Projects

RADIO PLANNING IN TUNNELS

PROJECT DESCRIPTION

This project is conducted in cooperation with IFERCAT. IFERCAT is responsible of the construction of the new L9 underground metro in Barcelona and its metropolitan area. The L9 spans over 42 km and is characterized by the depth of its tunnels, by the singular construction procedure of the two-level cylindrical tunnel and by incorporating advanced control systems that will allow the operation of Automated Train Control (ATC). The need to use higher frequecies, larger bandwidths and high reliability  requires carefull radioplanning to guarantee service and interoperability of all radiosystems. The AntennaLab at UPC is developing a prediction tool that starts with an accurate Electromagnetic Modeling of the propagation in the tunnel to obtain channel characteristics to assess and predict the performance of wireless communication systems. Of special interest are the train-to-ground communication systems.

DESCRIPTION OF THE ACTIVITIES

ELECTROMAGNETIC MODELLING

One of the key issues of the project is the accurate modelling of the electromagnetic propagation in the tunnel. The use of high frequency bands as 2.45 GHz and 5.8 GHz for some of the train-to-ground communication systems requires specific simulation tools that can efficiently simulate the pathloss atenuation at this higher frequencies.  The EM analyisis is based on the Iterative Spectral Propagation technique, and allows to compute the field distribution inside the tunnel for a given antenna position in the tunnel.

VALIDATION MEASUREMENTS

To validate the EM prediction tool is necessary to perform validation measurements  in real scenarios. As the  L9 tunnels are under construction, specific measurement campaings are conducted in L2.The measurements are performed at night when the metro is not in operation and the objective is to obtain data to validate the EM prediction tool and to adjust physical parameters of the tunnel such as wall rugosity and reflectivity. Also specific noise measurement when the metro is in operation have been conducted to  characterize the noise level at the frequency bands of interest.