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En este trabajo de investigación se llevó a cabo la transmisión de señales OFDM, basadas en el estándar 5G New Radio, con el fin de establecer qué tanto los impedimentos óptico-inalámbricos afectan la comunicación en un escenario de transmisión de radio-sobre-fibra. Con el software Matlab se hicieron análisis cualitativo y cuantitativo de las degradaciones en la información debidas a un canal óptico-inalámbrico. Los resultados permitieron demostrar que es posible realizar transmisiones OFDM bajo los lineamientos de 5G New Radio garantizando bajas tasas de error de bits en el rango de 0 a 20 km de fibra óptica, designado para aplicaciones 5G New Radio de baja latencia.

We aim to establish the relationship between the stakeholders who are part of the Open-Access Ecosystem (OAE). The study was developed from an ecosystem approach, analyzing the actors and their relationships. As a result, we proposed a simplified view of the main components of an OAE and the relationships between them, which could be useful for understanding the roles of the different stakeholders and the implications that current and new policies and mandates could have for them.

RESUMEN Objetivo Analizar el impacto de la contaminación del aire por material particulado PM2,5 y su relación con el número de asistencias a entidades de salud por enfermedades respiratorias por medio de analítica de datos. Métodos Se analizaron datos del Área Metropolitana de Medellín, Colombia, ciudad ubicada en un valle estrecho densamente poblado e industrializado y que ha presentado episodios críticos de contaminación en los últimos años. Se analizaron tres fuentes de datos: datos meteorológicos aportados por el SIATA (Sistema de Alerta Temprana de Medellín y el Valle de Aburrá); datos de contaminación por material particulado PM2,5 aportados por SIATA; y reportes de los RIPS (Registros Individuales de Prestación de Servicios de Salud) aportados por la Secretaría de Salud. Resultados Se evidenció la relación entre la concentración de PM2,5 con las asistencias médicas por los diagnósticos de IRA, EPOC y asma. En un episodio crítico de contaminación por PM2,5, se encontraron los siguientes retardos en la atención médica: entre 0 y 2 días para el IRA, 0 y 7 días para el EPOC y 0 y 5 días para el asma. Discusión Se encontraron coeficientes de correlación que evidencian la asociación de la concentración de PM2,5 con las asistencias por los diagnósticos de IRA, EPOC y asma. La mayor correlación entre las tres morbilidades se presentó para el asma. La variable meteorológica de mayor correlación con la variable objetivo es la temperatura del aire para el caso de EPOC y asma. En el caso de IRA, la variable con mayor correlación es la velocidad del viento. Por otro lado, el día de la semana es una variable de gran importancia a la hora de realizar un estudio de atenciones por enfermedades. ABSTRACT Objective To analyze the impact of air pollution by PM2,5 particulate matter and its relationship with the number of attendances to health entities for respiratory diseases through data analytics. Methods Data from the Metropolitan Area of Medellín, Colombia, a city located in a densely populated and industrialized narrow valley and that has presented critical episodes of contamination in recent years, were analyzed. Three data sources were analyzed: meteorological data provided by SIATA (Early Warning System of Medellín and the Aburra Valley), PM2,5 particulate matter contamination data provided by SIATA, and RIPS reports (Individual Registers for the Provision of Health Services) provided by the health department. Results The relationship between the concentration of PM2,5 and medical care for the diagnoses of ARI, COPD and asthma was evidenced. In a critical episode of PM2,5 contamination, the following delays in medical care were found: between 0-2 days for IRA, 0-7 days for COPD, and 0-5 days for asthma. Discussion Correlation coefficients were found that show the association of the concentration of PM2,5 with the attendances for the diagnoses of ARI, COPD, and asthma. The highest correlation between the three morbidities was found for asthma. The meteorological variable with the highest correlation with the objective variable is air temperature in the case of COPD and asthma. In the case of IRA, the variable with the highest correlation is wind speed. On the other hand, the day of the week is a variable of great importance when carrying out a study of care for diseases.

Open government data (OGD) is a tool that enables better the transparency of public administration, empower citizens, generate knowledge, innovation, and boosting the economy. However, there are social and technical barriers that affect these benefits. On the other hand, although proposals analyzing the development of OGD have been defined, no attention has been paid to the components that are part of an open data ecosystem. This article provides an overview of the components that enable open data ecosystems to facilitate the opening and use of OGD. A systematic mapping of open data ecosystem research was conducted in this paper. The study found 223 papers, of which six papers were selected that passed the inclusion and exclusion criteria. On the other hand, it was found that an open data ecosystem should consider at least five components: 1) Political/legal framework; 2) Actors 3) Technological infrastructure; 4) Data, and 5) Standards or tools to facilitate data interoperability.

Open data is a movement that has gained worldwide political relevance as a strategy that supports active transparency, access to public information, and the generation of public, social, and economic value. To know the progress and results of open data initiatives, governments, working groups, international organizations, and researchers have proposed indexes and evaluation models. These measurements focus on the evaluation of aspects of the preparation, implementation, and impact of open data initiatives. In Colombia, the national government within the framework of its digital government policy defined the open data project. The progress in data openings is monitored through international indexes and the open government index, which focuses solely on the publication and use of open government data. This research deals with the evaluation of the preparation for the opening of data, in public entities that have not implemented an open data initiative. The study gives a general description of the evaluation of open data at the international and national level, identifies aspects to be considered to measure the preparation, and proposes a conceptual model of evaluation to measure the preparation in open data of a public sector entity. This proposal can be considered as a tool that generates information that supports the design and implementation of an effective open data initiative.

The open data movement is developing and has gained worldwide political relevance, resulting in a proliferation of proposals that assess the progress of open governance initiatives (OGD) in different countries. The evaluation of OGD is a subject that has been studied recently. In this study, we present a systematic mapping study to show the scopes, instrument, methods and political, technical and organizational dimensions that assess the OGD. The analysis reviewed studies published in SCOPUS between 2009 and 2018. We found that the scope of the 30 studies focuses on the evaluation of the implementation. Similarly, the main type of evaluation is the application of the initiatives, through Frameworks and indicators, in the political and technical dimensions. The above shows that it is possible to approach the evaluation of the preparation of the OGD as future work, as an instrument that supports public entities in identifying capabilities to implement an OGD program.

In this work, we present an interferometric polymer-based electro-optical device, integrated with an embedded double-monolayer graphene capacitor for biosensing applications. An external voltage across the capacitor applies an electric field to the graphene layers modifying their surface charge density and the Fermi level position in these layers. This in turn changes the electro-optic properties of the graphene layers making absorption in the waveguide tunable with external voltages. Simultaneously, it is possible to appreciate that this phenomenon contributes to the maximization of the light-graphene interaction by evanescent wave in the sensing area. As a result, it is obtained large phase changes at the output of the interferometer, as a function of small variations in the refractive index in the cladding area, which significantly increasing the sensitivity of the device. The optimum interaction length obtained was 1.24 cm considering a cladding refractive index of 1.33. An absorption change of 129 dB/mm was demonstrated. This result combined with the photonic device based on polymer technology may enable a low-cost solution for biosensing applications in Point of Care (PoC) platform.

Composite materials have been extensively used on new aircraft airframes because of their advantages over metallic materials. This represents a difficulty for damage detection, a vital task for safety on the aerospace industry, as most nondestructive testing techniques are not effective on these materials since those usually present internal failures like delaminations which are difficult to detect. A miniaturized strain acquisition and wireless transmission system is presented alongside with a novel technique for structural behavior assessment, based on the use of Fiber Bragg Gratings to measure strains and non-supervised classification techniques to recognize different operational conditions. Operational tests were performed on an Unmanned Aerial Vehicles wing's beam, made of composite materials with the sensors embedded during its manufacturing. Strain measurements were processed using an Optimal Baseline Selection methodology. The tests performed proved the system's capability to identify and separate different operational conditions for a healthy structure, based on the analysis of its strain fields. The implementation of this methodologies can lead to perform real-time damage detection on aerospace complex structures made of composite materials.

This document presents the results of an investigation carried out in order to know the characteristics of the data published by the municipalities that make up the Aburra Valley in Antioquia and its relationship with the strategic issues defined by the national government in terms of open data. To obtain the results, a methodology defined consisting of three phases: Identification of information of the entities, characterization of the publications and analysis of the results. Among the main results are that most of the published data are visualized in datasets and graphs, and focus on education and mobility issues. These results will serve to improve the open data programs of the municipalities studied, as well as for future research related to analysis in other territories of the country or as a starting point to define measurements of results and impacts of the use of open data.

Radio-over-fiber is a cost-effective support for the forthcoming 5G developments aimed to fulfill the ever-increasing demand for information. However, such systems are limited by transmission impairments that reduce the quality of communication. To enhance the system performance, an adaptive decision-feedback equalizer based on the least mean square algorithm is proposed in this work to compensate for frequency mismatch in the transmitter and receiver local oscillators in a radio-over-fiber transmission scenario when considering the latest 5G New radio standard. Simulation results in MATLAB exhibit a major impact from the equalization technique in improving the system performance in the presence of such a frequency offset, allowing the optical link to be extended from ∼100 km with no equalizer up to ∼690 km after equalization. Thus, it was demonstrated that the proposed adaptive equalization technique is a promising contender to enhance 5G-based Radio-over-Fiber data transmissions.

Public entities have high volumes of stored government data that serve as a source of information for their management, improve the provision of services and interaction with the community, generating social and economic value. Some public administrations, despite being interested in opening the data, have faced obstacles to disseminate them, especially when data are of poor quality. The objective of this paper is to present the importance of evaluating the quality of the data sets that comply with the open format and that are published by public entities for the use of the community, being the case study the public administration of the municipality of Sabaneta The level of quality of open government data is evaluated in three dimensions: Precision, integrity and consistency, to propose strategies and data quality indicators for the improvement of Open Government Data (DGA) to be published.

En este documento se analizaron los efectos lineales y no lineales introducidos por la fibra óptica en un sistema de transmisión WDM-PON utilizando el formato de modulación DPSK. El análisis se basó en el impacto del ancho de línea del láser sobre el BER para diferentes velocidades de transmisión, potencia transmitida y coeficientes de dispersión de la fibra óptica. El estudio se realizó mediante simulaciones en la herramienta computacional OPTSIM®. Se encontró que al incrementar la velocidad de transmisión es posible utilizar fuentes ópticas con un mayor ancho espectral utilizando el formato de modulación DPSK, reduciendo el costo del transmisor. Adicionalmente se comprobó que los efectos no lineales afectan en mayor medida los sistemas de transmisión cuando se utilizan fibras ópticas con coeficientes de dispersión cercanos a cero.

7 p. Los sensores de fibra óptica ofrecen bajo consumo de potencia y permiten medir variables físicas, químicas o biológicas de manera distribuida, aprovechando diferentes efectos de propagación a través de la fibra. En este artículo se presenta el diseño de una red de sensores de fibra óptica para la medición de desplazamientos en laderas de montañas, como un mecanismo de prevención de desastres. Se analiza el uso de tres alternativas de sensado: reflectometría en el dominio del tiempo, FBG (Fiber Bragg Grating) y el efecto Brillouin. The optical fiber sensors offer low power consumption, allowing the measurement of physical, chemical and biological variables in a distributed way, taking advantage of different effects of propagation through the optical fiber. In this article, we describe the design of a network of optical fiber sensors to measure mountain slide displacements as a mechanism for disaster prevention. We analyze three sensing alternatives: Time Domain Reflectometry (TDR), FBG (Fiber Bragg Grating) and the Brillouin effect. Medellín

An optical access network with LTE, optical data, and CATV signals is experimentally studied. Rx sensitivities of −27.5 dBm, −26 dBm, and −24 dBm were obtained at bitrates of 1.25 Gb/s, 2.5 Gb/s, and 10 Gb/s at BER=10−4; whereas Rx optical power of −27 dBm is needed at an EVM of 28.2% for LTE. The minimum spectral separation is also measured showing the effect of the high power CATV on the other two signals.

En este artículo se analiza el impacto del ancho de línea en el desempeño de una red de acceso óptica en la que se emplea el formato de modulación DPSK. Se demostró, mediante simulaciones, el efecto del ancho de línea sobre la BER (Bit Error Rate). Se analizó el desempeño para diferentes velocidades de transmisión y valores de dispersión en la fibra óptica. DPSK es un formato simple y de menor costo comparado con el uso de detección coherente, DPSK. Se encontró que puede emplearse un mayor ancho de línea al incrementar la tasa de bits, lo que significa un menor costo de implementación. Se propone a DPSK como el siguiente paso en la actualización de la red de acceso actual que emplea modulación en intensidad. // over the performance of an optical link in an optical access network that employs the DPSK modulation format. We use simulations to measure the BER when the linewidth of the optical transmitter changes. We analyze the link performance with different data bit rates and different dispersion values of the optical fiber. DPSK is a cheaper and simpler solution compared with coherent detection. We found that is required a higher linewidth when the bit rate increases. This implies a lower cost of implementation of the access network. In this case, DPSK could be the next stage to upgrade the intensity modulation format used in the access networks.

QPSK modulation format with electronic compensation is an alternative to increase the capacity and reach in the next generation passive optical networks (NG-PON), in response to demanding services and applications. We perform simulations to compare the performance of two electronic compensation techniques Constant Modulus Algorithm (CMA) and Backpropagation, in a NG-PON with QPSK modulation and coherent detection for the compensation of the chromatic dispersion. We use CMA in the access network to increase the data bit rate up to 40 Gb/s and the reach up to 33.5 km, reducing the computational requirements compared with Backpropagation. Resumen El formato de modulación QPSK junto a la compensación electrónica es una alternativa para incrementar la capacidad y alcance en las redes ópticas pasiva de próxima generación (NG-PON), en respuesta a la demanda de servicios y aplicaciones. En este documento se presenta la comparación mediante simulaciones del desempeño de dos técnicas de compensación electrónica: el Algoritmo de Módulo Constante (CMA) y el algoritmo Backpropagation en una red NG-PON con modulación QPSK y detección coherente para la compensación de la dispersión cromática de la fibra óptica. Se analiza el uso del algoritmo CMA en la red de acceso con el fin de incrementar la velocidad de transmisión hasta 40 Gb/s y el alcance hasta 33.5 km, reduciendo la complejidad computacional en comparación con el algoritmo Backpropagation.

En este documento, presentamos el modelado de un canal de fibra óptica mediante la resolución de la Ecuación No Lineal de Schrödinger (NLSE). Se presentan las dos formas de solución para la NLSE: la forma analítica y la forma numérica empleando el método SSF (Split–Step Fourier Transform). En la simulación se consideran efectos lineales como la dispersión cromática y los efectos no lineales. Uno de los efectos no lineal es el efecto Kerr, del que se derivan los efectos de auto modulación fase (Self Phase Modulation, SPM) y modulación de fase cruzada (Cross Phase Modulation, XPM). Los métodos de solución son empleados para simular y visualizar los efectos de propagación a través de la fibra óptica. Se analizan los efectos de propagación para un escenario de red de acceso óptica con fibra mono–modo estándar (Single Mode Fiber, SMF), con longitudes de fibra de 20 y 40 km y tasas de bits entre 1,25 y 100 Gbps. De otro lado, son presentados los fenómenos no lineales como dispersión estimulada de Raman (Stimulated Raman Scattering, SRS) y dispersión estimulada de Brillouin (Stimulated Brillouin Scattering, SBS). Se presentan las ecuaciones para modelar SRS. Se presentan resultados de simulación de la amplificación Raman en un escenario seleccionado.

When you have to choose what type of modulation is selected for an optical system, you must also decide the type of receptor to use and the cost benefit of its use. This paper presents the evaluation of two formats (BPSK and DPSK) with coherent detector and coherent differential detector for each format respectively, in order to determine which of the two types of receptor and modulation has better performance in PON access networks has 10Gbps.

With the increasing amount of information that is demanding by fixed and mobile users through the multiservice networks, the deployment of the optical segment in the access network is a critical issue, with impact in the cost and performance of the overall network. While TDM-Passive optical network (PON) is standardized, hybrid WDM/TDM-PON is now clearly seen as the next generation trend in the multiservice access. In this work we propose a dimensioning scheme for the deployment of multiservice hybrid WDM/TDM-PONs, using a heuristic method.

Space division multiplexing in multicore fibers is one of the most promise technologies in order to support transmissions of next-generation peta-to-exaflop-scale supercomputers and mega data centers, owing to advantages in terms of costs and space saving of the new optical fibers with multiple cores. Additionally, multicore fibers allow photonic signal processing in optical communication systems, taking advantage of the mode coupling phenomena. In this work, we numerically have simulated an optical MIMO-OFDM (multiple-input multiple-output orthogonal frequency division multiplexing) by using the coded Alamouti to be transmitted through a twin-core fiber with low coupling. Furthermore, an optical OFDM is transmitted through a core of a singlemode fiber, using pilot-aided channel estimation. We compare the transmission performance in the twin-core fiber and in the singlemode fiber taking into account numerical results of the bit-error rate, considering linear propagation, and Gaussian noise through an optical fiber link. We carry out an optical fiber transmission of OFDM frames using 8 PSK and 16 QAM, with bit rates values of 130 Gb/s and 170 Gb/s, respectively. We obtain a penalty around 4 dB for the 8 PSK transmissions, after 100 km of linear fiber optic propagation for both singlemode and twin core fiber. We obtain a penalty around 6 dB for the 16 QAM transmissions, with linear propagation after 100 km of optical fiber. The transmission in a two-core fiber by using Alamouti coded OFDM-MIMO exhibits a better performance, offering a good alternative in the mitigation of fiber impairments, allowing to expand Alamouti coded in multichannel systems spatially multiplexed in multicore fibers.

In this paper, we show numerical simulations for analyzing spatially multiplexed systems based on orthogonal frequency division multiplexing and multiple-input multiple-output Alamouti code in order to compare the performance of the transmission in a two-core fiber with low coupling, and in few-mode fiber with high differential group delay. These new fibers are the most recent alternatives used for improving the throughput of long-haul and high-speed optical fiber networks. We compare the bit-error-rate of two orthogonal frequency division multiplexing signals, after 100 km of optical fiber, considering only its linear effects. The first one uses an 8 phase-shift keying signal operating at 130 Gbps, and the second one uses a 16 quadrature amplitude modulated signal operating at 170 Gbps. Our results show a better bit error rate performance using a few-mode fiber, compared with a two-core fiber. Additionally, Alamouti code shows a better effectiveness for compensation of linear impairments in a two-core fiber in comparison with a few-mode fiber.

The increasing demand of fixed and mobile applications, and considering that smart grid imposes new requirements to the access networks, in this paper we present an optical access architecture to support home multiservice including smart grid applications. We propose a migration path based in a WDM passive optical network (PON) architecture for the next 10 years. Moreover, we compare the performance of each stage in terms of data bit rate requirements, bit error rate (BER) and jitter.

In this paper we discuss Split - Step Fourier and Finite Difference methods to solve the nonlinear Schrodinger equation (NLSE), including dispersion and Kerr's effect analysis in a pulse across a single mode optical fiber. To accomplish this analysis, we start from Maxwell's equations and optical channel simplifications necessary to find the NLSE.

In this paper, we show a novel pilot-aided phase channel estimation approach based on theoretical relation between chromatic dispersion and coherence bandwidth, for pilots allocation in an symbol multiplexed by orthogonal frequency division multiplexing and transmitted to optical fiber system. The method is implemented on Matlab® to make a linear interpolation between adjacent pilot carriers, which are separated by data, in the symbol. Our simulations use an optical bandwidth of 12.5 GHz and Fast Fourier Transform size of 128 to establish the number of pilots for having error free and suitable channel estimation for a fiber length up to 1000 km. In our simulations, we took into account the parameters of a standard single-mode fiber. We calculate the minimum number of pilot carriers for a suitable pilot-aided channel estimation based on the analysis of the symbol position in the constellation diagrams for QPSK and 16-PSK signals, which should be limited to a decision area. We show that the minimum number of pilots for suitable channel estimation is lower than the number of pilots for channel estimation with error free.

In this paper we present a comparison of the peak to average power ratio (PAPR) between ortogonal frequency division multiplexing (OFDM) based on fast Fourier transform (FFT) and Fast-OFDM (FOFDM) based on discrete cosine transform (DCT). It is shown that although the probability of PAPR is slightly higher for systems using the discrete cosine transform, the difference between the conventional OFDM and fast OFDM schemes are not significant as well has been presented in previous papers in the academic community, it is important to remark that the techniques used for PAPR reduction could be used in both schemes without significant performance differences.

The study of the propagation effects that currently limit the performance of optical communication networks, allows implementing techniques that increase the capacity such as optical phase modulation and digital signal processing compensation. In this article we analyze the chromatic dispersion and nonlinearities for intensity and phase modulated signals including data bit rates of 40 and 100 Gbps. The analysis is done employing numerical simulation techniques such as split step Fourier transform (SSF) and split step in the time domain (SSTD), to resolve the nonlinear Schrodinger equation (NLSE). We obtain the accuracy comparing with analytical results, and we analyze the SSTD method in different fiber link scenarios including phase modulation and high data bit rates.

In this paper we present performance results of a Gigabit-Passive Optical Network (G-PON) for different alternatives of implementation with data bit rates of 1.25, 2.5 and 10 Gbps in the downlink. The presented results allow to determine the kind of transmitter and receiver to use affecting the implementation cost of the access network.

This paper present a numerical simulation study of bending loss in planar optical waveguides, at wavelengths around 1550 nm, using the Beam Propagation Method (BMP), for the purpose to reduce the physical size of photonic components and for the design of on-chip optical components for communication systems.

This article presents the design of a baseband processor for software radio, which uses carrier synchronizer and bit detector-synchronizer circuits based on algorithms implemented in hardware, and an inverse tangent circuit based on the CORDIC algorithm. In this case, the functional blocks of the processor can be reconfigured to support multiple modulation formats and signal processing tasks in the digital domain.

Reliability is a key requirement in the aerospace industry. Therefore, structural health monitoring (SHM) applications using strain-field estimation and pattern recognition techniques are in development as an alternative to improve reliability and reduce maintenance costs, promising to ease damage detection on aerospace structures. However, some challenges need to be resolved before real implementation of these techniques. One of these challenges is to uncouple operational conditions changes in strain field from those related directly to damage. In this paper, the development of a strain measurement remote acquisition and transmission system on an unmanned aerial vehicle (UAV) using Fiber Grating Sensors (FBGs) is presented. Before flight testing, ground tests are carried out to emulate the dynamic loads that will be presented during flight. The strain data acquired are processed using unsupervised learning algorithms based on Self-Organizing Maps (SOM) and DS2L-SOM (density-based techniques) in order to classify different operational conditions. The results showed the capability of the system for classifying different load conditions for a UAV’s main beam.