Experimental Evaluation of Round-Trip ToF-based Localization in the 60 GHz Band

Millimeter wave (mmWave) communication has emerged as a key technology for achieving high data throughput and low latency in 5G networks. Thanks to the large channel bandwidths in the mmWave spectrum (e.g. 2.16 GHz in the 57-66 GHz band), mmWave technology allows precise and accurate time of flight (ToF) measurements, hence supporting precise and accurate positioning. In this paper, an experimental evaluation of ToF-based localization in the 60 GHz band is presented. We implemented the two-way ranging (TWR) protocol between a mobile node and multiple anchor nodes. The implementation is carried out on an own software-defined radio (SDR) baseband platform, combined with commercial 60 GHz chipsets. Tests were performed indoors in a laboratory environment. The results of our evaluation show that a positioning error of less than 5 cm can be obtained.

I. Introduction

The fifth generation (5G) of mobile communication networks are anticipated to provide a massive leap when compared to the existing networks in terms of system capacity, data throughputs, end-to-end latency, seamless coverage (via dense small cells), number of connected devices, network energy efficiency, etc. [1], [2]. Besides, highly accurate device positioning and location-aware communication are envisioned. The positioning accuracy is expected to be in the order of a meter or even sub-meter [3], [4]. Such a high-performance positioning is essential for new emerging applications and location-based services, including safety-critical applications, augmented reality [5], assisted living [6], healthcare and emergency services [4], etc. In addition, positioning information can be used as support for channel estimation or to perform beamforming by steering transmission towards a user (with known position), therefore reducing the beam search time.