3-D Parameterized Multipath Channel Estimation for Massive MIMO–OFDM Systems

Abstract

In this article, we propose a three-dimensional (3-D) joint angle and delay estimation approach for massive multiple-input and multiple-output orthogonal frequency division multiplexing systems on the basis of the channel state information of a single base station, which is equipped with multiple antennas. By modeling the propagation channel by a finite number of multipath rays, we present a joint azimuth-angle, elevation-angle, and path delay estimation algorithm, in which a new version of subcarrier smoothing is developed for full-rank correlation matrix construction. The new algorithm offers closed-form parameter estimates and is applicable to arbitrary array configurations. The Cramér–Rao bound for the considered problem is derived as well. Simulation results with a typical outdoor millimeter-wave setup are finally presented to verify the efficacy of the proposed approach.