Recent results of high-resolution wireless indoor positioning based on IEEE 802.11ac

This contribution addresses the problem of highly resolving the propagation time difference of arrival (TDOA) associated with signals in multipath communication channels for wireless indoor positioning. The Unitary Matrix Pencil (UMP) algorithm is enhanced and applied in a new way to estimate the propagation time delays from the estimated space channel frequency response (S-CFR) using MIMO-OFDM systems. The performance of using wideband orthogonal multicarrier signals and multiple antennas for wireless positioning are presented. A non-iterative least square (LS) estimator is also presented to estimate the mobile unit (MU) coordinates based on the TDOA observations. Experimental results using the emerging IEEE 802.11ac standard show that accuracy in the range of two cm can be achieved for two-dimensional (2-D) wireless indoor positioning.