation varied between 1 dB and 14 dB, while the specular reflection and forward-scattering showed almost no fluctuation.
https://doi.org/10.23919/AMTA52830.2021.9620542
Preprocessing of freehand ultrasound synthetic aperture measurements using DNN. - In: 29th European Signal Processing Conference (EUSIPCO 2021), (2021), S. 1401-1405
Manual ultrasonic inspection is a widely used Nondestructive Testing (NDT) technique due to its simplicity and compatibility with complex structures. However, in contrast to the data acquired using a robotic positioner, manual measurements suffer from perturbations caused by a variable coupling and a varying scanning density. Imaging techniques like the synthetic aperture focusing technique rely on an unperturbed dense measurement from an equidistant measurement grid. Consequently, imaging based on freehand measurements leads to artifacts. This work aims at reducing such artifacts by preprocessing the manual measurements using Deep Neural Networks (DNN). The training of a DNN requires a large set of labeled measurements which is difficult to obtain in NDT. In this work, we present a technique to train the DNN using only synthetic data. We show that the resulting DNN generalizes well on real measurements. We present an improvement in Generalized Contrast to Noise Ratio by a factor of 20 and 3 compared to omitting the preprocessing for synthetic and measurement data, respectively.
https://doi.org/10.23919/EUSIPCO54536.2021.9616155
Wafer-level fabrication of an EWOD-driven micropump. - In: MikroSystemTechnik, (2021), S. 574-577
Dimensioning and characterisation of an EWOD-driven chipintegrated micropump using time-resolved simulations. - In: MikroSystemTechnik, (2021), S. 531-534
Simulation model and dimensioning of a photoacoustic sensor for the detection of radiation-induced pressure surges. - In: MikroSystemTechnik, (2021), S. 523-526