Rainfall Effect on the Performance of Millimeter-Wave MIMO Systems

This paper considers the rainfall effect on the capacities and achievable rates of millimeter-wave (mmW) multiple-input multiple-output (MIMO) systems. We first develop a new channel model for point-to-point mmW MIMO systems to characterize the rainfall effect. This rain propagation model is derived based on stochastic properties of signal propagation in a general random scattering medium. Under this model, we evaluate the channel capacity of the mmW MIMO system at various rain rates and show that rainfall does not always have a negative impact on the system performance, provided that accurate instantaneous channel state information (CSI) is available at both the transmitter and receiver. We also show that a transmit strategy of statistical water-filling (SWF) allows the mmW MIMO system to have near-optimal performance.