Martha Cecilia Paredes Paredes

Roadside-unit (RSU) deployment models need data that tell which vehicles can reach each candidate RSU, in which mobility snapshot, and with how many hops. Producing these data is not trivial: it means combining traffic mobility, urban geometry, direct-link evaluation, graph processing, and optimization-oriented data structures. This paper presents a web platform that turns a geographical area and a SUMO mobility scenario into an optimization-ready connectivity dataset. The backend integrates OpenStreetMap and SUMO tools, filters candidate RSU positions, evaluates binary V2V and V2I links from communication range and building obstruction, and computes cumulative and minimum-hop connectivity through a matrix recurrence. A formal proposition justifies the recurrence used by the pipeline: it recovers every vehicle–RSU relation within a given hop limit, while first-arrival matrices identify the minimum hop count. A Streamlit frontend supports configuration, execution, visualization, and export. On the Historic Centre of Quito, varying the minimum junction degree and the clustering radius keeps between 14 and 393 of 1211 eligible junctions as candidates (about 68% to 99% reduction). The workflow separates mobility simulation from infrastructure optimization, so the same dataset can feed different exact or heuristic deployment models.

This paper presents a practical guideline to implement and evaluate time and frequency diversity techniques in Orthogonal Frequency Division Multiplexing (OFDM) systems under Rician fading using MATLAB R2024a. The MATLAB framework allows flexible configuration for several parameters, such as modulation schemes, cyclic prefix lengths, and channel parameters. We present the results in terms of Bit Error Rate (BER) versus Signal-to-Noise Ratio (SNR) and Power Spectral Density (PSD). Our software aims to facilitate the study of different diversity techniques in OFDM systems for both academics and students.

The 5th-Generation New Radio (5G-NR) network have been widely deployed around the world in the frequency range 1/range 2 bands. Once specific frequency bands within these ranges can vary across different countries and regions due to regulatory differences, it should be carried out radio network planning to evaluate the 5G coverage considering the particularities of different locations. In this regard, this paper performs a throughly analysis of the following methods for modeling wireless channel propagation in Quito, Ecuador: 3rd Generation Partnership Project, Knife Edge Diffraction (KED), ASTER and Dominant Path model (DPM). Specifically, we focus on KED, ASTER, and DPM for $3.5/28$ -GHz bands to determine the propagation models in three-Dimensional urban macro scenarios. In the radio network planning, the multiple-input multiple-output array antennas, $2\times 2/ 4\times 4$ configuration radiation patterns are deployed using WINPROP tool and $64\times 64$ array configuration with the ATOLL tool. 5G frequency specifications, path-loss, influence of diffraction, reflection, blocking, and fading between transmitter and receiver have been considered for scenarios of interest, such as dense urban and urban in Quito, by using fixed wireless access applications and Vehicular-to-Everything (V2X) communications. In addition, data rates, throughput, and the quality metrics of the received reference signal, i.e., the signal-to-noise plus interference ratio, the reference signal received quality, the reference signal received power, and the received signal strength indicator, are also assessed for each propagation model. Finally, we provide useful insights into propagation models and design usage rules for the bands mentioned in 5G networks for Quito city.

This article presents the implementation and the evaluation of a transmission–reception system for Physical Downlink Control Channel (PDCCH) within the context of fifth-generation cellular networks (5G/NR). The research focuses on characterizing the behavior of the PDCCH channel concerning different User Equipment (UE) positions through simulations conducted in MATLAB. Two scenarios are considered: a lossless system and a system with losses, where the outcomes are presented in terms of Bit Error Rate (BER) vs. Signal to Noise Ratio (SNR) and BER vs. Transmit Power, respectively. One contribution of the paper is the explanation transmission–reception system for PDCCH in MATLAB, while the second contribution is the presentation of simulation results. From results, it was deduced that higher UE height corresponds to improved channel performance, greater UE elevation angle leads to enhanced channel performance, and increased carrier frequency results in reduced performance of the physical control PDCCH channel.

By recognizing the tremendous flexibility of the emerging fluid antenna system (FAS), which allows dynamic reconfigurability of the location of the antenna within a given space, this paper investigates the performance of a single-antenna FAS over spatially correlated Nakagami-m fading channels. Specifically, simple and highly accurate closed-form approximations for the cumulative density function of the FAS channel and the outage probability of the proposed system are obtained by employing a novel asymptotic matching method, which is an improved version of the well-known moment matching. With this method, the outage probability can be computed simply without incurring complex multi-fold integrals, thus requiring negligible computational effort. Finally, the accuracy of the proposed approximations is validated, and it is shown that the FAS can meet or even exceed the performance attained by the conventional maximal ratio combining (MRC) technique.

By recognizing the tremendous flexibility of the emerging fluid antenna system (FAS), which allows dynamic reconfigurability of the location of the antenna within a given space, this paper investigates the performance of a single-antenna FAS over spatially correlated Nakagami-$m$ fading channels. Specifically, simple and highly accurate closed-form approximations for the cumulative density function of the FAS channel and the outage probability of the proposed system are obtained by employing a novel asymptotic matching method, which is an improved version of the well-known moment matching. With this method, the outage probability can be computed {simply} without incurring complex multi-fold integrals, thus requiring negligible computational effort. Finally, the accuracy of the proposed approximations is validated, and it is shown that the FAS can meet or even exceed the performance attained by the conventional maximal ratio combining (MRC) technique.

Bluetooth es una tecnología inalámbrica abierta, de corto alcance y de baja potencia, cuyo objetivo es simplificar la comunicación entre diferentes tipos de dispositivos. Bluetooth tiene cinco versiones, divididas en dos modos de funcionamiento principales, Classic Bluetooth y Bluetooth Low Energy (BLE). BLE está diseñado para el uso de aplicaciones IoT (Internet of Things - Internet de las Cosas). La quinta versión de Bluetooth mejora todas las prestaciones para superar a otras tecnologías que quieren ser la base de las comunicaciones IoT. Bluetooth 5 logra mayor alcance, mayor velocidad de transmisión de datos, soporte mejorado para anuncios y eficiencia energética que las versiones anteriores. La nueva función de topología de malla hace que Bluetooth sea un buen candidato para las comunicaciones de Internet de las Cosas, ya que permite arquitecturas descentralizadas. En este trabajo se realiza una revisión de la versión 5 de Bluetooth. Además, se presentan los requisitos de operación de IoT, basados en las recomendaciones de la UIT (Union Internacional de Telecomunicaciones). La contribución de este trabajo es el análisis de las características de Bluetooth 5 para determinar si cumplen o no con los requisitos de IoT propuestos por la ITU. Los resultados del análisis indican que Bluetooth 5 cumple con los requisitos de alto nivel y aproximadamente la mitad de los requisitos de IoT estándar de cada categoría.

Network simulators are used for the research and development of several types of networks. However, one of the limitations of these simulators is the usage of simplified theoretical models of the Packet Error Rate (PER) at the Physical Layer (PHY) of the IEEE 802.11 family of wireless standards. Although the simplified PHY model can significantly reduce the simulation time, the resulting PER can differ considerably from other more realistic results. In this work, we first study several PER theoretical models. Then, we propose a curve fitting algorithm, which is able to obtain a fast and accurate approximation of other PER models. The curve fitting algorithm uses simulated data as input and outputs the coefficients of a simple model that offers a very accurate approximation of the original PER. Finally, we implemented this approximation in the ns-3 network simulator, thus obtaining high realism since now we can select several theoretical PER models or even a more realistic scenario with the effect of the high Peak-to-Average Power Ratio (PAPR) in the signal. The ns-3 results show how the selection of the PER model at the PHY can significantly impact the Packet Loss Rate (PLR) of a scenario composed of a linear chain of several nodes, one of the simplest multi-hop scenarios.

5G is a new technology that amply evolves previous cellular network technology. The 3rd Generation Partnership Project (3GPP) has been continuously publishing the specifications for 5G on Releases; starting in 2019 with Release 15 and recently publishing further improvements on Release 17 (2022). Despite the features and benefits of 5G, its accessibility for professionals has some challenges. These include the very technical language used in the Releases, the high quantity of specifications within a Release, and the lack of technical information available online. These challenges are highly important to professionals in Telecommunications that need to access, read, understand and apply this technology. In this article, we describe the implementation of a collaborative website, which aims to share and collect information about 5G in form of articles and simulations provided by the community of users. For guaranteeing an appropriate way to show this valuable information, the construction of this website has followed a recognized process for defining information architecture.