Indoor Radio Map Construction via Ray Tracing With RGB-D Sensor-Based 3D Reconstruction: Concept and Experiments in WLAN Systems

This paper proposes an RGB-D sensor-aided ray-tracing simulation framework for indoor radio map construction that models indoor information, such as walls and obstacles, as a set of cuboids. Radio maps can accelerate indoor wireless systems, including resource optimization and fingerprint-based localization. We can construct an accurate radio map using a ray-tracing algorithm with precise indoor structures and obstacles information. However, it is challenging to acquire this indoor information because manual observations of these are expensive. To mitigate this critical drawback, we propose utilizing three-dimensional information obtained from RGB-D images for ray-tracing simulation. The proposed method semi-automatically models indoor information as cuboids from three-dimensional information with RGB-D images. The proposed method then feeds these cuboids into a ray-tracing simulation. Indoor experiments using wireless LANs over 5180 and 2452 MHz clarified that the proposed method accurately constructs the radio map.