INANOE Repositorio (Inst- Nacional de Astrofísica, Óptica y Electrónica
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Sistema de enlace para un transmisor y un receptor para un satélite tipo CANSAT
No full textEn este informe técnico se presenta la actividad que se realizó en el programa de servicio social de los alumnos, Retama Romero Silvio, Tecalero Zaldivar Antonio y Guadarrama Pérez José Antonio, en conjunto con la Dra. Sánchez Urrieta Susana de la Facultad de Ciencias de la Electrónica (FCE) de la Benemérita Universidad Autónoma de Puebla (BUAP); el estudiante de Doctorado Salvador Palacios Juan y el investigador Dr. Mendoza Torres Eduardo ambos del Instituto Nacional de Astrofísica Óptica y Electrónica (INAOE)
MEGARA cryogenic system: integration, characterization and CCD alignment
No full textMEGARA cryostat is part of an optical Integral-Field Unit (IFU) and Multi-Object
Spectrograph (MOS) designed to the 10.4m GTC (Gran Telescopio de Canarias) telescope
in La Palma, Spain. MEGARA (Multi-Espectrógrafo en GTC de Alta Resolución
para Astronomía) will provide to the scientific community the possibilities of covering
12.5” x 11.3” on the sky (in the sparse mode), and observing 100 objects in a 3.5’ x 3.5’
field of view (in the disperse mode), with an intermediate-to-high spectral resolution in
the range of R ~ 6000, 11000 and 19000.
This thesis project is focused on the Assembling, Integration and Verification
(AIV) phase of the cryogenic system, which was designed by the Astronomical Instrumentation
Group for Millimeter Wavelengths at the Instituto Nacional de Astrofísica,
Óptica y Electrónica (INAOE), with other MEGARA components at the Universidad
Complutense de Madrid (UCM). The main activities of this project included the complete
integration of the cryogenic system, its pressure and temperature characterization,
its integration with other MEGARA subsystems, the continuous monitoring of the
cryostat before the Laboratory Acceptance phase, and the installation and alignment of
the CCD within the cryostat, which operates at a temperature of 153K. The activities
were developed at INAOE and UCM
Comparación de la estructura orbital de NGC 4314 en potenciales numéricos obtenidos con Imágenes Infrarrojas
Get PDFEn este trabajo se calcula el potencial gravitacional de la galaxia NGC
4314 utilizando la Transformada Discreta de Fourier en Tres Dimensiones.
Previamente se probó la técnica de la Transformada de Fourier en el cálculo
de potenciales con tres distribuciones de masa finita: masa puntual, esfera
de densidad homogénea y cascarón esférico. Se obtuvieron diversos potenciales
empleando la imagen de la galaxia en la banda de 3.6 μm y variando
el parámetro de suavizado Ɛ de la Transformada de Fourier y la relación
masa-luminosidad que transforma los valores de la imagen a masas solares.
Los potenciales fueron descompuestos en sus componentes de Fourier usando
la Transformada de Fourier unidimensional y estas componentes fueron
comparadas con los resultados mostrados por Quillen et al. (1994)
Automatic assessment of motor dexterity for rehabilitation with a representation nonspecific on sensor
Get PDFPatient evaluation causes a great burden on medics and clinical staff. Given the increase in Cardiovascular Diseases (CVD), including stroke and traumatic injuries, this work presents a novel automatized solution to reduce the burden of patient assessment using computational tools such as representations, model selection, classifiers and multi-label classifiers
Potentials for high resolution optical spectral analysis and nonlinear apodization with two-phonon light scattering controlled by elastic waves with linear losses
Get PDFNew physical details inherent in the non-collinear two-phonon Bragg light scattering controlled by ultra-high frequency elastic waves of finite amplitude are studied in wide-aperture crystals exhibiting moderate linear acoustic losses. Recently, it had been demonstrated that Bragg regime of light scattering exhibits the specific acousto-optical nonlinearity with a set of unit-level maxima. Now, additionally to our previous analysis, we present an advanced analytical description of this phenomenon in the amplitude and frequency domains; and what is more, we orient it mainly at the second unit-level maximum. This nonlinearity together with the linear acoustic losses in an acousto-optical cell produces a new effect of nonlinear apodization. The light beam, leaving the cell, can suppress side lobes and grow the dynamic range within potential optical spectrum analysis. After that we characterize comprehensively an acousto-optical cell, made of calomel and working within the second maximum of two-phonon light scattering, as a dispersive optical component. Finally, the results of our proof-of-principal experiments with the calomel-made cell, operating in the chosen regime, are presented and discussed
PAPR Reduction and asynchronous multiplexing with CCK Non-maximally decimated filter banks in OFDM systems
Get PDFFirst is presented an introduction to mobile communications, OFDM (Orthogonal
Frequency Division Multiplexing), the FFT (Fast Fourier Transform), perfect reconstruction
and efficient implementation in filter banks, finalizing with channelizer
systems. The advantages and disadvantages of OFDM are elaborated in order to introduce
a principal subject of our investigation, which is the channelization technique
using non-maximally decimated polyphase filter banks based on the state-of-the-art
from the literature. The channelizer is designed using a polyphase structure followed
by an FFT block to modulate a prototype filter and thus implement N filters for the
price of one, reducing significantly the workload of the system.
Orthogonal Frequency Division Multiplexing (OFDM) is adapted to the channelizer
in order to test isolation between mobile stations (MS) when a communication
link is established with the base station (BS). Typical synchronization techniques used
in Wireless Local Area Network (WLAN) systems like frame detection and channel
estimation is employed to test the correct operation and performance of the entire
communication system.
Peak to Average Power Ratio (PAPR) is reduced by using a codification technique
based on polyphase complementary codes which is adapted to the OFDM modulator.
The results are verified by simulations in MATLAB, ModelSim and FPGA implementation.Primero se presenta una introducción a los sistemas de comunicación móvil, multiplexación por división de frecuencia ortogonal (OFDM), la transformada rápida de
Fourier (FFT), reconstrucción perfecta e implementación eficiente en bancos de filtros,
finalizando con sistemas de canalización. Las ventajas y desventajas de OFDM son
elaboradas de manera que se introduzca el principal tema de nuestra investigación,
el cual es la técnica de canalización utilizando bancos de filtros polifásicos diezmados
no-maximales basándose en la literatura actual. El canalizador es diseñado utilizando
una estructura polifásica junto con la transformada rápida de Fourier (FFT) para
modular un filtro prototipo y de esta manera implementar N filtros por el precio de
uno, reduciendo significativamente la carga de trabajo del sistema.
Multiplexación por división de frecuencia ortogonal (OFDM) es adaptado al canalizador
para probar el aislamiento entre las estaciones móviles (MS) cuando un
enlace de comunicación es establecido con la estación base (BS). Técnicas de sincronización típicas utilizadas en sistemas de redes de área local inalámbricas (WLAN)
como detección de trama y estimación del canal son empleadas para probar el correcto
funcionamiento y rendimiento del sistema de comunicación entero.
La relación pico a valor medio de potencia (PAPR) es reducido utilizando una
técnica de codificación basada en códigos complementarios polifásicos los cuales son
adaptados al modulador OFDM.
Los resultados son verificados por simulaciones en MATLAB, ModelSim e implementación en FPGA
Modelo flexible de movimiento de torso, brazo, antebrazo y muñeca
Get PDFHuman motion analysis is an open research area that focuses on explaining,
by using different kind of sensors, the movements made by a person
and how they are accomplished. An important task of this research area is
proposing computational models able to represent human motion.
People move differently from each other, and some factors such as the
age or loss of physical abilities change their motion patterns, for that, it
is necessary to develop, on one hand flexible methods and motion models;
i.e. able to represent the movements of several groups of people, and on the
other hand simple ones; i.e. based on unsophisticated instruments, such as
wearable systems.
The main goal of this research is proposing and implementing a flexible
motion model based on signals of wireless inertial sensors and an electromyograph
to represent the motion of the trunk, arm, forearm and wrist of
a person with or without motion impairments. This motion model could
be used as a tool to analyze in detail the motion of people to determine
quantitatively the differences in their range of motion.
The developed model represents the motion of ten degrees of freedom of
the body: three of the trunk, three of the shoulder, two of the elbow and
two of the wrist. Our motion model is divided into two parts, on one hand,
the first part consists of a kinematic model that uses the information given
by three inertial measurement units to represent the motion of the trunk,
arm and forearm. On the other hand, the second part consists of a model
based on an ensemble of classifiers able to represent the motion of the wrist
by analyzing characteristics obtained through the electromyographic signals
of the forearm.
Two experiments were conducted in order to validate both parts of us
motion model. For the kinematic model, a reaching task was used as case
study and movement trajectories were compared. Namely, the trajectories of
the nape, arm and hand of five healthy people and one apoplexy patient obtained
through our motion model and through an optical system comprising eight cameras used as our ground truth. For the model based on the ensemble
of classifiers six decision trees were generated. A classification task of
the movements of the wrist of fifteen healthy people was accomplished using
two different data distributions, a random distribution and a distribution
based on individuals.El análisis de movimiento humano es un área de investigación abierta
donde se busca explicar, a partir de diversos tipos de sensores, qué movimientos
realiza una persona y cómo los realiza. Una tarea importante de esta
área de investigación radica en proponer modelos computacionales capaces
de representar el movimiento humano.
La manera de moverse varía de una persona a otra, y algunos factores
como la edad o la pérdida de capacidades físicas modifican los patrones de
movimiento, por ello, es necesario desarrollar métodos y modelos de movimiento
flexibles, por un lado; es decir, con capacidad de capturar el movimiento
de varios grupos de personas, y simples por otro lado; es decir, que se
basen en instrumentos no sofisticados, como lo son los sistemas “vestibles".
El objetivo de esta investigación es proponer e implantar un modelo
de movimiento flexible basado en señales de sensores inerciales y un electro miógrafo inalámbricos para representar el movimiento del torso, brazo,
antebrazo y muñeca de una persona que tenga o no limitaciones de movimiento.
Este modelo de movimiento podría servir como una herramienta
para analizar de forma detallada el movimiento de las personas y así determinar
de manera cuantitativa las diferencias en sus grados de movilidad.
El modelo desarrollado representa el movimiento que generan diez grados
de libertad del cuerpo: tres del torso, tres del hombro, dos del codo y dos
de la muñeca. Nuestro modelo de movimiento se divide en dos partes, la
primera es un modelo cinemático que utiliza la información de tres unidades
de medición inercial para representar el movimiento del torso, el brazo y
el antebrazo. Y, por otra parte, se cuenta con un modelo basado en un
ensamble de clasificadores, el cual se encarga de representar los movimientos
generados por la muñeca al analizar características extraídas de las señales
electromiografícas del antebrazo.
Se realizaron experimentos para validar las dos partes de nuestro modelo
de movimiento. Para el modelo cinemático se utilizó una tarea de alcance
como caso de estudio y se compararon las trayectorias del movimiento de la nuca, del brazo y de la mano de cinco personas sanas y de un paciente que
sufrió una apoplejía obtenidas por medio de nuestro modelo cinemático y por
medio de un sistema óptico de ocho cámaras que sirve como nuestro ground
truth
Diseño y desarrollo de una estación meteorológica con micro-controlador de 8 bits
Get PDFSe documenta el diseño y desarrollo de una estación meteorológica que será empleada en mediciones de campo para medir la correlación de las condiciones atmosféricas respecto a las condiciones de propagación de las ondas electromagnéticas en el rango de las ondas milimétricas y las microondas
Sci-HI: Caracterización de la antena disco-cono para prueba de sitios
Get PDFEste documento presenta simulaciones y modelado de la antena disco-cono, que son realizadas para la caracterización de la antena, calculando su patrón de radiación en diferentes escenarios, distintos tipos de suelo, alturas, con y sin cuerpo humano en las cercanías. Esta información es crucial para entender la respuesta instrumental del analizador. La respuesta corregida permitirá comparar los datos de diferentes sitios
Calomel acousto-optical cell for spectroscopic applications using noncollinear two-phonon light scattering
Get PDFWe study potentials of a new wide-aperture crystalline calomel-made acousto-optical cell. Characterizing this cell is non-trivial due to the chosen regime based on an advanced non-collinear two-phonon light scattering. Recently revealed important features of this phenomenon are essentially exploited in the new cell and investigated in more detail. These features can be observed simpler in tetragonal crystals, e.g. calomel, exhibiting specific acousto-optical nonlinearity caused by the acoustic waves of finite amplitude. This parametric nonlinearity manifests itself at low acoustic powers in calomel possessing linear acoustic attenuation. The formerly identified additional degree of freedom, unique to this regime, is exploited for designing the cell with an eye to doubling the resolution due to two-phonon processes. We clarify the role of varying the central acoustic frequency and acoustic attenuation using that degree of freedom. Then, the efficiency of calomel is exploited to expand the cell’s bandwidth at the cost of its efficiency. Proof-of-principle experiments confirm the developed approaches and illustrate their applicability to innovative technique of optical spectrum analysis with the improved resolution. The achieved spectral resolution 0.205 Å at 405 nm and the resolving power 19,800 are the best to our knowledge for acousto-optical spectrometers dedicated to space or airborne operations