Distributed Two-Way Localization Bounds for 5G mmWave Systems

Recently, localization for 5G millimeter-wave communication systems has been shown to provide high-accuracy performance, with error being in the order of tens of centimeters. However, most of the literature assumes a high level of synchronization, which is not always the case practically. To address this matter, we investigate a distributed two-way localization protocol (DLP) that relieves the need for tight timing synchronization. We derive the position and orientation bounds, when localization is initiated and carried out by the base station. Our simulation results show that the performance of DLP is identical to that of the synchronized one-way localization. We thus conclude that the considered 5G localization is limited by the estimation of the angles rather than the delay. The results also imply that orientation estimation is more challenging than position estimation.