Alejandro Fernández

Mr. Alejandro Fernández

ceit
orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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2 March 2020 in IEEE Access
Verified
Journal Article
Open access
PZPaul Zabalegui
Paul Zabalegui
GMGorka De Miguel
Gorka De Miguel
AFAlejandro Fernández
Alejandro Fernández
JMJaizki Mendizabal
Jaizki Mendizabal
JGJon Goya
Jon Goya
IAIñigo Adín
Iñigo Adín
The use of GNSS technologies has been spreading over time up to a point in which a huge diversity of applications require their use. Due to this demand, GNSS has turned into a more reliable technology, as multiple aspects of it have evolved. Integrity has become a vital aspect of being considered when using GNSS. The following document gathers and shows different aspects of integrity in terms of GNSS. The paper mainly focuses on the description of different receiver autonomous integrity monitoring methods. For this purpose, basic concepts and possible GNSS error sources (and their corresponding solutions) are introduced. Afterward, an explanation and a classification of the integrity monitoring techniques is given, where the fault detection and exclusion methods and different protection level computation formulas are analyzed.

31 December 2020 in Electronics
Verified
Journal Article
Open access
PDF file
MLMarkos Losada
Markos Losada
Ainhoa CortesAinhoa Cortes
Ainhoa Cortes
AIAndoni Irizar
Andoni Irizar
JCJavier Cejudo
Javier Cejudo
AFAlejandro Fernández
Alejandro Fernández
In this paper, we propose a flexible Fog Computing architecture in which the main features are that it allows us to select among two different communication links (WiFi and LoRa) on the fly and offers a low-power solution, thanks to the applied power management strategies at hardware and firmware level. The proposed Fog Computing architecture is formed by sensor nodes and an Internet of Things (IoT) gateway. In the case of LoRa, we have the choice of implementing the LoRaWAN and Application servers on the cloud or on the IoT gateway, avoiding, in this case, to send data to the Cloud. Additionally, we have presented an specific setup and methodology with the aim of measuring the sensor node’s power consumption and making sure there is a fair comparison between the different alternatives among the two selected wireless communication links by varying the duty cycle, the size of the payload, and the Spreading Factor (SF). This research work is in the scope of the STARPORTS Interconnecta Project, where we have deployed two sensor nodes in the offshore platform of PLOCAN, which communicate with the IoT gateway located in the PLOCAN premises. In this case, we have used LoRa communications due to the required large distance between the IoT gateway and the nodes in the offshore platform (in the range of kilometers). This deployment demonstrates that the proposed solution operates in a real environment and that it is a low-power and robust approach since it is sending data to the IoT gateway during more than one year and it continues working.

27 August 2023 in Sensors
Verified
Journal Article
Open access
PDF file
IMIker Moya
Iker Moya
AFAlejandro Fernández
Alejandro Fernández
PZPaul Zabalegui
Paul Zabalegui
GMGorka De Miguel
Gorka De Miguel
MLMarkos Losada
Markos Losada
JMJaizki Mendizabal
Jaizki Mendizabal
Traditionally, freight wagon technology has lacked digitalization and advanced monitoring capabilities. This article presents recent advancements in freight wagon digitalization, covering the system’s definition, development, and field tests on a commercial line in Sweden. A number of components and systems were installed on board on the freight wagon, leading to the intelligent freight wagon. The digitalization includes the integration of sensors for different functions such as train composition, train integrity, asset monitoring and continuous wagon positioning. Communication capabilities enable data exchange between components, securely stored and transferred to a remote server for access and visualization. Three digitalized freight wagons operated on the Nässjo–Falköping line, equipped with strategically placed monitoring sensors to collect valuable data on wagon performance and railway infrastructure. The field tests showcase the system’s potential for detecting faults and anomalies, signifying a significant advancement in freight wagon technology, and contributing to an improvement in freight wagon digitalization and monitoring. The gathered insights demonstrate the system’s effectiveness, setting the stage for a comprehensive monitoring solution for railway infrastructures. These advancements promise real-time analysis, anomaly detection, and proactive maintenance, fostering improved efficiency and safety in the domain of freight transportation, while contributing to the enhancement of freight wagon digitalization and supervision.

17 March 2022 in Electronics
Verified
Journal Article
Open access
PDF file
MLMarkos Losada
Markos Losada
IAIñigo Adín
Iñigo Adín
AFAlejandro Fernández
Alejandro Fernández
RRRoberto Carlos Ramirez
Roberto Carlos Ramirez
JMJaizki Mendizabal
Jaizki Mendizabal
The digitalisation of freight rail is an essential improvement to create modern functions that offer a cost-effective, attractive service and improved operational opportunities to operators. These modern functions need intelligence, detection, actuation and communications. For this, generally, it is possible to process raw data in the Edge and send meaningful data over a communication link. However, the power supply is not granted in a freight wagon and so low power strategies need to be adopted. This paper presents the implementation and testing of a wireless connected heterogeneous multiprocessing architecture. From the power consumption point of view, this system has been stressed by means of a generic FFT function to evaluate the different on-board computing devices that have been decided. From the communication point of view, the LPWAN LoRa technology has been tested and validated on robustness and coverage. Thanks to the heterogeneous nature of this architecture and its configurability, it allows us to propose the most suitable computing ressources, data analysis and communication strategy in terms of efficiency and performance for the functions that this wagon on board unit needs to host and support. With this approach, operation data are reported to the centralised freight driver assistant system.

29 July 2022 in IEEE Access
Verified
Journal Article
Open access
PZPaul Zabalegui
Paul Zabalegui
GMGorka De Miguel
Gorka De Miguel
AFAlejandro Fernández
Alejandro Fernández
JMJaizki Mendizabal
Jaizki Mendizabal
JGJon Goya
Jon Goya
IAIñigo Adín
Iñigo Adín
In the above article [1], the authors forgot to properly acknowledgment the Shift2Rail Joint Undertaking.