Omnidirectional and Directional antennas - what's the difference?

There are two types of antennas, directional and Omni-directional.
 
Omni directional antennas provide a 360° donut shaped radiation pattern to provide the widest possible signal coverage in indoor and outdoor wireless applications. An analogy for the radiation pattern would be how an un-shaded incandescent light bulb illuminates a room. Types of Omni directional antennas include "rubber duck" antennas often found on access points and routers, Omni antennas found outdoors, and antenna arrays used on cellular towers.

Directional antennas, as the name implies, focus the wireless signal in a specific direction resulting in a limited coverage area. An analogy for the radiation pattern would be how a vehicle head light illuminates the road. Types of Directional antennas include Yagi, Parabolic grid, patch and panel antennas.

Directional antennas are primarily used for point to point communications including long range connectivity applications between two facilities or devices.
 
The range of a directional antenna depends on the gain (dBi) of the antenna, Line of Sight (LOS) conditions, antenna frequency; transmit power of the connected radio, weather conditions and the presence and severity of EMI and RFI.

Directional antennas are used in commercial, industrial and military applications typically outdoors where harsh weather conditions are present.

L-com manufactures directional antennas with harsh environments in mind. We offer UV-stable, UL flame rated radome covered directional antennas as well as non-radome stainless steel directional antennas designed to stand up to the extremes. Other features include rugged mast mounting kits designed to stand up to high winds and vibration and drain holes in the radome versions for moisture control.