MIMO Channel Spatial Correlation and Capacity in Tunnel Entrance Scenarios

Channel spatial characterization for tunnel entrance scenarios is an essential issue to ensure the sustained and stable mobile broadband communications of railway communication system. In this letter, a geometry-based channel model for multiple-input multiple-output channels in tunnel entrance scenarios is proposed. The closed-form expressions of channel spatial correlation and capacity are derived. The impacts of different scenarios and transceiver element spacings on channel spatial characteristics are thoroughly analyzed. Moreover, the measurement results are utilized to validate the proposed model and numerical results.