Doppler-Enabled Single-Antenna Localization and Mapping Without Synchronization

TL;DR

This paper demonstrates that Doppler estimation enables accurate localization and mapping using a single-antenna user equipment in 5G/6G systems, eliminating the need for complex antenna arrays at the user side.

Contribution

It introduces a novel method leveraging Doppler and multipath components for single-antenna localization without synchronization, supported by theoretical analysis and simulations.

Findings

Localization accuracy improves with UE speed and saturates at a certain point.

The proposed method achieves near-optimal performance as indicated by Cramér-Rao bounds.

Single-antenna localization is feasible without additional hardware complexity.

Abstract

Radio localization is a key enabler for joint communication and sensing in the fifth/sixth generation (5G/6G) communication systems. With the help of multipath components (MPCs), localization and mapping tasks can be done with a single base station (BS) and single unsynchronized user equipment (UE) if both of them are equipped with an antenna array. However, the antenna array at the UE side increases the hardware and computational cost, preventing localization functionality. In this work, we show that with Doppler estimation and MPCs, localization and mapping tasks can be performed even with a single-antenna mobile UE. Furthermore, we show that the localization and mapping performance will improve and then saturate at a certain level with an increased UE speed. Both theoretical Cram\'er-Rao bound analysis and simulation results show the potential of localization under mobility and the effectiveness of the proposed localization algorithm.