Fine-Resolution Ranging Scheme Based on Signal Strength in Indoor Hallway With Rough-Surface Slab Waveguide

The received signal strength (RSS) is widely used in range-based localization because of its practical advantages, such as low cost and low complexity. For accurate ranging based on the RSS in indoor environments, well-defined propagation models (PMs) that consider the distortion of the RSS due to abrupt obstructions are required. This article proposes an exponential PM for indoor hallways whose structures can be modeled as a slab waveguide. This waveguide-shaped structure has two main power loss mechanisms: wave penetration and scattering. These loss mechanisms are quantified as exponential coefficients according to the law of conservation of energy. The surface-scattering theory and the multimode waveguide concept are utilized for the quantification of scattering and penetration, respectively. The proposed model is verified through actual site measurements using the vector network analyzer (VNA)-based channel-sounding system at IEEE 802.11ax frequency bands. The estimated range obtained from the measured data indicates that the proposed model leads to the ranging estimation performance that could not be achieved with existing sounding-based indoor channel models.