One of the basic functions of the transmitting antenna is to radiate the energy from the feeder to the surrounding space. The basic function is to radiate most of the energy in the desired direction. The vertically placed half-wave symmetrical vibrator has a flattened "bagel" shaped three-dimensional pattern. Although the three-dimensional pattern is strong, but the drawing is difficult, the plane pattern is used to describe the directionality of the antenna in a given plane.
A number of symmetrical vibrators form the ability to control the radiation, produce a "flat bagel", and concentrate the signal further in the horizontal direction.
It is also possible to use the reflector to control the radiant energy to the unilateral direction, and the planar reflector is placed on one side of the array to form the fan-shaped area covering the antenna. The following horizontal plane diagram illustrates the effect of the reflective surface - the reflector reflects the power to the unilateral direction and increases the gain.
The use of parabolic reflectors, but also make the antenna radiation, like the optical searchlight as the energy to a small solid angle, so as to obtain a high gain. It goes without saying that the parabolic antenna consists of two basic elements: a parabolic reflector and a radiation source placed on parabolic focal points.
Related Industry Knowledge