It's more true to say that both signals need to be amplified, whether that happens in 
the antennas (directional versus omni), at each end using a TX amplifier, or at one 
end with a TX/RX amplifier.  In the case where a PoP site will serve a wide area, it 
may be best to use a TX/RX amp coupled to a hi-gain omni antenna at the PoP site, 
which allows the use of a standard OEM antenna at each node.  As the distance between 
node and PoP site increases, the node's chance of connecting are improved by replacing 
the OEM antenna with a hi-gain omni or directional antenna mounted in a good location, 
and/or by amplifying its own TX signal.

Amateur radio operators will equate this (well, I will, anyway) to VHF/UHF 
communications (up to about 1.2GHz, that I'm aware of), where a repeater station (PoP 
site) is located high up, like on a mountain or tall building, with a premium antenna 
and both a high power transmitter and very sensitive receiver, and used by lower 
powered portable and mobile radios (nodes) that could not otherwise communicate with 
each other because of the distance.  The higher powered radios (nodes with TX 
amplifiers) will be able to communicate from further away than others, and a gain 
antenna (node with a beam or dish) will also increase the distance.


-----Original Message-----
From: Jason Lewis 
Sent: Friday, July 05, 2002 11:17
To: [EMAIL PROTECTED]
Subject: RE: Wireless LAN question


>
> given that "the other wlan device" is equipped with a directional
> antenna, too..
>

Nope.  You can amp your signal and use a directional antenna and the other
end can be using a low power antenna.  It is a common belief that both
ends need to use the same antennas or be amplified.  This is not true.  I
can compensate for your weak signal with my stronger one.

Sometimes the polarity of the antenna doesn't match, which is easy to
correct by rotating the antenna.

Do not rely on the antenna for security.





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