A cantenna is a directional waveguide antenna for long-range Wi-Fi used to increase the range of (or snoop on) a wireless network. Although the original design was based on a Pringles potato chip can, a cantenna can be made from various cans/bottles. These include antennas on both the ground and antennas heightened by means of a pole. While cantennas are useful for extending a wireless local area network (WLAN), the tiny design makes them ideal for mobile applications such as wardriving. The design of the cantenna is so simple that it is often the first antenna WiFi experimenters learn to build.
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