What are monopole and dipole antennas?

In essence, the difference between a monopole and dipole antenna, is that a dipole antenna uses an additionally radiator to generate a synthetic ground plane between the symmetric radiator elements, where a monopole antenna requires a physical ground plane. Dipoles tend to be more common.

Why do we use monopole antennas while having dipole antennas?

The monopole is often used as a resonant antenna; the rod functions as an open resonator for radio waves, oscillating with standing waves of voltage and current along its length. The load impedance of the quarter-wave monopole is half that of the dipole antenna or 37.5 Ohms.

What is the purpose of dipole antenna?

Dipole antennas are used in many areas, both on their own and as part of more complicated antennas where they can form the main radiating element. They are used in many forms of radio system from two way radio communications links, to broadcasting broadcast reception, general radio reception and very many more areas.

Where is monopole antenna used?

Applications – Cellular and cordless telephones, walkie-talkies, CB radios, etc. As Ground Plane Radius R increases, the gain maxima shifts towards lower resonance frequency. Gain and radiation pattern of a monopole antenna on small ground plane (< λ) are similar to that of dipole antenna.

What is the gain of monopole antenna?

The vertical dipole—or its electromagnetic equivalent, the monopole—could be considered one of the best antennas for LMR applications. It is omnidirectional (in azimuth) and, if it is a half-wavelength long, has a gain of 1.64 (or G = 2.15 dBi) in the horizontal plane.

Does a dipole antenna need a ground plane?

Answer: No. The 1/2 wave antenna (also called a dipole antenna) is built of two 1/4 wave elements that interact with one another to launch the electro-magnetic wave. It does not require a ground plane to work efficiently.

Why is it called dipole antenna?

A dipole antenna (also known as a doublet or dipole aerial) is defined as a type of RF (Radio Frequency) antenna, consisting of two conductive elements such as rods or wires. The dipole is any one of the varieties of antenna that produce a radiation pattern approximating that of an elementary electric dipole.

What is the polarization of monopole antenna?

The monopole antenna has only vertical polarization.

Does a dipole need to be grounded?

A dipole is a very basic antenna structure consisting of two straight collinear wires as depicted in Figure 1. Note also from Figure 2 that, a dipole does not require a “ground” to work.

What is the difference between a monopole and dipole antenna?

For a monopole antenna, the reference plane of the transmission line connection, outer conductor of a coaxial cable, is the ground plane of the monopole. Both monopole and dipole antennas exhibit similar radiation patterns and performance, except that monopole antennas are not symmetric vertically.

How do you calculate the length of a dipole?

Enter the desired operating frequency in megahertz to get a good starting length for a dipole in both feet and meters. The formula for calculating the approximate length of a dipole is: Dipole length in feet: 468 / frequency in MHz. Dipole length in meters: 143 / frequency in MHz. These are only approximate values.

What is the formula for the length of a dipole?

The formula to calculate the (approximate) overall physical length of a dipole is: Length (meters) = 142.58 / frequency (MHz) Length (feet) = 468 / frequency (MHz) The length of wire given by the formula is cut in half to make both sides of the dipole.