Jeg har ikke selv erfaring med en sådan løsning, men jeg fandt dette afsnit på internettet:
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3.7: Typical WLAN topology.
WLAN ranges can reach as high as 500 meters outdoors with no obstacles present. It is based on use of unlicensed Industrial, Scientific, and Medical (ISM) band, 2.4 to 2.5 MHz, which brings clear cost advantages to commercial WLAN deployments. On the downside a 2.4-MHz frequency is now also used by cordless telephones and Bluetooth devices and can potentially interfere with microwave ranges emission and vice versa.
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Den Wi-Fi dongle (USB-netkort) med højeste WiFi-Bånd er på 5 GHz:
http://www.edbpriser.dk/Product/Details.aspx?pid=700470De fleste "normale" netkort har en styrke på 2.4 GHz til 3.0 GHz
Det er lidt af en satsning om det ville virke.
Ellers kan vi snakke om reelle "access points":
http://www.edbpriser.dk/Search/Products.aspx?q=&qft=&s=&cpath=1-4-71&qt=Fql&nf=strmatrix3%3a^%22Wi-Fi+CERTIFIED+%C2%A40.0000000000%22%24[MultiValSep]%C2%A7price%3a[50%3b62795]%C2%A7specifictaxonomy%3a^%22Netv%C3%A6rk|4%2fAccess+point|71%22%24Her har et access point formentlig større sandsynlighed for at være relevant, men det svært at vurdere om hvilken en der kan nå 500 meter.