Multi-element arrays in subway environments

Laburpena

In 2005 the construction of the new subway line began Barcelona L9 network. With this subwa line the newest and longest subway line in Europe is born, connecting the city of Barcelona fro its North-West part to its airport. This subway line includes a new wireless communication deployment devoted to provide ground-to-carriage communication services which are related with automatic control train, train monitoring, personal communications and video surveillance. In 2007 Infraestructures Ferroviàries de Catalunya signed an agreement with the Universitat Politècnica de Catalunya which included the technical advisement of the AntennaLab team, pa of the Signal and Communication Theory department. This technical advisement task consists on evaluating and monitoring the deployment of a wireless communication network which operates in the L9 subway facilities. As a result of this agreement and as a part of the advisory tasks this thesis has two objectives. The first objective is to characterize the radio-propagation by a comprehensive model. This model must be useful from a network deploying manager point of view. The second objective is study feasible ways to provide high and constant data rates to the ground-to-carriage link. The objectives are divided in several tasks. In order to provide the radio-propagation model mentioned above the general Electro Magnetic (EM) propagation theory in subway tunnels has to be revisited and summarized in order to get the knowledge which rules that propagation. Theoretical models and simulators of the propagation path losses in subway tunnels are neede to provide coverage information. Simultaneously to the EM general theory development a revision of Multiple-Input-Multiple- Output (MIMO) concepts must be performed in order to define descriptive magnitudes of MIMO performance in tunnels. This leads to connect the EM field theory in tunnels with MIMO system theory in a comprehensive level by new performance measure magnitudes. At the end an experimental validation of the theoretical models must be performed and semi- empirical models have to be compared with the theoretical models mentioned above. In the las four years two sections of the L9 subway line have been developed. These sections include th wireless communication which supports the automatic control train, the train status monitoring and the video surveillance networks. The last two years have been devoted to prepare the line services for public transport and begin the service. Therefore, the four years of advisory work has successfully finished with a complete development plan, a technical description of the possible solutions and evaluating process description which allows defining the viability of installed equipments.