Cantenna
Homemade directional waveguide antenna from a metal can.
A cantenna is a directional waveguide antenna built at home from an open-ended metal can, with the name combining "can" and "antenna." It is commonly used to extend the range or help discover Wi-Fi networks.
The cylindrical body can be made from metal-coated paperboard. While a Pringles potato chips can is sometimes used, its diameter is too small to meaningfully boost a 2.4 GHz signal, though it is roughly the right size for 5 GHz. Other cans or tubes of suitable diameter can work, and some designs include a pole mount to raise the antenna higher. At 2.4 GHz, signal loss can occur if the cable connecting the cantenna to the Wi-Fi circuitry is too long; a more efficient design minimizes this length or connects the cantenna directly to the circuitry.
Cantennas are typically used to extend a wireless local area network (WLAN). Their small size makes them practical for mobile uses like wardriving. They can also improve cell phone range, reception, and reduce noise. A cantenna can serve as a feed horn for a satellite dish; at 5.5 GHz, its dimensions align almost perfectly with standard TV satellite dishes, creating a low-cost, high-gain antenna often used in wireless community networks for long-distance Wi-Fi links. They may also be used with other RF devices, such as wireless security cameras.
- Frequency 2 4 ghz
- Losses can occur if the cable from the cantenna to the Wi-Fi circuitry is too long
- Frequency 5 ghz
- Pringles can is about the right size for 5 GHz
- Frequency 5 5 ghz
- Dimensions are almost perfect for a standard TV satellite dish feed horn
Lore & Background
The cantenna is constructed from the cylinder portion of a metal can, which may consist of metal-coated paperboard. Although some designs use a Pringles potato chips can, that tube is too narrow to increase the 2.4 GHz signal by a useful amount, though at 5 GHz it would be about the right size. Various cans or tubes of appropriate diameter can be used. Some designs include a pole mount to elevate the cantenna. At 2.4 GHz, losses can occur if the cable from the cantenna to the Wi-Fi circuitry is too long; a more efficient cantenna can be made by minimizing this length or connecting the cantenna directly to the Wi-Fi circuitry.
Reader's Guide
Cantennas are typically used for extending a wireless local area network (WLAN). Their tiny design makes them ideal for mobile applications such as wardriving. They can also be used to increase cell phone range, improve reception, and decrease noise. A cantenna can be used as a satellite dish feed horn; the 5.5 GHz cantenna dimensions are almost perfect for a standard TV satellite dish, resulting in a low-cost high-quality high-gain antenna. Such setups are widely used in wireless community networks for long-distance Wi-Fi links. Cantennas may also be used with other RF devices such as wireless security cameras.
Did You Know?
- The name 'cantenna' is a portmanteau blending the words 'can' and 'antenna'.
- At 5.5 GHz, cantenna dimensions are almost perfect for use as a feed horn for a standard TV satellite dish.
Frequently Asked Questions
What is a cantenna?
A cantenna is a homemade directional antenna built from a simple open-ended metal can, with the name blending the words "can" and "antenna." It operates as a basic waveguide that focuses radio signals into a directional beam.
How does a cantenna actually work?
The cylindrical metal body channels incoming radio waves through the tube like a waveguide, preventing them from spreading behind the can. The open end then radiates the concentrated signal outward in a focused pattern, effectively extending range in one direction.
Why is a Pringles can not ideal for 2.4 GHz Wi-Fi?
The diameter of a standard Pringles can is too small to meaningfully boost a 2.4 GHz signal. That said, its dimensions happen to line up well with 5 GHz frequencies, making it a more suitable choice for that band.
What can I use instead of a Pringles can?
Any metal tube or can with a diameter matched to your target frequency will serve as the cantenna body. Some builders also add a pole mount to raise the antenna higher and improve line-of-sight range.
What are the main limitations of a cantenna?
At 2.4 GHz, running a cable that is too long between the can and the Wi-Fi circuitry can introduce noticeable signal loss. The design is also strictly directional, so it only amplifies signals arriving from the direction the open end is facing.
More in Antenna Types 1-24
Spotted an error? Know more?
Reader corrections go straight into our review queue. Suggest an edit · How this site is sourced