As you have already found this website you probably already know what a
WLAN is, however for those new to this technology keep reading!
A WLAN is simply a Wireless Local Area Network, just as many
computers are linked together to form a LAN using cables, it is now
possible to create these connections using Radio signals.
The technolgy is far from new, although now it is becoming more
mainstream, which means anyone can create or connect to a computer
network easily.
Provided that the equipment is compatible and has been set-up
correctly, then it is just a question of being within range of
the radio signal.
The radio signal used to send and recieve information between two or
more computers is much more sensitive to LOS or Line Of Sight issues
than say a traditional radio or TV signal because WI-FI or
Wireless-Fidelity Technology used in WLAN equipment operates at a much
higher frequency.
What this means in practice is that unless the two antennas connecting
the networks together have clear space between them it might not be
possible for them to 'connect'. Over short distances this isn't
normally a problem, however over larger distances it can create big
problems.
One of the best methods of creating a clear LOS between the two
antennas is firstly selecting the correct type and power of antenna and
secondly mounting the antennas high enough to clear virtually all
obstacles in their path.
This isn't always possible, mainly due to problems mounting the
antennas high enough and so this problem can be overcome by
having smaller and less powerful antennas operating over shorter
distances which usually means that the antennas can be mounted much
lower. The only drawback is that extra 'repeater' sites are needed, the
same signal can now be sent a large distance using a number of small
'hops'.
As you can see this is a much more viable alternative to physically
connecting computers together using cable and the cost is very
reasonable.