Around-the-Corner or Through-the-Wall? Classification of Non-Line-of-Sight Conditions

It is well known that location accuracy is low in non-line-of-sight (NLOS) scenarios. Several techniques have been proposed to mitigate ranging errors to improve location accuracy. These techniques play an important role in accurate localization for many applications which target safety and productivity in harsh industrial environments. In some cases, these mitigation techniques target specific NLOS scenarios, therefore such scenarios have to identified before mitigation can be applied. In this paper, we study identification of two types of NLOS scenarios that are common indoors: Through-the-Wall (TTW) and Around-the-Corner (ATC). We conduct a measurement campaign in various indoor TTW and ATC scenarios, and show that these two types of NLOS scenarios can be differentiated with high accuracy using channel statistics from ultra-wideband radios.