H vs V polarization: Can't we all get along?

Your typical wifi box has vertical polarization. The notebook wifi
cards are horizontally polarized. This doesn't seem very well planned.

So wouldn't it make sense to have circular polarization, especially if
you are building antennas for stumbling purposes?

For a somewhat different question, some high power cards have two
antenna connectors. [SMC2532W-B] Does anyone know if this card polls
both antenna connections? What I am leading to is you could do your
stumbling with two different antennas, one H and one V, letting the
antenna choose on the fly.

On 17 Mar 2006 11:31:07 -0800, (E-Mail Removed) wrote:

>Your typical wifi box has vertical polarization. The notebook wifi
>cards are horizontally polarized. This doesn't seem very well planned.

Planning? Surely you jest. Actually, the typical PCMCIA antenna has
quite a bit of both vertical and horizontal polarization. If the
antenna was in a "clean" environment, free of outside influences and
reflectors, it might be an issue (such as in a point to point link),
but not with a typical notebook internal antenna or PCMCIA card.

The Effect of Electric Field Polarization on Indoor Propagation.
http://www.bell-labs.com/org/wireles...ub/icupc98.pdf
Conclusions show less than 2dB loss due to polarization mismatch.

>So wouldn't it make sense to have circular polarization, especially if
>you are building antennas for stumbling purposes?

No. The difference is negligible for most situations. Circular
polarization does make sense for point to point links and over water,
where reflections from the ground may cause cancellation problems. The
reflection changes sense (left hand becomes hight hand) thus
eliminating any odd numbered reflections. Circular polarization also
drastically reduces the effects of Rayleigh fading, but that has
little effect on Netstumbler results.

>For a somewhat different question, some high power cards have two
>antenna connectors. [SMC2532W-B] Does anyone know if this card polls
>both antenna connections? What I am leading to is you could do your
>stumbling with two different antennas, one H and one V, letting the
>antenna choose on the fly.

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558 (E-Mail Removed)
# http://802.11junk.com (E-Mail Removed)
# http://www.LearnByDestroying.com AE6KS

Stop calling me Shirley. ;-)

I was thinking more of netstumbling applications rather than strickly
indoors, thus the polarization should matter. I suspect vertical
polarization is best for drive-by applications since we know the WAPs
are vertically polarized.

BTW, I managed to find some info on that SMC card. Diversity in receive
only. The transmitter only comes out the connector near the LEDS. I ran
this card with a biquad a few times and suppose I must have picked the
right connector by luck since I never had it not work.


Jeff Liebermann wrote:
> On 17 Mar 2006 11:31:07 -0800, (E-Mail Removed) wrote:
>
> >Your typical wifi box has vertical polarization. The notebook wifi
> >cards are horizontally polarized. This doesn't seem very well planned.
>
> Planning? Surely you jest. Actually, the typical PCMCIA antenna has
> quite a bit of both vertical and horizontal polarization. If the
> antenna was in a "clean" environment, free of outside influences and
> reflectors, it might be an issue (such as in a point to point link),
> but not with a typical notebook internal antenna or PCMCIA card.
>
> The Effect of Electric Field Polarization on Indoor Propagation.
> http://www.bell-labs.com/org/wireles...ub/icupc98.pdf
> Conclusions show less than 2dB loss due to polarization mismatch.
>
> >So wouldn't it make sense to have circular polarization, especially if
> >you are building antennas for stumbling purposes?
>
> No. The difference is negligible for most situations. Circular
> polarization does make sense for point to point links and over water,
> where reflections from the ground may cause cancellation problems. The
> reflection changes sense (left hand becomes hight hand) thus
> eliminating any odd numbered reflections. Circular polarization also
> drastically reduces the effects of Rayleigh fading, but that has
> little effect on Netstumbler results.
>
> >For a somewhat different question, some high power cards have two
> >antenna connectors. [SMC2532W-B] Does anyone know if this card polls
> >both antenna connections? What I am leading to is you could do your
> >stumbling with two different antennas, one H and one V, letting the
> >antenna choose on the fly.
>
> --
> # Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
> # 831-336-2558 (E-Mail Removed)
> # http://802.11junk.com (E-Mail Removed)
> # http://www.LearnByDestroying.com AE6KS