wow yagi-uda antenna can be used now in wifi.
That would be correct. Radio waves are radio waves, give them an appropriate antenna for the magic.
http://www.gigaparts.com/store.php?action=profile&sku=NW0054WiFi Yagi Antenna
This 15 dBi Wireless Yagi Antenna extends your range to lengths you never thought possible!
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Have you tried driving around your neighborhood to do security assessments for your neighbors, but can't seem to find any access points? Use this antenna and find dozens of networks you never knew existed!
16 Elements and 15 dBi Gain Increases WiFi Signals 32 Times Over a Standard Dipole Antenna