Multi-Dimensional Bounds on Time-of-Arrival Statistics in Random Scattering Channels

Bounds on Gaussian and hyperbolic time-of-arrival (ToA) probability density functions (pdfs) in multi-path mobile environments are derived. The bounds are expressed as functions of the coverage distance D between a base station (BS) and a user equipment (UE), and the propagation time ratio tau (n) = tau/tau (0) where tau is the general time delay and tau (0) is the nominal time delay between the BS and the UE via the direct line-of-sight path. Detailed discussions on the variation of the ToA pdfs in 1-D and 3-D are given which are useful for system modelling in mobile environments.