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Railway applications are in continuous evolution with the aim of offering a more efficient, sustainable, and safer transportation system for the users. Generally, these applications are constantly exchanging information between the systems onboard the train and the trackside through a wireless communication. Nowadays, Global System for Mobile communications-Railway (GSM-R) is the technology used by European Train Control System (ETCS), but it is becoming obsolete. Therefore, alternatives for this technology have to be found for the different railway applications. Its natural evolution is to move forward with the latest technology deployed: Long-Term Evolution (LTE), which the Public Land Mobile Networks (PLMN) have already deployed. Therefore, testing the performance of this communication technology in the railway environment could be useful to assess its suitability and reduce the cost of railway network dedicated deployment. In order to do that, a methodology to characterize the communication environment is proposed. The main goal is to measure geolocated impairments of any communication channel in a railway environment being able to determine its behavior of the different communication technologies and find out possible coverage issues. Moreover, it could help in the selection of suitable communication technology for railway. This paper presents a brief description of the communication for railways and its QoS parameters for performance measuring. Afterward, the testing methodology is described, and then, the communication channel measurement campaign on a real track in Spain where the railway environment is variable is presented (tunnels, rural/urban area…). Finally, the measurements and results on this real track in Spain are shown. The results provide suitability of the 4G technologies based on the delay requirements for the implementation of ETCS over it.

Nowadays, the wireless networks have an important role in the deployment of several means of transports, platforms and applications. In the particular case of roads and vehicle area, some ideas are starting gaining importance such as the autonomous vehicle. In order to reach this ambitious goal, the wireless networks are a strategic issue for the communication between vehicles (V2V) and between infrastructure and vehicles (V2I), generally known as vehicle-to-everything (V2X). In this current moment, the most deployed cellular network is LTE (Long Term Evolution), progressing to 5G technology. Because of this, this paper shows the measurement of the LTE technology and the phenomena that affects this technology at IP level. To reach this last goal, the on-site testing of a measurement system is needed allowing to quantify network impairments of a communication channel in a given road environment. In this paper, the system capable of measuring a communication channel is explained and it is shown how an on-site testing of the communication channel of a specific road has been measured in terms of the RTT network impairment. As well, the results of the measurement has been analysed and explained. Finally, some conclusions are presented.

Global Navigation Satellite System (GNSS) has become the main technology in terms of navigation technologies, as it ensures a worldwide absolute outdoor positioning. The transportation sector employs this technology to obtain a position, velocity and time solution for the corresponding outdoor application. When talking about indoor positioning, nevertheless, GNSS becomes an unreliable navigation technology, as the below-noise signals get obstructed. In these cases, the Ultra-Wideband (UWB) technology can be used as a navigation solution, as its anchor trilateration based radiofrequency positioning resembles GNSS’s principle and, depending on the anchor location, it can be used for indoor positioning. However, just like other radiofrequency based technologies, UWB is vulnerable to interferences and the multipath effect. With the aim of overcoming these drawbacks, this article discusses how to apply Fault Detection and Exclusion (FDE) techniques to avoid using faulty anchors when employing UWB in indoor/urban environments such as tunnels or train stations.