5G NR indoor positioning by joint DL-TDoA and DL-AoD

The topic of indoor positioning of a user terminal is becoming increasingly significant in the context of mobile networks as accurate localization based on global navigation satellite systems (GNSS) is not possible inside buildings. The 5G New Radio (NR) networks based on the 3GPP have introduced several enhanced features to allow the accurate positioning of user terminals. By utilizing mmWave for the downlink positioning reference signals (DL-PRS) in a 3GPP Rel-16 5G NR system in Frequency Range 2 (FR2), we investigate the performance of a combined method consisting of Downlink Time Difference of Arrival (DL-TDoA) and Downlink Angle of Departure (DLAoD). TDoA is a widely used horizontal positioning technique that does not require tight synchronization between base stations and mobile stations. Moreover, Multiple antennas beamforming on base stations leads to high vertical positioning accuracy with

AoD. We use ray-tracing-based site-specific channel models to evaluate our joint positioning algorithm’s performance in an Indoor Factory (InF) scenario. The simulation results show submeter user localization error which is a significant improvement compared to applying the previous methods separately.