Extending Your Wireless Range with a Cantenna

By Tim Ahlers

Wireless is great and all, but why is it that the spot I want to sit with my laptop is always just out of range? Read on to discover the fun and flexibility of extending your wireless signal with a cantenna (can + antenna).

My initial motivation for building my cantenna: to be online while sitting at a picnic table at the street end park just a short distance from Pure Networks World Headquarters. Id heard about those Pringle can antennas that were supposed to focus your wireless signal, taking the energy usually going into an omni-directional antenna and focusing them into a directional beam. I did some research, found this site on the web, and decided to create a real cantenna, one that had been tested against a bunch of other cantennas. (It turns out those Pringles can antennas dont do very much to boost your signal.)

First I had to do some research on the router I use at work-- a D-Link DI-624 -- to figure out what kind of connector its antenna uses. I found this site to be particularly helpful. I ended up ordering a complete cable from this site, because they had a package specially made for constructing a cantenna -- the connectors on both sides were included, and they pre-soldered the correct-length wire on the antenna side.

Second, I had to find the proper can. Based on the performance results from the site I referenced earlier, I went looking for the Nalley Big Chunk Beef Stew can specifically, until I realized that Nalley made several soups and soup-like products in the same-sized can. I ended up with a chili can that was the perfect size.

Lastly, I had to assemble the whole thing. I used the web site's instructions to figure out how far from the bottom of the can to mount the antenna element. Then I used a nail to create a pilot hole, then used the biggest drill bit I had handy to make it larger. I ended up using a Dremel tool to expand the hole to the proper size. After that, it was just a matter of screwing the antenna element into the can, and connecting the other end of the antenna wire to the back of the router. Voila!

The only thing left to do was point it at the picnic table in the park.

How'd it work? I tested it out at that park down at the end of the street and it works great. From that location, I can see other networks from the office, but theyre all one or two signal strength bars. But my cantenna-boosted wireless network registers *five* bars on my laptop -- maximum signal strength.

But then I realized, why stop there? Why not try to actually get out on the water and still have a wireless connection? Stay tuned for test results from a boat on the lake... :)