The Universal Software Radio Peripheral USRP NI2920, a software defined transceiver so far mainly used in Software Defined Radio applications, is adopted in this work to design a high resolution L-Band Software Defined Radar system. The enhanced available bandwidth, due to the Gigabit Ethernet interface, is exploited to obtain a higher slant-range resolution with respect to the existing Software Defined Radar implementations. A specific LabVIEW application, performing radar operations, is discussed, and successful validations are presented to demonstrate the accurate target detection capability of the proposed software radar architecture. In particular, outdoor and indoor test are performed by adopting a metal plate as reference structure located at different distances from the designed radar system, and results obtained from the measured echo are successfully processed to accurately reveal the correct target position, with the predicted slant-range resolution equal to 6 m.
Abstract:Holotomographic microscopy (HTM) measures the refractive index (RI) tomograms of living cells and tissues in three dimensions. The ability to observe biological processes at high spatial and temporal resolution opens uncharted territories for cell biologists, however, current HTM devices have a limited throughput. We show here the first automated multi-well plate-compatible HTM device, the CX-A. Thanks to state-of-the-art environment control and a new type of autofocus, the CX-A can record multiple conditions in parallel over large fields of view, while its software EVE supports automated single-cell segmentation and quantification. This opens the door to new applications for HTM, from drug screening to systems biology.
A new approach is proposed for the analysis and design of a planar Fabry-Perot antenna. The complete modal analysis of the field into the cavity leads to a simplified equivalent circuit, able to provide a reliable description of the coupling with the feeding waveguide, as well as to compute the equivalent currents on the radiating apertures, thus obtaining the radiated far-field. The proposed approach is preliminary validated on a metallic FabryPerot antenna structure. Then, a modified configuration, based on a cavity partially-filled with a dielectric substrate, is assumed to obtain a Fabry-Perot antenna with improved bandwidth features. Experimental validations on array prototypes are successfully discussed.
Este trabajo propone un sistema de medición de riesgo en zonas de desprendimiento de tierra con tecnología SDRadar. El prototipo fue desarrollado en un ambiente de laboratorio en la ESPOCH de Ecuador, con la utilización de una USRP B210 que trabaja a 5 GHz, se ha incluido dos amplificadores ZJL6G+ en cascada con 20dB de ganancia total para mejorar la potencia total del sistema. En la etapa de mediciones, se usaron 3 muestras de distinto material con diferentes niveles de humedad para determinar el riesgo en diversas condiciones. Estos materiales fueron macadam, tierra y arena. En dependencia de sus niveles de humedad, los riesgos oscilan entre valores máximos y mínimos, dónde una alta humedad conlleva a un alto riesgo y viceversa. El macadam fue el mejor material para un área de derrumbe debido a que presenta un menor índice de permitividad, esto da como resultado el menor riesgo. Los resultados fueron procesados para obtener los valores de reflexión y permitividad de los materiales y fueron guardados en una base de datos para analizar y determinar los niveles de riesgo, mediante simulaciones de desprendimientos de tierras como función del nivel de humedad.
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