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In this work, we consider Reconfigurable Intelligent Meta-surfaces (RIMs) to provide effective beam steering functionality, while enhancing the coverage of the fifth generation (5G) users in a urban city mobility context. In particular, we enable communications in the millimeter wave (mmWave) frequencies, that can occur simultaneously with other 5G communications. The main objective of this paper is to demonstrate the feasibility and advantages of an integrated Computed Vision (CV) approach for tuning the meta-atom states of a RIM structure working at mmWave frequency band, without estimating the interferes' radio channel. In particular, the CV system will feed a logic unit running a Machine Learning (ML) algorithm to compute in real-time the coding schemes, namely the sequence of binary states associated to each unit-cell of the RIM, in order to obtain the target reconfigurable radiation pattern. Specifically, a Genetic Algorithm (GA) is introduced to derive the most suitable radiation pattern for Beam Steering application, based on the input of a CV infrastructure. Results show the feasibility of such a kind of system, with an higher coverage achieved in dense scenarios, by improving the robustness against the potential blockages introduced by the mmWave technology. Moreover, we demonstrate the system is robust against the inaccuracy introduced by the CV and GA.

In the last few years, the railway community has been working on the replacement of the GSM-R technology used in ERTMS/ETCS system. It is crucial to identify alternative communication technologies able to replace GSM-R guaranteeing the same requirements of QoS/QoE, security, and safety. For this purpose, the two most promising approaches are based on FRMCS and ACS systems. The Eu-Rail JU H2020 AB4Rail project (Alternative Bearer For Rail) aims to investigate the possibility of extending the set of communication bearers that can be integrated into the FRMCS/ACS systems. In this paper, the authors describe the main results obtained in AB4Rail research activities and adopted methodologies. From AB4Rail project investigations, it has emerged that the most promising candidates are: Free Space Optics (FSO) and innovative aerial communication technologies including LEO HTS satellites and HAPS.

The European train control system employs GSM-R for communications between trains and the command/control centers. GSM-R technology is quite old and will be replaced in the near future by other technologies offering less expensive solutions, especially for regional and local lines. This article investigates a new telecommunication solution based on multi radio bearers using cellular and satellite public networks as an alternative to the deployment of a dedicated infrastructure. A test campaign on a 300 km of rail line (about 10,000 km of tests) has been carried out to evaluate the performance of cellular and satellite networks in a railway environment. Test trial results presented and discussed in this article have been used to assess the performance of a multipath TCP protocol to effectively support multi-bearer communications. A discussion of the economic benefits and the potential industrial implications of the proposed solution concludes the article.