The single most important thing you can do to extend the range of your 802.11 system is to install an external antenna with some good gain and directional or omni-directional qualities. WiFi is simply a radio, which is used for computer. You can think of your antenna as the “speaker system” of your WiFi card. Get a bigger antenna; your WiFi will go a lot further. However, don't install a speaker on your wifi system or your range will be horrible!Directional Antennas
Directional antennas are used for Point-to-Point or sometimes for Multi-Point systems depending on the setup. If you are trying to go from one location (say for instance your router), to another location, this is the type of antenna we recommend. Directional antennas are Backfires ,Yagi,Panel and dish type antennas.

Omni-Directional
This is the common “Base” antenna used for Point-to-Multi-Point or can be an omni-directional antenna for your car. An Omni-Directional antenna would serve as your main antenna to distribute the signal to other computers or devices (such as wireless printers, PDAs, etc) in your workgroup. You can use 2 Omni-Directional antennas for a point to point system, but this is usually not recommended because there is no real point to distributing your signal all over the place when you only want to going from point A to point B. Please refer to Directional antennas above. Typical Omni-Directional WiFi antennas consist of Vertical Omni , ceeling domes , Rubber duck , Small desktops and mobile vertical antennas.