Joint estimation of time delays and directions of arrival using proper set of antenna elements of a high-order antenna array

Abstract

In this work, we investigate the accuracy and complexity deviation between using all or selected antenna elements of a massive MIMO array for source localization. In addition, we address the problem of highly resolving the propagation time delay, and the angles of arrival (azimuth and elevation) associated with signals in multipath communication channels for many location-based services and three-dimensional (3D) beamforming. The 3D unitary matrix pencil (3D UMP) algorithm is enhanced and applied in a new way to evaluate these parameters simultaneously from the estimated space channel frequency response (S-CFR) using wideband orthogonal multicarrier signals and uniform rectangular array (URA). Furthermore, the 2D UMP is enhanced to estimate the unknown parameters of wideband signals impinging on 8 different array configurations that are structured as combinations of uniform linear arrays (ULAs). It is not necessary to use all antenna elements of a high-order antenna array for source localization. Due to the dependency on mobile unit location, the phase uncertainties and the deviation of received signal strength between array elements, using the proper set of antenna elements can provide a comparable accuracy and a considerable reduction in the computational complexity of the localization algorithm. The computational complexity is further reduced by exploiting real computation and similar eigen-structure property, and using a priori information of wireless positioning. The IEEE 802.11ac system parameters are used in our experiments.