= A Directional antenna =

Short for Biquadratic

=== More Info Links ===
   1. http://trevormarshall.com/biquad.htm - biquad overview and theory (11dBi)
   1. http://martybugs.net/wireless/biquad/ - detailed biquad construction info (11dBi)
   1. http://martybugs.net/wireless/biquad/double.cgi - a double biquad (13dBi)