Overview

Devices based on the 802.11a/b/g wireless standard are typically designed to operate in an omnidirectional fashion. That is, it transmits and receives equally in all directions. By using the correct antenna, a signal can be focused in a single direction, which allows for more distance between the two endpoints, while maintaining signal quality. Yagi antennas are used to do this, but typically cost at least $100 (USD). Using the same priciples of these antennas, more cost effective antennas can be made from households items.

Pringles Can

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Our design is based on an article on the O'Reilly Network. We had to make some design changes to deal with parts that we had available at the local hardware store. The washers are only 3/4 in. in outer diameter, not the full 1 inch.

Supply List - Pringles Style (USD)

Part	Cost	Quantity	Subtotal	Notes
N-connector	$3.71	X 1	= $3.71	Source: Lafayette Electronic Supply
Nuts	$0.05	X 2	= $0.10
Washers	$0.10	X 5	= $0.50	only 3/4" in outer diameter, not the full 1"
Alum. Tube	$2.00	X 1	= $2.00
Thread	$0.90	X 1	= $0.90
Wire	$0.10	X 1	= $0.10	insulated, needed to be removed
Pringles	$0.80	X 2	= $1.60	Two lids are needed
Total			= $8.91

Cookie Can

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Our design is based on a design from Seattle Wireless.

Lessons learned:

The hot glue doesn't stick to the metal cans well, some tape can fix this.

Supply List - Cookie Can Style (USD)

Part	Cost	Quantity	Subtotal	Notes
N-connector	$3.71	X 1	= $3.71	Source: Lafayette Electronic Supply
Wire	$0.10	X 1	= $0.10	insulated, needed to be removed
Can	$4.00	X 1	= $4.00
Total			= $7.81

Results

In order to use the cantenna, you need a cable to connect it to the external antenna connection on your wireless device (not all devices have these). We got our pigtail adaptors (MC style) from Invictus Networks.

In using the two types of cantenna, both seem to perform well in situations when a directional antenna is useful. The cookie can style seems to be slightly better in our testing.