“…Since an approximate model for the environment is sufficient for this feasibility study, we chose not to incorporate more advanced features that are already described in literature, e.g., three-dimensional (3-D) propagation [10]; [11]; diffraction effects; and detailed material descriptions of walls [12], windows [13], and furniture [14]. Instead, we chose to incorporate the movement of the receiver in our ray tracer, including Doppler shift [15], and changing ray parameters with time. To this end, we do not only calculate all the relevant ray parameters, but also their derivatives with respect to the movement of the receiver.…”