This paper focuses on the research of channel capacity of multiple-input multipleoutput
(MIMO) system with different transmitting angles in straight and curvy tunnels.Araytracing
technique is developed to calculate channel frequency responses for tunnels, and the
channel frequency response is further used to calculate corresponding channel capacity. The
channel capacities are calculated based on the realistic environment. The channel capacities
of MIMO long term evolution system using spatial and polar antenna arrays by different
transmitting angles are computed. Numerical results show that, The channel capacity for
transmitting angle at 15◦ is largest compared to the other angles in the tunnels. Moreover,
the channel capacity of polar array is better than that of spatial array both in the straight and
curvy tunnels. Besides, the channel capacity for the tunnels with traffic is larger than that
without traffic. Finally, it isworth noting that in these cases the presentwork provides not only
comparative information but also quantitative information on the performance reduction.
Wireless Personal Communications 79(2), p.941-951.