Propagation modeling in subway tunnel using FDTD

The next generation mobile access network system design needs more precise characterisation of the radio channel and and needs sophisticated propagation models because of the decreasing cell sizes and of higher data rates. Especially planning coverage in tunnels and indoor spaces causes design problems without these models. The FDTD based model is able to characterise the above scenarios and using this a costly measurement effort can be reduced using simulation methods. In this article nearly circular subway tunnel is modeled in absence and presence of vehicle. The model can be applied for determine the field strength distribution on a cut plane of the tunnel with leaky cable excitation.