Influence of antenna configuration on mm-wave MIMO performance in a subway-like tunnel

摘要

This study investigates the channel performance of a 28 GHz multiple-input–multiple-output (MIMO) system in a subway tunnel, using ray-tracing-based simulations and experimental measurements in a realistic tunnel environment. The transmitter (Tx) array was deployed at three positions, i.e. in the centre of the tunnel, close to the sidewalls and under the ceiling. The performance was significantly better in the centre and sidewall positions. Good agreement is obtained between simulation and measurement results. Furthermore, it is inferred that the MIMO channel capacity for the Tx–receiver distance of 60 m is higher than that of 15 m. The angular spread calculated for the 60 m case is also larger than that of the 15 m case.