You can boost the range of your wifi router/card by using an external antenna. The simplest option for you would be to construct a couple of antennas out of cans. The whole thing will cost you a couple of bucks and will be more than enough to cover 500 meters (I used such antennas for 3-km long links, and it worked like a charm). Hit Google with 'cantenna' to get more info on the subjet. If you decide to go this way, make sure your wifi card and router are equipped with detachable antennas so that you can hook an external one.
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You can boost the range of your wifi router/card by using an external antenna. The simplest option for you would be to construct a couple of antennas out of cans. The whole thing will cost you a couple of bucks and will be more than enough to cover 500 meters (I used such antennas for 3-km long links, and it worked like a charm). Hit Google with 'cantenna' to get more info on the subjet. If you decide to go this way, make sure your wifi card and router are equipped with detachable antennas so that you can hook an external one.