What is a quarter wave ground plane antenna?
A common type of monopole antenna at these frequencies for mounting on masts or structures consists of a quarter-wave whip antenna with a ground plane consisting of 3 or 4 wires or rods a quarter-wave long radiating horizontally or diagonally from its base connected to the ground side of the feedline; this is called a …
How long is a quarter wave CB antenna?
The optimal antenna length for CB frequencies is 102” as this represents one-quarter of a wavelength.
How does a ground plane affect an antenna?
In the case of a 1/4-wave antenna, the ground plane acts as the counterpoise to form, in essence, a centered 1/2-wave dipole. Since this plane is the other half of the antenna, its size and proximity are essential. Often an antenna can appear smaller than its specified wavelength.
Does a half wave antenna need a ground plane?
Does a 1/2 wave antenna need a ground plane? Answer: No. It does not require a ground plane to work efficiently. In fact it is best to install the 1/2 wave antenna at least 8 inches from any nearby metal objects for better performance.
How many radials are in a quarter wave antenna?
Quarter Wave Ground Plane Antenna Calculator. Ahh, the good old quarter wave ground plane! This calculator can be used to design a Quarter Wave Ground Plane antenna, with radials. The radiating element is a quarter wave (λ/4) and the radials are 12% longer. There are usually four radials, three being a minimum, but you could use up to six.
What is a quarter wave antenna used for?
It provides good performance combined with an omnidirectional radiation pattern and simplicity of construction. The quarter wave vertical antenna is used at all frequency bands including LF, MF, HF, VHF and beyond. VHF and beyond.
What is the feed impedance of a quarter wavelength vertical antenna?
The feed impedance of a quarter wavelength vertical fed against a ground plane is 37Ω: against that of a dipole which is 73Ω. This can be an issue if the antenna needs to be fed with standard 50Ω coaxial feeder. To overcome this, the ground plane conductors can be bent downwards from the horizontal raise the feed impedance.
What is an antenna ground plane?
Using an antenna ground plane can enable a simulated ground to be made and allow the antenna to be mounted above ground. Ground mounted antennas are often very easy and convenient to use.