I have a cable modem that delivers 6Mbps of Internet speed when my
computer is physically connected, but only 1.5Mbps when I go wireless.
 The speed reduction occurs with or without encryption and I have
tried ?b? and ?g? wireless routers.  How can I wirelessly get the
Internet speed I am paying for?

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Clarification of Question by questionfromboston-ga on 22 Sep 2005 12:59 PDT

I have tried this with numerous adapters, computers and routers,
always with full signal strength (the computer very near the router),
but I have never gotten wireless Internet speeds to exceed about
1.5Mbps.

This could be explained by either interference, a bad adapter in the
computer, or the distance from your router. To answer this question
properly, I would need to know the distance from your computer with
the wireless adapter (and what kind it is) and the wireless router
you're trying.

Even 802.11b routers should offer about 4 to 6 Mbps with or without
encryption; an 802.11g (plain, no enhancement) router should move
about 20 to 25 Mbps.

But these are speeds at the highest level of signal strength without
nearby networks causing interference on the same wireless channels
that can reduce rates.

Based on what you say, I would expect your computer has a wall between
it and the router, and that you are in an apartment complex or a dense
neighborhood with other networks nearby.

I agree with the above explanation. I have been working for microsoft
wireless support for 2 years.

Wireless routers, access points, and adapters send and receive radio
wave signals through antennas. The antenna is hidden inside adapters,
but on routers and access points there's a visible antenna. Radio
waves can be focussed like a lightbulb. And like a light, some
materials reduce or stop radio waves. While light focused from several
lights is brighter and makes it easier to see, several antennas in the
same area cause interference ? the radio signals will be muddy and
confused. Try to change the channel numbers on the router settings.

Your goals in optimizing power are:

Avoid obstacles. 
Avoid interference. 
Increase signal strength. 

Power affects how far an antenna radiates. 
Use the equipment in places it's most powerful and most sensitive. 
Antennas don't radiate equally in every direction. Just as the base of
a lightbulb blocks light, and just as a light can be focussed by a
reflector, so an antenna signal may be blocked and focused. Since
people cannot see radio waves, you'll rely on testing and
trial-and-error to get an idea of where antennas "shine" most
brightly. An adapter's antenna is important, but the most powerful and
sensitive antennas are on routers, access points, and detachable
external antennas.

The focus of an antenna is either omni-directional antenna or
directional. "Omnis" are used in most home products, they radiate
horizontally all around, but are weaker upward or downward. When
visible, these antennas are usually a rod a few inches long. A
directional antenna radiates strongly in a limited direction. It is a
flat panel or a dish. These are used for point-to-point transmissions
(where two antennas are focused directly at each another). These need
a line of sight between them, and preferably a large open space around
the main beam.

When you are near antennas you'll still get a signal, even if you are
out of the direction of its strongest signals. But when further away,
you have to be in the direction the beam is the most powerful and
unobstructed to receive it.

One final concept before you go to the above links is interference.
Interference is a signal ? one you don't want ? at the same frequency
as the one you're using. Interference comes from devices such as
microwave ovens, cell phones, 2.4 GHz cordless phones, and copy
machines. Interference is also caused when your own wireless signals
are bounced off reflecting objects. Objects may partly or completely
absorb signals, reflect them, bend them, or let them pass right
through. Metal and water (including the water in people!) absorb or
reflect signals. Air, wood, and glass tend to let signals pass with
weakening. And when outdoors, plants and the weather may cause
interference.

Again the following may further help u resolve ur issue

Improving Wireless Range: Tuning Equipment 
Using the best channels has a big effect on network performance. Your
goal is to choose settings that avoid interference from other
networking and radio frequency equipment. (If you have 802.11a or
802.11a/g, channel selection is less important, skip to "Reducing
Wireless Network Traffic".)

If you have a simple home network, and aren't close to neighbors with
wireless equipment, you may be lucky enough just to choose between
many channels that work well.

Complications arise when:

You want much better coverage than you're getting. 
You use multiple access points or wireless routers. (Then you'll
probably be using more than one channel.)
You aren't the only person nearby running a wireless network. 


improving signal strength is not like adding more lights to get a
brighter livingroom. Devices that transmit powerfully ? such as
routers, access points, and cell phone base stations ? confuse one
another. It's necessary to distance them and to have them use
different channels.

For 802.11b and 802.11g, there are 11 channels for wireless equipment
(13 channels in Europe). In the simple situation where there's little
interference, you can choose any channel that works for you. When
there is interference from wireless networks that overlap with one
another, each network should use one of the non-overlapping channels:
1, 6, or 11 (1, 7, 13 in Europe). Then, 3 networks can use the same
space with minimum interference. If you can't do that, choose channels
as widely spaces as possible


If your neighbor has a wireless network, it wouldn't be surprising
that they are already using channel 1 and channel 11. Unfortunately,
you can't completely avoid interference just by using other channels.
Wireless protocols 802.11b and 11g only have 3 non-overlapping
channels. Therefore when 4 or more channels are used in the same area,
the level of interference can increase notably. If you and your close
neighbor both have a router and a wireless access point, for example ?
which makes a total of four powerful transmitters ? both of you will
have a certain amount of interference.

If there's a severe problem, a practical and sociable thing is to talk
to your neighbors using wireless networks that can be seen when you
scan. Together, you can choose optimal channels for your respective
networks. You'll want your own channels at least 5 apart. So, for
example, you could use channels 1 and 8, and your neighbor could use 5
and 11.

You may be able to place routers and access points further away inside
your homes. After all, the kinds of physical barriers that reduce your
transmission range also reduce the signal that your neighbor doesn't
want to see.

U can also use the following which may help u 

When SSID Broadcast is turned on, it's easiest for equipment to find
the strongest signal. However this also causes network overhead. When
the SSID is broadcast, your neighbor's equipment may keep a record of
it, and automatically try to connect several times a second; this can
cause significant performance reduction. So where there are close
networks, turn off SSID Broadcast, and change the default SSID.

Turning off WEP and WPA may increase network throughput, but exposes
your network to hackers. This is not recommended, except for testing
purposes.

I am starting a science project on this question and I will happily
give you any information that comes up after I finish my experient.
Before I even started this experiment I believed it had to do with
your houses building material. This may effect it because your base
stations may have to try to go threw to many materials that will
effetc its range and/or strength. I will keep you posted.