Robert,

While I don't have specific experience with Skycross antennas, the 
underlying idea is well established -- two different radiation patterns 
from elements in the same area, i.e.a scheme that creates pattern 
diversity.  This is possible and commercial versions are being driven 
the need for MIMO in the small devices like mobile phone. s

For MIMO you need multiple "independent" antennas. One approach is to 
use polarization, vertical and horizontal, but that only gives you 2x2 
MIMO.  Polarization is what Orthogon did (now the Moto P2P-600).  To get 
more independent antennas, the simple approach is to use space antenna 
elements apart (ideally by a half wavelength or more).  Of course that 
doesn't work well in a handset, especially at 700 MHz where a half 
wavelength is >8 inches.

But if you can get two different radiation patterns from structures in 
the same physical space, that also works for MIMO.  For an intuitive 
sense of why, consider:  the secondary and tertiary signals a MIMO 
system is trying to decode are arriving from different directions 
(because they were created by reflections).  If the you can get two or 
more different antenna patterns by feeding different parts of a complex 
structure in the same small area, those feeds will behave differently 
for the different signals, primary, secondary, tertiary, etc.  That 
gives you the "independent" signals you need for the MIMO computations 
to work.

Of course, this is theory.  There's usually some major steps from theory 
to the real world.  :)  Sorry I have no real world experience here.

- Brough Turner


Robert West wrote:
> Saw this on TowerTalk, had me scratching my head.    Anyone familiar with
> these antennas or is this the next WiFi+  B.S.?
>
> http://www.rfdesignline.com/howto/showArticle.jhtml;jsessionid=F1SQHL23DOWTNQE1GHPCKHWATMY32JVN?articleID=222001586
>
> Robert West
> Just Micro Digital Services Inc
> 740-335-7020
>   


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