“Omnidirectional” is generic term for an antenna that radiates equally well in all directions. There are several antennas that are considered omnidirectional.
1/2 Wavelength Vertical
Most folks lump all vertical omnidirectional antennas into the same category and call them “Ground Planes”. A ground plane antenna is actually an antenna similar to the vertical dipole.It’s important to understand the difference – especially if you’re looking to invest in a certain type. Whether you’re after antennas or Mobile Broadband deals, misinterpretations usually end badly. Shown in figure 1, you can see the hollow tubing is now instead brought out at a 45 degree angle (and split into 3 sections) out from where it is on the vertical dipole. These rods are usually called “radials”. This type of antenna is really not a very high gain antenna. Continue reading