A Joint TOA and DOA Acquisition and Tracking Approach for Positioning With LTE Signals

Abstract

A receiver structure is proposed to jointly estimate the time-of-arrival (TOA) and azimuth and elevation angles of direction-of-arrival (DOA) from received cellular long-term evolution (LTE) signals. In the proposed receiver, a matrix pencil (MP) algorithm is used in the acquisition stage to obtain a coarse estimate of the TOA and DOA. Then, a tracking loop is proposed to refine the estimates and jointly track the TOA and DOA changes. The performance of the acquisition and tracking stages are evaluated in the presence of noise and multipath. Simulation results are provided to validate the analytical results. The Cramér-Rao lower bounds (CRLBs) of the TOA and DOA estimates are derived to compare the performance of the proposed acquisition and tracking approaches with the best-case performance. It is shown that the proposed approach has lower complexity compared to the MP algorithm. Finally, experimental results are provided with real LTE signals, showing a reduction of 93%, 57%, and 31% in the standard deviation of TOA, azimuth, and elevation angles' estimation errors, respectively, using the proposed receiver compared to the MP algorithm.