Caracterização de canal rádio móvel em túnel urbano na faixa de 700 MHZ

Abstract

Currently, users of mobile broadband communications have become accustomed to accessing services remotely, anywhere and anytime. This only increases the concern of mobile operators to provide services with higher transmission rates and better coverage in all regions every day. A particularity of urban areas is the coverage of vehicular tunnels. The characterization of signal propagation in vehicle tunnels is necessary to assist planning engineers in optimizing coverage. The subject of the propagation of electromagnetic waves in tunnels with circular and rectangular cross sections has been addressed in several researches around the world that analyzed the characterization of the modes of propagation and coverage using experimental data and numerical modeling. There are, however, few studies carried out in Brazil, considering the frequency bands of 700 MHz. This work presents results of measurement campaigns in the Grota Funda tunnel in Rio de Janeiro at frequencies of 700 MHz. The data were collected by a mobile unit traveling at low speed along the tunnel. The dependence of the loss of the path with the distance traveled inside the tunnel and the dispersion parameters of the channel were obtained. It was found that the loss of propagation inside the tunnel is similar to the loss in free space, both in the sighted and non-sighted sections. The Average Delay was of the order of 113 nanoseconds and the Scattering of Delays RMS of the order of 60 nanoseconds. The RMS Delay Scattering values statistics were also calculated and presented.