One-Reflection Path Assisted Fingerprint Localization Method with Single Base Station under 6G Indoor Environment.

Precise positioning is critical in autonomous driving, indoor navigation, and intelligent logistics. With the development of mobile communication technology, indoor base stations (BSs) have been utilized and installed to match indoor signal coverage better. Thus for indoor positioning, cellular signals have emerged as a new option. Ranging through the time of arrival (TOA) is achieved by capturing cellular signals as a signal of opportunity for localization. This approach can only estimate the user equipment (UE) to BS distance when there is just one BS and cannot obtain the two-dimensional (2D) coordinates. In this paper, we combine the fingerprint positioning approach with the signal parameters acquired via cellular signal of opportunity. TOA and one-reflection path are employed as fingerprint features, and 2D localization with a single BS is achieved. A complete signal processing flow is constructed, and the ray tracing method is performed to generate the channel parameters to evaluate the proposed positioning algorithm's performance and match the practical application as closely as feasible. Using the 100GHz carrier frequency that conforms to the sixth generation (6G) communication for simulation, the mean positioning error is 0.312m when the fingerprint interval is 0.5m. This method provides a feasible solution for 6G indoor positioning scenarios.