Wireless Home Networking - Index of

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Part II: Making Plans
To achieve optimum signal coverage, the best place to install an AP is near
the center of your home. Think about where you will place the AP when you
make your buying decision. All APs can sit on a shelf or table, but some APs
can also be mounted to a wall or ceiling. When making your AP selection,
ensure that it can be installed where it works best for the configuration of
your house as well as stays out of reach of your little ones or curious pets.
The position of the access point is critical because your entire signal footprint
emanates from the AP in a known way, centered from the AP’s antennas.
Sometimes, not enough consideration is given to the positioning of the access
point because it so often works well out of the box, just sitting on a table.
Other people install the AP wrong in the first place. For example, probably
one of the worst manufacturing decisions was to put mounting brackets on
access points. People get the impression that you should then — duh —
mount them on the wall. That’s great except for the fact that, depending on
the antenna, you may just kill most of your throughput. You see, when an
antenna is flush up against a wall, as is typical in a wall-mount situation, the
signals of the antenna reflect off the wall back at the antenna, causing interference
and driving down throughput precipitously. Yech. (But you see, customers
want a wall-mount bracket, so product managers at wireless LAN
companies decided that they had to give it to them.) The best mounting is
six or more inches off the wall.
The vertical positioning of the mounting point is important as well. Generally,
you have more interference lower to the ground. If you did a cross section of
your house in 1-foot intervals, when you get higher and higher, you would see
less on your map. Thus, signals from an access point located on a shelf low to
the ground will find more to run into than the ones that are mounted higher.
Although this may sound like common sense, consider that most DSL and
cable modems are installed by technicians who are used to installing phone
and cable TV lines. How many of these are generally located 5 feet off the
floor? They’re not; they tend to be along the floorboards and low to the ground
or in the basement. It’s not surprising that a combined DSL access point router
would be plugged in low to the ground, too.
See where we’re going with this? You don’t care where your cable modem is,
but you should care where your AP is located. And, if you have an integrated
product, you’re probably tempted to swap out the cable modem for the cable
modem access point. Simply moving that unit higher almost always does a
world of good.
Moving an AP out of the line of sight of microwaves, cordless phones, refrigerators,
and other devices is a good idea, too. Mounting the AP in the laundry
room off the kitchen doesn’t make a great deal of sense if you plan to use the
AP primarily in rooms on the other side of the kitchen. Passing through commonly
used interferers (all those metal appliances and especially that
microwave oven when it’s in use) generally isn’t a smart move.