What are advantages of helical antenna?
Benefits or advantages of Helical Antenna ➨It can be used for broadband applications due to wider bandwidth. ➨It can be used at HF/VHF frequencies for transmission and reception. ➨It offers higher directivity. ➨It is very robust in construction.
What are the features of helical antenna?
Salient features of helical antenna
- Helical antenna is a simple antenna for circular polarisation.
- It is used in VHF and UHF bands.
- It is most popularly used in axial mode.
- In normal mode, beam width and efficiency are small.
- It is a wide band antenna in axial mode.
What is the importance of helical antenna explain the construction and operation of helical antenna with neat sketch?
Helical antenna or helix antenna is the antenna in which the conducting wire is wound in helical shape and connected to the ground plate with a feeder line. It is the simplest antenna, which provides circularly polarized waves. It is used in extra-terrestrial communications in which satellite relays etc., are involved.
How helical antenna is different from other antennas?
Helical antennas are usually mounted over a ground plane and the feedline is connected between the bottom of the helix and the ground plane. Helix Antennas usually support wide bandwidths compared to other types of antennas.
Why helical antennas are significantly used in satellite communication?
In addition to circular polarization, monofilar helical antennas offer the advantage of high gain in axial direction over a wide range of frequencies which makes them suitable for applications in broadband satellite communications.
How helical antenna is different from other antenna?
Helix Antennas usually support wide bandwidths compared to other types of antennas. To the casual observer, they appear as one or more “springs” or helixes mounted against a flat reflecting screen. These antennas emit and respond to electromagnetic fields with circular polarization.
How do helical antennas work?
Who invented helical antenna?
2. Monofilar helical antennas. The helical antenna was invented by Kraus in 1946 whose work provided semi-empirical design formulas for input impedance, bandwidth, main beam shape, gain and axial ratio based on a large number of measurements and the antenna array theory.
Why a helical antenna is used for satellite tracking?
A helical antenna is used for satellite tracking because of its circular polarization.
Which kind of polarization is provided by helical antennas?
circular polarization
The helical antenna is used for satellite communication due to its high directivity and circular polarization of the transmitted EM waves.
What are the applications of helical antenna?
The helical antenna is used for following applications. • It is used for transmission and reception of VHF signals through ionosphere. • It is used for satellite and radiometry applications. • It is possible to establish communication between moon and earth using it. ➨It is simple in design.
What are the disadvantages of a helical antenna?
Following are the disadvantages of Helical Antenna: ➨It is large in size. This requires more space for installation. ➨For higher number of turns its efficiency decreases. The maximum efficiency of about 80% can be achieved with the use of 3 to 4 turns. ➨It is higher in cost.
What are the advantages of a circular polarised antenna?
➨As it uses circular polarised pattern, it is acceptable by both horizontal and vertical polarised antenna types. ➨It can be used for broadband applications due to wider bandwidth.
How does the helix of an antenna affect antenna gain?
The number of turns in the helix determines how directional the antenna is: more turns improves the gain in the direction of its axis at both ends (or at 1 end when a ground plate is used), at a cost of gain in the other directions.