Indoor Tracking: Theory, Methods, and Technologies

TLDR

Indoor tracking has become a rapidly evolving field, driven by the need for reliable, high‑definition real‑time positioning in environments where people spend most of their time, yet no legacy solution has emerged due to the inherent challenges of indoor environments. This survey aims to review indoor wireless tracking of mobile nodes from a signal‑processing perspective, outlining its theory, key tools, and promising technologies while highlighting emerging research directions. The authors examine the theoretical foundations, core signal‑processing tools, and state‑of‑the‑art technologies that enable indoor tracking of mobile nodes.

Abstract

In the last decade, the research on and the technology for outdoor tracking have seen an explosion of advances. It is expected that in the near future, we will witness similar trends for indoor scenarios where people spend more than 70% of their lives. The rationale for this is that there is a need for reliable and high-definition real-time tracking systems that have the ability to operate in indoor environments, thus complementing those based on satellite technologies, such as the Global Positioning System (GPS). The indoor environments are very challenging, and as a result, a large variety of technologies have been proposed for coping with them, but no legacy solution has emerged. This paper presents a survey on indoor wireless tracking of mobile nodes from a signal processing perspective. It can be argued that the indoor tracking problem is more challenging than the problem on indoor localization. The reason is simple: From a set of measurements, one has to estimate not one location but a series of correlated locations of a mobile node. The paper illustrates the theory, the main tools, and the most promising technologies for indoor tracking. New directions of research are also discussed.