Robust phase-based positioning using massive MIMO with limited bandwidth

Abstract

This paper presents a phase-based positioning framework using a massive MIMO system. The phase-based distance estimates of MPCs together with other parameters are tracked with an EKF, the state dimension of which varies with the birth-death processes of paths. The RIMAX and the modeling of dense multipath components in the framework further enhance the quality of parameter tracking by providing an accurate initial state and the underlying noise covariance. The tracked MPCs are fed into a time-of-arrival self-calibration positioning algorithm for simultaneous trajectory and environment estimation. Throughout the positioning process, no prior knowledge of the surrounding environment and base station position is needed. The performance is demonstrated with the measurement of a 2D complex movement, which was performed in a sports hall with an antenna array with 128 ports as base station using a standard cellular bandwidth of 40 MHz. The positioning result shows that the mean deviation of the estimated user equipment trajectory from the ground truth is 13 cm. In summary, the proposed framework is a promising high-resolution radio-based positioning solution for current and next generation cellular systems.