Antisolar point Antisolar point The antisolar point is the abstract point on the celestial sphere directly opposite of the Sun from an observer's perspective. This means that the antisolar point lies above the horizon when the Sun is below it, and vice versa. On a sunny day, the antisolar point can be easily found; it is located within the shadow of the observer's head. Like the zenith and nadir, the antisolar point is not fixed in three-dimensional space, but is defined relative to the observer. Each observer has their own antisolar point, which moves along with them as they change position. The
Point-to-multipoint communication wireless data communications for Internet or voice over IP via radio or microwave frequencies in the gigahertz range. Point to multipoint is the most popular approach for wireless communications that have a large number of nodes, end destinations or end users. Point to Multipoint generally assumes there is a central base station to which remote "subscriber units" or customer premises equipment (CPE) (a term that was originally used in the wired telephone industry) are connected over the wireless medium. Connections between the "base station" and "subscriber units" can be either line of sight or, for lower-frequency radio systems, non-line-of-sight where