A new spatial path persistency model for TOA-based indoor geolocation

Analysis of the persistency and birth/death of multipath components of the channel impulse response is essential for performance evaluation of indoor geolocation algorithms using indirect paths for ranging. The use of indirect paths via multipath diversity is particularly important for situations where the direct path gets blocked. In this letter, we propose a statistical model for the spatial behavior of the persistency of multipath components as a mobile moves inside a building. Based on empirical data from a measurement calibrated ray tracing algorithm we show that the persistency in a typical building is modeled by log-logistic distribution rather than commonly assumed exponential distribution and path birth can be modeled as a Poisson distribution.