hi All.
Spidey : Thanks. We would be glad to get to the bottom this issue. Thanks
for your help.
Ratsalad :
Now, that is a question ....... it’s almost impossible to answer.
No, that’s not just me taking the easy way out either - let me
give a lengthy explanation, since this is quite a common question.
Radio signals, particularly of the frequencies used in 802.11b/g
transmission, travel in what is know as "line of sight" paths. This
means, that, instead of traveling through things like walls, they
bounce around them. Basically this means that in order to travel
your 10 meters through 2 walls, the signal may have to actually
travel 30 meters, bounce off 6 walls and pass through 2 windows -
All of which will reduce the signal strength dramatically..
Alternatively, it could be a simple path that just causes the signal
to travel 10 meters and pass through 2 windows, in which case, it
is almost certain that a connection will be made and decent
speeds achieved (there may also be no path at all, so connection
would then be impossible). Unfortunately, I do not know your site,
where you are putting the router etc, so I cannot predict range.
Range is further limited by local interference - are there other
things nearby that can cause radio interference - things like other
routers, fluorescent lights etc.?
Generally, there are ways to improve range for a given
environment, such as increasing power output or putting an Arial
with more gain on the router. Unfortunately, the output power is
limited by law, to around 120 mW , if I recall correctly, so the
only option that you have to increase range if you do not have
control on the external factors (interference etc) or on the internal
factors (walls, positioning of router) would be to change the
antenna. Be warned though, that this also has its disadvantages,
since all antennae do is to "focus" the signal, and don't generate
any additional power, so if you increase the signal strength in one
direction, you are loosing out in another direction - of cause, this
may not be a problem. Also remember, that data comms is a 2
direction communication, so whatever signal path you are dealing
with, you will need both the router and the PC's card to have
enough power/receive sensitivity to make
the connection
Another point to remember: there are 2 sorts of people that are
involved in getting the router to you: Engineers and Sales people.
Because they know about the above info, and the many other
factors that are involved, I doubt that you will
find an engineer that will be prepared to give you any range figures
other than open air ranges - that is the theoretical max. Range.
Sales people, on the other hand, are quite likely to take that figure,
and advertise it as a sales point. This is not limited to Telkom or our
organization, but is a worldwide trend. There is also trend to not
acknowledge that in some situations, wireless communications
will just not work.
This is, of cause, a summery of the story of Wireless range, but it
should be enough to give you an idea.
The best that I could do is comment on the open air range - the
range when there are no walls in the way, and also tell you that I
regularly get in excess of 10 meters in my office. I would suggest
that you find a friend with a laptop that has a built-in Wireless
card, and test your situation first, before you spend the money on
the cards.
Hope that this helps.
Regards
2C Telecoms.
