The Rician K-factor has been extensively used to characterize indoor and outdoor wireless propagation channels based on experimental and analytical models. In this paper, the K-factor statistics are derived analytically and experimentally validated for LOS and NLOS scenarios. Receiver operating characteristics (ROC) are formulated based on the derived detection statistics such that an optimal decision threshold can be selected to better enhance LOS/NLOS detection accuracy compared to usual methods. The proposed approach is shown to have a greater LOS/NLOS discrimination accuracy than other state-of-the-art approaches. Furthermore, there is evidence that a second metric can be obtained which characterizes the current environment and provides a confidence value, which can be used to inform further decisions.

Mechanical antennas have garnered interest as a potential method of transmitting extremely low frequency (ELF) to very low frequency (VLF) radiation in a manner which possesses a high efficiency of radiation and a low form factor. In this paper, we investigate these claims by solving for the exact field solutions from one particular example, a rotational-oscillating charged thin spherical shell. The field solutions allow analysis of the radiation pattern, radiation efficiency, and spectral output as a function of several geometric and kinematic quantities of the sphere. The results indicate that high efficiency with a low formfactor appears to be plausible, assuming the required mechanical conditions for the motion can be achieved.