Pursuance of mm-Level Accuracy: Ranging and Positioning in mmWave Systems

This paper aims at investigating the feasibility of ranging and positioning in millimeter (mm)-level accuracy by adopting millimeter-wave (mmWave) and three-dimensional massive antenna arrays. The agent to be localized is equipped with massive uniform rectangular array (URA) and multiple anchors are considered to pursue a higher accuracy, where a far-field environment is assumed for phased massive URA. By considering both a static scenario where the agent with an unknown coordinate is stationary and a dynamic scenario where the agent is moving, the fundamental limits of time-based ranging and positioning are derived by Cramer-Rao bound in a multipath model with and without apriori channel knowledge associated with mmWave transmission and massive URA. The relationship between the fundamental bound of range estimation and that of position estimation is theoretically clarified and the lower bound of position dilution of precision is derived. By investigating both models, the effect of the agent's movement to ranging and positioning accuracy is observed. Numerical results show that the proposed localization network achieves a precise mm-level accuracy for ranging and positioning.