Wideband Directional Radio Propagation Channel Analysis Inside an Arched Tunnel

To analyze the radio propagation channel inside a tunnel, a wideband directional measurement campaign was managed inside an arched tunnel which was constructed to be used for a highway. Using a wideband channel sounder equipped with a cylindrical dual polarized array at the receiver (Rx), the spatio-temporal characteristics of the received propagation paths could be estimated by means of a super-resolution estimation algorithm. The dominant scatterers are classified into 5 classes based on the structure of the tunnel as follows: ceiling, light-frames, walls, sidewalk or ground. The power contribution and cross polarization ratio for different Rx positions along the tunnel are compared