What is a helical antenna used for?

What is a helical antenna used for?

Helical broadcasting antennas Specialized normal-mode helical antennas are used as transmitting antennas for FM radio and television broadcasting stations on the VHF and UHF bands.

How do you calculate helical antenna?

Where S is the Spacing between helix turns, N number of turns, C is the speed of light and λ is the antenna wavelength. The antenna Gain = 32.08dB Pitch angle �� = 15.9° Height of antenna is known by formula H = N× ��, 2.2. 5 Where H = height of the antenna.

What is the bandwidth of the helical antenna?

The proposed strip-helical antenna has an impedance bandwidth of over 80% and an AR bandwidth of 56%, while the wire helical antenna has neither an impedance bandwidth nor an AR bandwidth with the same number of turns.

How is helical antenna different from other antenna?

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. These antennas operate in one of two modes: normal mode and axial mode.

Which mode of helical antenna is of practical use?

The axial mode is usually the most practical because it can achieve circular polarization over a wider bandwidth and it is more efficient. The normal mode: In this mode, the field radiated by the antenna is maximum in a plane normal to the helix axis and minimum along its axis.

What is the advantage of using helical antenna over straight wire 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 parameters of helical antenna?

The antenna geometry is described with the following parameters: circumference of helix C = πD , spacing p between the successive turns, diameter of helix D = 2a , pitch angle ψ = tan-1( p / πD ), number of turns N , total length of the antenna L = Np , total length of the wire L n = NL 0 where L 0 is the wire length …

How long is a 5.8 GHz antenna?

The normal 5.8 GHz antenna length is 12.9 mm.