Smart optical imaging systems with automated electronics

In this dissertation, proposed and demonstrated are several novel smart electronically automated optical designs to efficiently solve existing real-world problems in the field of shape sensing and imaging. First half of the thesis proposes shape sensing techniques that use an Electronically Controlled Variable Focus Lens (ECVFL) within a smart optical design suitable for a wide range of applications including shape sensing and projection displays. The second part of this dissertation involves the use of the Digital Micromirror Device (DMD) deployed within several smart optical designs including an embedded laser beam profiler and a new camera idea which is inspired by the Telecommunication science field. Specifically, proposed and demonstrated is the design and implementation of the novel imaging device called Coded Access Optical Sensor (CAOS) where CAOS is able of operating with different application dependent working modes. Experimentally and successfully demonstrated for the first time are its use for coherent light laser imaging as well as for incoherent imaging of a high dynamic range white light scenario. It is also shown how its design can be further extended for multispectral and hyperspectral imaging applications

Agile wavefront splitting interferometry and imaging using a digital micromirror device

Since 1997, we have proposed and demonstrated the use of the Texas Instrument (TI) Digital Micromirror Device (DMD) for various non-display applications including optical switching and imaging. In 2009, we proposed the use of the DMD to realize wavefront splitting interferometers as well as a variety of imagers. Specifically, proposed were agile electronically programmable wavefront splitting interferometer designs using a Spatial Light Modulator (SLM) such as (a) a transmissive SLM, (b) a DMD SLM and (c) a Beamsplitter with a DMD SLM. The SLMs operates with on/off or digital state pixels, much like a black and white state optical window to control passage/reflection of incident light. SLM pixel locations can be spatially and temporally modulated to create custom wavefronts for near-common path optical interference at the optical detectors such as a CCD/CMOS sensor, a Focal Plane Array (FPA) sensor or a point-photodetector. This paper describes the proposed DMD-based wavefront splitting interferometer and imager designs and their relevant experimental results

Demonstration of 136 dB dynamic range capability for a simultaneous dual optical band CAOS camera

For the first time, proposed and demonstrated is a simultaneous dual optical band coded access optical sensor (CAOS) camera design suited for extreme contrast multispectral bright target scenarios. Deploying a digital micromirror devices (DMDs)-based time-frequency agile pixels CAOS-mode within a two point detector spatially and spectrally isolating framework, this imager simultaneously and independently detects pixel selective image information for two different broad spectral bands that further undergo independent spectral image data extraction via finer-tuned wavelength filtering using all-optical or CAOS-mode electronic filters. A proof-of-concept visible-near infrared band CAOS imager is successfully demonstrated using a target scene containing LEDs and engaging narrowband optical filters. In addition, using the CAOS-mode, demonstrated is the RF domain simultaneous color content monitoring of a white light LED image pixel. Also proposed is the use of a higher bit count analog-to-digital converter (ADC) with both range and sampling duration parameter control along with a larger data set electronic DSP to extract higher DSP gain and realize additional noise suppression. Using a 16-bit ADC and 2,097,152 point fast Fourier transform (FFT) digital signal processing (DSP) for a 633 nm laser engaged test target scene that is subject to nearly 7 decades (107) of gradual optical attenuation, the experimental camera demonstrates an agile pixel extreme dynamic range of 136 dB, which is a 56 dB improvement over the previous CAOS-imaging demonstrations

On the MIMO Capacity for Distributed System under Composite Rayleigh/Rician Fading and Shadowing

Wireless channels are commonly affected by short-term fading and long-term fading (shadowing). The shadowing effects must be taken into account also when mobility is present in the wireless scenario. Using a composite fading model, the total channel capacity can be studied for a scenario with short-term Rayleigh fading along with shadowing. This work provides quantitative results for these kinds of scenarios with Rayleigh fading and shadowing, considering also multiple-input and multiple-output systems, which have not been previously reported. In addition, the channel capacity has been studied in depth in its relation with the shadowing level, signal to noise ratio, and the number of elements in the multiple-input and multiple-output system. Moreover, the channel performance with shadowing has been compared to the one without it. Furthermore, Rician model with shadowing is studied and its results are reported. In addition, correlated and experimental results are provided. It is identified that the distributed MIMO systems can benefit from shadowing in Rician channels. This advantage has not been reported previously. This type of fading is proposed for massive MIMO by others and our results open the door to emulate massive MIMO on a reverberation chamber.This work has been supported by “Gobierno de Extremadura” with project number IB13113, PYR-2014 GENIL project (PYR-2014-CEB09-0010/MICINN), and CEIbioTIC project (mP_TIC_11)

China: el gigante ha despertado

“China es un gigante dormido. Dejadlo dormir porque, cuando despierte, el mundo se sacudirá” dijo Napoleón Bonaparte en 1816. Dos siglos después, el gigante ya ha despertado. Actualmente, la República Popular China es la segunda economía del mundo y ha logrado, sin dejar de lado su lugar como potencia regional en Asia, extender su poderío por los cinco continentes. De manera pacífica, y con el softpower como su mayor estrategia, ha sabido ganarse un lugar en la agenda política y económica de cada país con el cual ha iniciado vínculos diplomáticos. En el presente trabajo se analizará el camino recorrido por el gigante asiático en el siglo XX y su transición hacia el siglo XXI. Su sistema político, su relación con los países vecinos, Estados Unidos y Europa; y su política exterior para África, la región latinoamericana y la República Argentina serán los ejes centrales.‘China is a sleeping giant. Let her sleep, for when she wakes she will shake the world’ said Napoleon in 1816. Two centuries later, the giant has awakened. Currently the People's Republic of China is the second largest economy in the world and, without neglecting its place as a regional power in Asia, has extended its power to the five continents. Peacefully, and using the soft power as its main strategy, it has succeeded in gaining a place in the political and economic agenda of each country with which it has initiated diplomatic ties. In the present work the path traveled by the Asian giant in the 20th century and its transition towards the 21st century will be analyzed. The focus will be in its political system, its relationship with the neighboring countries, United States and Europe; and its foreign policy towards Africa, Latin American region and Argentina.Universidad Católica de Santa F

Circularly polarised broadband planar lightweight reflectarray with eligible pattern for satellite communications in Ku-Band

This study presents a lightweight planar patch-array reflectarray at Ku-band for satellite communications. The reflectarray is composed of two separate planar structures: the radiating interface formed by a planar multi-layered broadband patch array, and a phase shifting device formed by 3 dB/90° couplers. The radiating element is a multi-layered patch structure, designed to provide circular polarisation (CP). Each array cell phase is controlled by open-ended shifting lines of variable length connected to the 3 dB/90° couplers. The use of this kind of couplers maintains the same CP received/transmitted: the design imposes that if a right-hand CP (RHCP) [or left-hand CP (LHCP)] is received coming from the feeder, the same RHCP (or LHCP) configuration is re-radiated by the reflectarray. Additionally, the feeding horn can be moved in the x or y axes, so that the feeder angular position let re-define the radiation pattern and its pointing direction. Finally, measurements of a lightweight portable planar reflectarray prototype are provided and very good agreement is observed when compared with theoretical result

Broadband electronically tunable reflectionbased phase shifter for active-steering microwave reflectarray systems in Ku-band

This document provides the design of an electronically reconfigurable microwave phase shifter for reflectarray systems. The phase shifter is based on a hybrid coupler with reflective circuits in three ports. Each reflective circuit introduces a phase variation that can be modified due to the variable capacity value of a varactor inserted in it. The phase shifting process includes three different stages of phase shifting for the incoming signal in its way through the phase shifter: the signal is conducted through the device towards the reflective circuits in four different ways. The input port of the device is also the output one, providing the desired reflective phase shifting effect. This device is of great interest in reflectarray applications in order to provide more than 360° of controllable phase shifting at each array element. The document includes the complete design of the phase shifter along with its design parameters and circuital behaviour

Electronically reconfigurable reflective phase shifter for circularly polarized reflectarray systems

This letter presents the design of a two-port electronically reconfigurable phase shifter for circularly polarized reflectarray systems at microwave frequencies. The phase shifter is based on 3 dB/90? couplers combined with reflective circuits that introduce sequentially the phase variation. Each reflective circuit, formed by printed elements (L) and tunable varactors, produces the phase variation due to the variable capacity value of the varactor. The phase shifting process includes three different stages of phase shifting for the signal in its way from the input port towards the output port through the phase shifter. Both ports are interchangeable, acting either as input or output ports. This fulfils the reflection requirements of circularly polarized reflectarrays, being especially suitable for this purpose. The complete design, together with its circuital behavior and performance results, are depicted in this document

Glide-Symmetric Pin Phase Shifter implemented in Gap-Waveguide Technology

This paper presents a compact and low-loss waveguide phase shifter based on a pin lattice in glide- symmetric configuration. There is a significant increase in provided phase shift when using a glide-symmetric pin distribution instead of a non-glide-symmetric configuration. A prototype has been manufactured to validate the simulated results of both phase shifters: non-glide-symmetric and glide- symmetric designs. Gap-waveguide technology has been implemented for low-cost manufacturing. The measurement results demonstrate the higher performance and compactness of the glide-symmetric phase shifter. For the same phase shifter length, the glide-symmetric design provides around 80 degrees more of phase shifting compared to the non-glide-symmetric phase shifter. Both phase shifters have a good impedance matching between 46 and 60 GHz (better than -10 dB) and an insertion loss lower than 1 dB.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Metaheurísticas híbridas para el problema del apagado de celdas en redes 5G

La densificación masiva de estaciones base (BS) es una de las tecnologías facilitadoras bien reconocidas por la literatura para el desarrollo de la quinta generación de redes de telecomunicaciones (5G). Su implementación, sin embargo, que requiere el despliegue de miles de BSs por km^2, está en claro conflicto con uno de los requisitos de diseño de este tipo de redes, que pretende tener un 90% menos de consumo energético que la actual cuarta generación. Una forma de reducir el coste de estas redes ultradensas consiste en apagar un subconjunto de BSs de forma que minimice su consumo energético pero, a su vez, se maximice la capacidad de la misma. Es, por tanto, un problema de optimización multi-objetivo. En este trabajo se propone un nuevo operador específico para el problema que es capaz de mejorar considerablemente la efectividad de varios algoritmos multiobjetivo. Para ello, se han realizado experimentos con 9 escenarios de diferentes niveles de densificación tanto de BSs como de usuarios que muestran un comportamiento consistente y efectivo independientemente del algoritmo e instancia abordada.Este trabajo ha sido financiado parcialmente por el Ministerio de Economía y Competitividad y los fondos FEDER con los proyectos TIN2016-75097-P, TIN2014-56494-C4-3-P, TIN2017-85727-C4-2-P y TEC2015-68752. Francisco Luna también agradece la ayuda de la Universidad de Málaga, Campus de Excelencia Internacional Andalucía Tech, y el proyecto PPIT.UMA.B12017/15 del I Plan Propio de Investigación y Transferencia