What is so interesting about reflector antenna? It’s generally used to reflect waves from the spectrum range of electromagnetic radiation and is very useful for long-distance satellite communications.
Applications of reflector antennas were first realized during World War II when the soldiers in the sea used the radar system to communicate with other ships.
This article will discuss the basic types of reflector antenna, their structures, operating principle, and possible viable applications. Make sure to stick with us till the end!
What is A Reflector Antenna?
According to the antenna theory, a reflector antenna reflects electromagnetic waves. This type of antenna contains one or more reflecting surface that helps them to receive or transmit signals through matter and space.
As per configuration, there are various shapes of a reflector antenna, single curve or paraboloid reflector antenna, and so on.
Why is Reflector Antenna Important?
An antenna is a major source of wireless communication. From the satellite sourcing to your internet connection, everything is connected to the antenna. With every design, antennae are capable of more gain, aperture efficiency, and faster communication.
At every transmission of signals, an effective power loss distorts the transmitted signal, reducing the antenna efficiency. With the elegant design of the reflector antenna, the efficiency has increased to 75% with little power consumption as possible.
Basics Of Reflector Antenna
This type of primary antenna is also considered highly directional and transmits or receives signals from long-distance communications.
These reflector antennae’s bandwidth range is from 1 Hz to 1 kHz. The proposal of a horn reflector antenna was first proposed by the scientist Hertz in 1888 which later created a revolution in radar communication across the sea.
Types Of Reflector Antenna
Basically, there are two types of reflector antenna with similar antenna arrays. The characterization of antennas is given below:
- Active Element Reflector Antenna
It’s also known as a feed antenna, where the driven element is an active component, such as a resistor, that creates an electrical connection with the transmitter or the receiver.
- Parasitic Element Reflector Antenna
This antenna type consists of both active and passive elements, creating a parasitic effect during signal transmission and reception.
On top of that, many other reflector shapes are there that one should have a vast knowledge of. They are as follows:
- Rod
- Plane
- Corner
- Cylindrical
- Spherical
- Parabolic
Structure Of Reflector Antenna
As we mentioned earlier, an antenna reflector consists of one or more reflecting surfaces that highlight electromagnetic wave reflection. Due to its radiation pattern, it’s a popular face in radar communication.
There are two core components of the reflector antenna that sums up its whole structure. They are:
- Radiating System
- Reflector
Operation Of Reflector Antenna
In most cases, the practical implementation of a parasitic reflector antenna is more popular. The active element inside the antenna provides the excitation for the signal transmission.
On the other hand, the passive element is used as a reflecting surface which re-radiates the energy that the active element emits.
In simpler terms, the feeder acts as an active element, whereas the reflector works as a passive element in a reflector antenna.
Radiation Pattern Of Reflector Antenna
If we’re considering the x-axis and y-axis as the direction of propagation, then the radiation pattern of reflector antenna has a major lobe around the propagations. A radiation pattern is the graphical representation of the transmission of EM waves.
The x-axis is denoted by the dimension of the antenna and the y-axis accounts for the respective gain of the antenna. Altogether, we see that the reflector antenna has a major lobe around the axes and the side lobes in between.
Advantages Of Reflector Antenna
The followings are the advantages of a reflector antenna:
- High Antenna Gains
These antennas have high antenna gains, reflecting the output of the wavelength it radiates. A larger wavelength leads to less distortion in the signals.
- High Directivity
Apart from reflector antenna producing high gain, they can provide high levels of directivity. With a narrow range of beamwidth, one can establish a higher range of gain, hence high directivity.
The relations are directly proportional to each parameter. This can be a significant benefit in applications where power must only be directed over a small area.
- High Aperture Efficiency
Aperture efficiency, similar to antenna efficiency, is the ratio of the radiating area to the aperture area of the antenna. Reflector antenna, such as parabolic reflectors, have high aperture efficiency, providing less power consumption due to transmission.
Disadvantages Of Reflector Antenna
The antenna theory also suggests that there are certain disadvantages of reflector antennae that antenna designers also need to have in mind. They are as follows:
- Requires External Reflector and Drive Element
The parabolic-shaped reflector is only a part of the antenna. Additionally, it will have an external reflector and drive element to establish the prime focus of the signal transmission.
As a result, this building cost rises, and the drive element results in additional power loss.
- Cost
As mentioned above, the cost of building such a type of antenna will be very costly. The parts purchased will be expensive if one accounts for a wider antenna – beam and antenna – spectrum.
- Size
The antenna dimensions are large, which will take up a lot of space during the installation process. Additionally, handling such a huge antenna might also be problematic.
Application Of Reflector Antenna
As mentioned earlier, the main application of reflector antenna is in the area of satellite communication and radar systems.
Additionally, because of their capability to reflect electromagnetic waves, they are also used for point-to-point communications, radio astronomy, deep-space telemetry, and broadcasting channels in television and radio communications.
Aside from these, other uses for reflector antennas include weather radar, radio astronomy, and spacecraft systems.
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Frequently Asked Questions
What is the simplest version of reflector antenna?
The simplest version of a reflector antenna contains a plane reflector. One big disadvantage of this type of antenna is that the energy direction is not perfectly perpendicular to the reflecting surface.
What is the function of the reflector in the satellite?
There are many shapes of reflectors added to man-made satellite communication. These reflectors are mostly curved, which enables them to propagate the received signals at one single point and make them stronger.
What are the general antenna types and the reflector antenna category?
There are three basic types of antenna-directional, semi-directional, and omnidirectional. Based on the function of the reflector antennae, they’re categorized as directional antennae.
Conclusion
The antenna properties are the real reason why naval engineering is fond of such reflector antenna. Apart from radar communication, antenna geometries also benefit TV signal broadcasting.
While talking about the drawback, the antenna measurement makes it hard to carry around during the installation. Next time someone asks about the science of reflector antenna, mention this article to gather vast knowledge about it.