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General Notes On Increasing Wireless Range
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Step 1: The
Desktop Fix:
Put a High powered USB WiFi adapter on your desktop.
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Step 2: The
Laptop Fix:
Most laptop cards have very poor receive sensitivity and
therefore have very limited range. Consider a high-powered USB
adapter. If you have a PCMCIA card, replace your laptop card
with a better card and consider additional antennas for those
cards that have external antenna connectors if your range is
greater than 75 - 100 feet.
Most likely, one
of the above steps will fix your wireless range problem. If not,
additional steps to consider are:
If you if you
are unsure what would be best for you feel free to call our
toll-free number 1-866-566-2919 and we will recommend the best
solution for you. If you want us to design a network for you we
offer a free design service. Just sign up for our design service. We
take a $175 deposit which is refunded to you when you purchase the
equipment from us that we recommend in our design (if you choose not
to purchase the equipment the design fee is not refunded). We have
been in the RF radio business since 1959 so if anyone can do it we
can.
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Step 4: The
Connecting Two Or More Buildings Fix:
If you are looking to share broadband with a neighbor's network,
or wish to connect to another building then consider a bridge
bundle.
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Step 5: Looking to just connect to a wireless router or wireless
access point outside your home or business ?
: Then consider an outdoor client radio, a complete power over
ethernet, outdoor radio with a high gain integrated antenna.
Understanding
802.11b & 802.11g (WiFi) Range
If your problem
is the wireless range of your laptop or desktop then read this and
follow the steps below.
Wireless networking (WiFi) at 2.4 GHz is a two-way system. Each
device must be capable of both sending and receiving a signal equal
distances. Think of it as two people, a substantial distance apart,
throwing a ball to each other.
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Person A has to be
strong enough to throw the ball, that substantial distance, to
person B. Person B also has to be strong enough to throw the ball
back, that substantial distance, to person A. If neither Person A
nor B can throw the ball that distance they will not have much of a
throwing game.
Access points and wireless routers (as shipped from the
manufacturer) have an advantage over laptop and desktop cards
because they have a higher output power and therefore have the
ability to send a signal further then most laptop and desktop cards.
When a higher-gain antenna is installed on a desktop card the output
power of that device is now increased closer to the output level of
the access point or wireless router therefore equaling the two
devices. In some cases, the antennas of both the access
point/wireless router and the desktop/laptop card may need to be
replaced. This is if the distance you are attempting to achieve is
greater than the capabilities of the access point/wireless router
when using the (factory) antennas that came with your card.
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Access Point To Client-side Device (WLAN/PCI
Adapter Card) |
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Output power of client-side devices with factory
antennas are less than that of access points. A
signal from an access point will travel farther
than that of the client-side device. |
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A high-gain antenna solution extends the range
of the client-side device, increasing its power
closer to that of the access point.
(solution dependent on specific situation
variables) |
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Please note that extending the range of your wireless 802.11b or
802.11g wireless device is only a piece of the whole puzzle. At
2.4GHz (the frequency that 802.11b and 802.11g WiFi operates at),
Line-Of-Sight can be an important
factor. Please see below regarding Line-Of-Sight.
Building-to-Building Connections: When connecting two or more
buildings it is best to first establish a wireless bridge between
the two points. If you want to be wireless within a building, once
the building-to-building bridge is created, then attempt to
establish a wireless network within each building or location.
Desktops, laptops, and other client devices will not work correctly
if the access point/wireless router is not resident in the building
where the access point/wireless router is located. You should
consider Step 4, at the top of this page, for this application.
Understanding The Importance Of Unobstructed Line-Of-Sight With
WiFi
Defining Line-Of-Sight
802.11b and 802.11g at 2.4GHz (equipped with and using a
vertically (or linear)-polarized antenna) requires unobstructed
visual Line-Of-Sight (LoS). Unobstructed Line-Of-Sight means just
that; there should not be trees, terrain, buildings, or structures
between your two (antenna) points. Basically both antennas should
physically see each other in an external outdoor bridge. The radio
waves at this low frequency will not penetrate metal, steel,
concrete, cement, stone, brick, etc. very well, if at all. For
interior applications, dry wall, sheet rock, and wood shouldn't be a
problem.
Surrounding the visual Line-Of-Sight is the Fresnel zone (image 1).
Any obstructions that come into the Fresnel zone, although not
obstructing the visual Line-Of-Sight, may also slow down, hinder and
effect your signal. The radio waves may deflect off of those
obstructions. This is called Near Line-Of-Sight (nLoS, image 2).
Although you may see a slight signal with nLoS situations, your data
transfer rate may decrease. You may find you are incapable of
accessing the Internet. An obstruction that cuts across the visual
Line-Of-Sight and prohibits an optical visual between the two
antennas in your bridge is considered Non-Line-Of-Sight (NLoS, image
3). Any signal, in this case, will be minimal or non-existent

You may find in your bridge application that the two antennas can
visually see each other through spaces and breaks in an
obstructing tree or tree line. Please note that tree branches that
cross the visual Line-Of-Sight will move with the wind. This
movement will disrupt and have an effect on a vertically-polarized
WiFi signal. Keep in mind, if you are conducting your site survey
during late Fall and Winter months, those trees will fill in come
Spring and Summer. Additionally, weather, RF interferences, and
other site variables can have an effect on your signal too.
Linear (Vertically) -Polarized vs. Circular-Polarized
Most WiFi, 802.11b and 802.11g, antennas on the market today are
linear (or vertically) -polarized. This includes the small, "rubber
ducky" antennas that ship from the factory with most wireless
devices.
A radio wave travels through the air about the size of a pine
needle. If the antenna is vertically polarized the pine needle must
remain vertical, as sent. If the signal hits an obstruction the
signal will flip or rotate into multiple positions as it gets to the
receiving radio's antenna where it will be seen as noise. The
vertically-polarized antenna will not capture that signal. In a
circular-polarized antenna, the plane of polarization rotates in a
corkscrew pattern making one complete revolution during each
wavelength. A circularly-polarized wave radiates energy in the
horizontal, vertical planes as well as every plane in between. If
the rotation is clockwise looking in the direction of propagation,
the sense is called right-hand-circular (RHC). If the rotation is
counterclockwise, the sense is called left-hand-circular (LHC).
If you have any specific questions, please do
not hesitate to
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