wireless paths crossing

Hi,

I am installing some antennas on a couple of hangars 300 feet apart. As
suggested by several people, I went up on the roof and checked to lans with
netstumbler. I saw a few, but the signals were low. However, one thing
that concerned me was that I noticed 4 hangars down a parabolic antenna
pointing to another parabolic antenna about 1/4 mile away. I check and
these antennas are for another WiFi (2.4 Ghz) net. The worse thing is that
the 2 hangars I am connecting will result in an "X" being formed between my
2 antennas and their 2 antennas, as shown below.

Their Ant A My Antenna A
\ /
\ /
\ /
\ /
/\
/ \
/ \
My Antenna B Their Antenna B


Will this prevent my connection from working?

Thanks,

Jerry

Jerry Kurata wrote:
> Hi,
>
> I am installing some antennas on a couple of hangars 300 feet apart. As
> suggested by several people, I went up on the roof and checked to lans with
> netstumbler. I saw a few, but the signals were low. However, one thing
> that concerned me was that I noticed 4 hangars down a parabolic antenna
> pointing to another parabolic antenna about 1/4 mile away. I check and
> these antennas are for another WiFi (2.4 Ghz) net. The worse thing is that
> the 2 hangars I am connecting will result in an "X" being formed between my
> 2 antennas and their 2 antennas, as shown below.
>
> Their Ant A My Antenna A
> \ /
> \ /
> \ /
> \ /
> /\
> / \
> / \
> My Antenna B Their Antenna B
>
>
> Will this prevent my connection from working?

No, not if you do it half way responsibly. Choose the channel farthest
away from them. In fact, if they are using 6 ask them if they'd mind to
choose either 1 or 11 and you'll take the other so there would be as
little chance of interference as possible. You can also go to horizontal
polarization if they are on vertical to further reduce interference.

On Fri, 5 Nov 2004 19:32:38 -0800, "Jerry Kurata" <(E-Mail Removed)>
wrote:

>Hi,
>
>I am installing some antennas on a couple of hangars 300 feet apart. As
>suggested by several people, I went up on the roof and checked to lans with
>netstumbler. I saw a few, but the signals were low. However, one thing
>that concerned me was that I noticed 4 hangars down a parabolic antenna
>pointing to another parabolic antenna about 1/4 mile away. I check and
>these antennas are for another WiFi (2.4 Ghz) net. The worse thing is that
>the 2 hangars I am connecting will result in an "X" being formed between my
>2 antennas and their 2 antennas, as shown below.
>
>Their Ant A My Antenna A
> \ /
> \ /
> \ /
> \ /
> /\
> / \
> / \
>My Antenna B Their Antenna B
>
>
>Will this prevent my connection from working?

It should be no problem at all if:
1. They are on a different channel or frequency.
2. You also use parabolic dish antennas to minimize side lobes.
3. There are no reflections for nearby buildings. Think billiards.

Crossing paths does not "mix" the signals in mid air, so there's no
interaction. The narrow beamwidth of the dish antennas will keep the
radios from seeing each other. Putting them on different
non-overlapping channels (1,6,11) will prevent interference even if
the antennas do see each other. Reflections from building can screw
up the works.

At 300ft, it's more likely that you'll have an overwhelmingly good RF
signal level and therefore will not be very susceptible to
interference. I can't say the same for the other user, who may
receive more interference from you than they create due to the
differences in range. One thing for sure... you're committed to using
directional antennas (panel, patch, or dish) to avoid interference.



--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831.336.2558 voice http://www.LearnByDestroying.com
# (E-Mail Removed)
# 831.421.6491 digital_pager (E-Mail Removed) AE6KS

: Will this prevent my connection from working?

Simply - it's gonna be working. But don't forget to
set a different channel.


m.


--
Marcin Lukasik
Milea Wireless Communications, http://milea.pl
phone/fax/mobile: (++48) 13 44 800 70, 13 44 811 48, 509 390 490

,,the only difference between men and boys is the price of their toys''