Linksys sells a "range extender" which is essentially a LNA and a power
amplifier in a box that neatly mounts underneath a WAP11 (access point) and
has the appropriate jumper cables. They run around $70-80.
Are you sure that increasing power will actually solve the problem?
1) Increasing power on the access point helps the AP to remote link, but
does nothing for the mobile to AP link, where it's the mobile unit power
that determines stuff. Yes, a lower noise receiver in the AP would help,
but, by and large, they're all using the same part, and all about the same NF.
2) If the problem is an intefering signal, then amplifiers may or may not
actually help, depending on the relative ranges, etc. Say your neighbor
has just installed a WAP11 and he's only 10 feet from your mobile, while
your WAP 11 is 50 feet away. He's got a 5:1 range advantage (that's 25:1
power... 14 dB!). No legal or practical amplifier's going to help (RF
safety starts to be an issue if you're looking at going 14-15 dB over the
existing 100 mW.. )
Similar effects can be noted from the decidely non-uniform field strength
in an actual installation.
3) I'd look into better antennas... they help both directions of the
path. If your access point is towards one side of the house, a relatively
low gain antenna with a hemispherical pattern, or one that has a bit of
vertical directivity (i.e. squirts the power out in a horizontal fan) might
help a lot. 10 dBi of gain makes a HUGE difference, and, of course, you're
never going to get 10 dB of improvement in the receiver.. the NF is
probably down in the 1-2 dB range now...) Try improvising a corner
reflector for an experiment.. aluminum foil is cheap.
4) for some folks, adding an access point on a different frequency in a
different place in the house helps. There are also wireless repeaters, but
they have 1/2 the throughput (they are essentially digipeaters)... it's a
trade between much stronger signal and half the data rate, so you don't
burnup datarate doing retries.
5) Do check your channels... 1, 6, and 11 are the mutually exclusive channels.
6) Going to a 5 GHz system might be a better solution... worse propagation
through walls and such, but much, much less interference from cordless
phones, alarm systems, microwave ovens, wireless video links, other 802.11b
WiFi networks, oh yeah, and that ham down the street running a kilowatt for
Moonbounce.. 2.4 GHz ISM band is very, very cluttered, and getting worse.
At 01:12 PM 7/15/2003 -0500, Chuck Sudds wrote:
>Having problems with my wireless internet access and have advised to
>purchase a 2.4 GHz Bi-Directional Amplifier. Does anyone have any ideas
>where to get one of these items at a reasonable price?? Thanks, in advance.
>
>Chuck K?TVD
>
>
>_______________________________________________
>
>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
>any questions and ask for Sherman, W2FLA.
>
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