Re: wifi-plus antennas, was VT problem

David Josephson wrote:
> It's too bad that the antenna people in this business so often make 
> their case with so much smoke and noise that the average user can't tell 
> what's real and what's fluff. Wifi-plus is nothing more or less than 
> stacked, radome-enclosed, more or less circularly polarized, array 
> antennas such as have been used for FM broadcast for 40 years or more. 
> There is some benefit to this, particularly in urban areas, but no 
> antenna is magic, and no antenna is going to make pine needles and 
> leaves disappear. Any antenna produces "gain" solely by directing more 
> of the power you feed it in one direction and less in others; a 
> circularly polarized antenna can actually result in lower signal 
> strength because part of the signal is radiated in a polarization that 
> isn't received by a given, optimal, receiving antenna. Over a 
> point-to-point link you're not going to do any better than well matched 
> parabolic antennas aligned to the same polarization.

Well-said.  Agreed, even.   (Though if you match the polarizaion of any 
two antennas, you'll not see the effect you state.)  That, and you'll 
need to restrict "do better" to "have more link margin", since the 
higher directivity may actually lead to more OBSS interference, since 
the other STAs won't see a high-enough signal level to set CCA.

But I digress.

I was 'holding back' not wanting to provoke a vendor war.

There is a *lot* of BS in the wireless world.
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