Horizontal Polarized Omni
Horizontal Polarized Omnis are mystery for me 
. Anyone was seen open vertical polarized omni for wifi. Whit horizontal ones there is another story. Except slotted waveguides /these works great/ , but they are really big things.
Here is one idea for horizontal omni or “double helix antenna” :
http://hft.uni-duisburg-essen.de/amateurfunk/amateurfunk_en.shtml
Mast is used for reflector for for this one. Ant in the internet there is a lot of designs for spiral antenna. Difference here is that is used dual spirals. Coaxial line is hidden inside of the mast, and its look like that feeding point is on the bottom of the antenna.
One more link - there was calculator for this antenna on that treat : http://wireless.com.pt/forum/index.php?topic=15786.0 but now I cant find it.
Thanks to the rt_rex You can find calculator on this site : Omni Helix XLS
I hope that soon we can see some results and tests of this antenna.
Tags: coaxial line, double helix, helix antenna, mast, Omnidirectional, reflector, spiral antenna, wifi antenna
August 24th, 2007 at 12:28 am
Hi the Excel file you are talking about was made by me ,but the forum recently changed the looks and some attached file are no longer available.
I have made an english version of the file you can find it here:
[url=http://www.albufeira-villas.com/wifi/Omni_Helix_Calc_EN.xls]Omni Helix[/url]
I also updated the forum with the link to the file .
by the way the feed is @ the middle of the tube,not @ the bottom as mentioned
No one as build one yet to see if it works well under 2.4 ghz but we are almost done
August 31st, 2007 at 5:05 pm
Thanks for the link - I hope that soon we can see some test results.