Capacity of Multiconnectivity mmWave Systems with Dynamic Blockage and Directional Antennas

Abstract

<p>The challenges of millimeter-wave (mmWave) radio propagation in dense crowded environments require dynamic re-associations between the available access points (APs) to reduce the chances of losing the line-of-sight path. However, the antenna beamsearching functionality in the mmWave systems may introduce significant delays in the course of AP re-association. In this paper, we analyze user performance in dense urban mmWave deployments that are susceptible to blockage by the dynamically moving crowd. Our approach relies on the ergodic capacity as the key parameter of interest. We conduct a detailed evaluation with respect to the impact of various system parameters on the ergodic capacity, such as AP density and height, blocker density and speed, number of antenna array elements, array switching time, degree of multiconnectivity, and employed connectivity strategies. Particularly, we demonstrate that dual connectivity delivers the desired performance out of all possible degrees of multiconnectivity, and there is an optimal density of mmWave APs that maximizes the capacity of cell-edge users. We also show that the use of low complexity 'reactive' multiconnectivity design, where the beamtracking is only performed when the currently active connection is lost, together with the utilization of iterative beamsearching algorithms, does not significantly deteriorate the ergodic capacity.</p>