Parabolic Antenna

Description
A parabolic antenna is an antenna that uses a parabolic reflector (a curved surface with the cross-sectional shape of a parabola) to direct the radio waves. The most common form is shaped like a dish, so it is generally called a dish antenna or a parabolic dish.

Advantages
The main advantage of a parabolic antenna is that it has high directivity. It functions similarly to a searchlight or flashlight reflector to direct the radio waves in a narrow beam, or receive radio waves from one particular direction only. Dish antennas have some of the highest gains, that is, they can produce the narrowest beam widths.

Application
1. In order to achieve narrow beam width, the parabolic reflector must be much larger than the wavelength of the radio waves used, so parabolic antennas are used at the high frequency part of the radio spectrum, like UHF and microwave (SHF) frequencies, at which the wavelengths are small enough that reflectors can be used.
2. Parabolic dishes are used as high-gain antennas for point-to-point communications, such as microwave relay links that carry telephone and television signals between nearby cities, wireless WAN/LAN links for data communications, satellite communications and spacecraft communication antennas. They are also used in radio telescopes.
3. The other wide use of parabolic antennas is for radar antennas, in which there is a need to transmit narrow beam of radio waves to locate objects like ships, airplanes and guided missiles.
4. With the arrival of home satellite television receivers, dish antennas have become common.

Principle
Today’s antenna designs are improved upon Hertz’s early work. A parabolic antenna is a unidirectional antenna since it transmits signals in only one direction. The parabolic dish of antenna is known as the reflector. The reflector creates a large surface area that the antenna uses to receive and transmit signals. The innermost part of the dish is the vertex, where the reflector gathers and strengthens signals it collects.

Jinchang Company has been engaged in parabolic antennas R&D, designing, manufacturing and selling for 28 years. Other main products include GPS/GLONASS/COMPASS/GSM/CDMA/GPRS/WIFI/DAB-DVB antennas, various combo antennas, connectors and interface cables.