IntroductionThe BiQuad antenna is fairly easy to build and provides reliable gain and it has very forgiving design. You can make quite a big margin of error in the construction and still get 10-11dBi gain. Hence here is the Double BiQuad Antenna and BiQuad Antenna calculators for handmade antenna based on average data.
However I highly recommend to follow my instructions, which are based on computer antenna simulation software 4nec2, to maximize performance. Here is listed currently available instructions, simulated with computer software, for handmade 13-14dBi Double BiQuad external antenna.
Note: The dBi scale is logarithmic in base 10, where +3 dBi is a doubling in gain! An increase in gain of +1 dBi is equivalent to an increase of 26% and +2 dBi is equivalent to an increase of 60%. This means that the increase in +1dBi is a big deal.
Double BiQuad Antenna Calculator
BiQuad Antenna Calculator
Building the antennaI will not show you picture after the picture how to drill the hole in center of reflector. How to use ruler. How to do proper soldering. What kits to use and etc. There are plenty of tutorials for these steps: http://www.ziva-vatra.com/index.php?aid=16&id=SGFyZHdhcmU=, http://martybugs.net/wireless/biquad/ or http://martybugs.net/wireless/biquad/double.cgi
(Note: all calculations in links are for 2.4 GHz WiFi antenna. Use calculator calculated data and measurements for your antenna.)
(Note: Pictures below not to scale)
Before you start to bend the wire, make it straight as you can.
|Mine wire bending technique in the crossing sections.|
Note: You must leave a ~1.5 mm gap between the element wires cross overs and solders.
Guidance and recommendations
|N-connector in the center of reflector. Maintain correct reflector’s dimensions.|
|Maintain correct spacing between the element and the reflector!|
|Finished. Lying on the belly.|
|This antenna should get the best performance at horizontal polarization. |
Note: The antenna is horizontally polarized then reflector is held vertically.
Last updated on 14 Jul 2014