Antenna Basics

Directional Antennas

Directional antennas as the name implies refers to signal coverage in a specified direction. Unlike omnidirectional antennas, directionals must be aimed in the direction of the signal transmitter or receiver which can be for example a router or WiFi hotspot. When it comes to aiming the antenna the user must be right on the signal for the best strength and quality. The way to ensure your aim is best is to know the width of the reception cone in which the antenna has. A good way to start without seeing actual lab data or knowing the specs is to judge by the dBi (decibel isotropic) rating. The higher the dBi rating the narrower the reception cone and knowing these data points you can then begin to narrow down the right antenna for you. As a rule of thumb to remember, high dBi rating = further distance covered but not area.

Omnidirectional Antennas

Omni directional antennas are most commonly are used to create hot spots by transmitting a signal over a large area in all directions or receiving signals in all directions when the transmit location is unknown or close by. Omni WiFi antennas do not need to be pointed since their radiation cone is 360 degrees, working in all directions. Each specific antenna has a gain rating or dBi (decibel isotropic) number which coincides with the performance. The higher the dBi rating the larger the area the signal covers. Keeping that in mind and thinking about what your specific needs are you can begin to narrow down what antenna is best for you.

 Reference Chart: 

 

Antenna	Type	Best use	Signal use	Location	Max Range
2.5 dBi	Omni directional	USB adapters	Receive	Indoors	300ft
5 dBi	Omni directional	USB adapters	Receive	Indoors	500ft
7dBi	Omni directional	Routers/Adapters	Receive/transmit	Indoors	800ft
8dbi	Omni directional	Routers/Adapters	Receive/transmit	Outdoors	1500ft
9dbi	Omni directional	Routers/Adapters	Receive/transmit	Indoors	1200ft
9dBi Panel	Directional	Routers/Adapters	Receive/transmit	Indoors	.25 miles
11dBi	Omni directional	Routers/Adapters	Receive/transmit	Outdoors	.25 miles
14dbi	Omni directional	Routers/Adapters	Receive/transmit	Outdoors	.4 miles
Yagi Cantenna Tripod 14dBi	Directional	Routers/Adapters	Receive/transmit	Indoors	2 miles
Yagi Cantenna Mount 14dBi	Directional	Routers/Adapters	Receive/transmit	Outdoors	3 miles
Panel Tripod 14dBi	Directional	Routers/Adapters	Receive/transmit	Indoors	2 miles
Panel Mount 14dBi	Directional	Routers/Adapters	Receive/transmit	Outdoors	4 miles
Dish Grid 19dBi	Directional	Routers/Adapters	Receive/transmit	Outdoors	5 miles
Parbolic Grid 24 dBi	Directional	Routers/Adapters	Receive/transmit	Outdoors	8 miles

 

NOTE: All range data is under ideal circumstance but will perform in the ball park. Maximum range is achieved through the use of powerful receivers and transmitters as well as a clear line of sight between them.