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Old July 27th 03, 04:31 PM
Richard Clark
 
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On Sun, 27 Jul 2003 16:01:55 +0100, "Rob" wrote:

Not being an RF engineer, I need to know the dimensions of the reflector for
a double bi-quad antenna for a wireless lan link (two wire bowties placed in
front a flat plate reflector - here is a quad bi-quad:
http://www.frars.org.uk/cgi-bin/rend...62&goback=1064).

2 x "double sided PCB 260mm by 230mm"
This is how I see it (I may be wrong), any wires that have no sheild will
act as a radiator, so if the length is a wavelength or wavelength divided by
2,4,8 etc (ie speed of light in air/frequency, 300,000,000ms/2,440,000,000hz
= 0.123meters), then the wave is not disturbed and continues along its path.
The biquad is a piece of wire 244mm(2 wavelengths) long folded into 2
squares, so I guess you have 8 radiators.
So to connect 2 biquads or patch panels together the wire below would have
to be 123mm long and connect to the coax in the centre.
Therefore a double biquad would be 123 x 244mm, but I need someone to
confirm this.
The radiator part I think is OK, its the reflector size

"double sided PCB 260mm by 230mm"
and raditor spacing

"spaced 14mm from the ground plane"
I am not sure about.

Cheers

Rob