CXtec NEW COMPATIBLE 2.2 DBI RUBBER DUCK ANTENNA WITH RPTNC FEMALE Guia De Especificaciones
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The Network Connections
The access points use a 10/100-Mb Ethernet connection. Typically the access point is in the same location as the antenna. While it may seem that the
best place to put the access point is in a wiring closet with the other network components, such as switches, hubs, and routers, this is not the case.
The antenna must be placed in an area that provides the best coverage (determined by a site survey). Many people new to wireless LANs want to
locate the access points in the wiring closet and connect the antenna using RF coax. Antenna cable introduces losses in the antenna system on both
the transmitter and the receiver. As the length of cable increases, so does the amount of loss introduced. To operate at optimum efficiency, cable runs
should be kept as short as possible. (See the section on cabling later in this document).
Building Construction
The density of the materials used in a building's construction determines the number of walls the RF signal can pass through and still maintain
adequate coverage. Following are a few examples. Actual effect on the RF must be tested at the site, and therefore a site survey is suggested.
Paper and vinyl walls have very little effect on signal penetration. Solid walls and floors and precast concrete walls can limit signal penetration to
one or two walls without degrading coverage. This may vary widely based on any steel reinforcing within the concrete. Concrete and concrete block
walls may limit signal penetration to three or four walls. Wood or drywall typically allow for adequate penetration through five or six walls. A thick
metal wall reflects signals, resulting in poor penetration. Steel-reinforced concrete flooring will restrict coverage between floors to perhaps one or
two floors.
Recommendations for some common installation environments are outlined below:
•
Warehousing/Manufacturing—In most cases, these installations require a large coverage area. Experience has shown that an omnidirectional
antenna mounted at 20 to 25 feet typically provides the best overall coverage. Of course, this also depends upon the height of the racking, material
on the rack, and ability to locate the antenna at this height. Mounting the antenna higher will sometimes actually reduce coverage, as the angle of
radiation from the antenna is more outward than down. The antenna should be placed in the center of the desired coverage cell and in an open area
for best performance. In cases where the radio unit will be located against a wall, a directional antenna such as a patch or yagi can be used for
better penetration of the area. The coverage angle of the antenna will affect the coverage area.
on the rack, and ability to locate the antenna at this height. Mounting the antenna higher will sometimes actually reduce coverage, as the angle of
radiation from the antenna is more outward than down. The antenna should be placed in the center of the desired coverage cell and in an open area
for best performance. In cases where the radio unit will be located against a wall, a directional antenna such as a patch or yagi can be used for
better penetration of the area. The coverage angle of the antenna will affect the coverage area.
•
Small Office/Small Retail—The standard dipole may provide adequate coverage in these areas depending on the location of the radio device.
However, in a back corner office a patch antenna may provide better coverage. It can be mounted to the wall above most obstructions for best
performance. Coverage of this type antenna depends on the surrounding environment.
performance. Coverage of this type antenna depends on the surrounding environment.
•
Enterprise/Large Retail—In most cases, these installations require a large coverage area. Experience has shown that omnidirectional antennas
mounted just below the ceiling girders or just below the drop ceiling typically provide the best coverage (this will vary with stocking, type of
material, and building construction). The antenna should be placed in the center of the desired coverage cell and in an open area for best
performance. In cases where the radio unit will be located in a corner, or at one end of the building, a directional antenna such as a patch or yagi
can be used for better penetration of the area. Also, for areas that are long and narrow—such as long rows of racking—a directional antenna at one
end may provide better coverage. The radiation angle of the antennas will also affect the coverage area.
material, and building construction). The antenna should be placed in the center of the desired coverage cell and in an open area for best
performance. In cases where the radio unit will be located in a corner, or at one end of the building, a directional antenna such as a patch or yagi
can be used for better penetration of the area. Also, for areas that are long and narrow—such as long rows of racking—a directional antenna at one
end may provide better coverage. The radiation angle of the antennas will also affect the coverage area.
•
Point-to-Point—When connecting two points together (such as a wireless bridge), the distance, obstructions, and antenna location must be
considered. If the antennas can be mounted indoors and the distance is very short (several hundred feet), the standard dipole or mast mount 5.2dBi
omnidirectional may be used. An alternative is to use two patch antennas. For very long distances (1/2 mi. or more), directional high-gain antennas
must be used. These antennas should be installed as high as possible, and above obstructions such as trees, buildings, and so on; and if directional
antennas are used, they must be aligned so that their main radiated power lobes are directed at each other. With a line-of-site configuration,
distances of up to 25 miles at 2.4 GHz and 12 miles at 5 GHz can be reached using parabolic dish antennas, if a clear line-of-site is maintained.
With the use of directional antennas, fewer interference possibilities exist and there is less possibility of causing interference to anyone else.
omnidirectional may be used. An alternative is to use two patch antennas. For very long distances (1/2 mi. or more), directional high-gain antennas
must be used. These antennas should be installed as high as possible, and above obstructions such as trees, buildings, and so on; and if directional
antennas are used, they must be aligned so that their main radiated power lobes are directed at each other. With a line-of-site configuration,
distances of up to 25 miles at 2.4 GHz and 12 miles at 5 GHz can be reached using parabolic dish antennas, if a clear line-of-site is maintained.
With the use of directional antennas, fewer interference possibilities exist and there is less possibility of causing interference to anyone else.
•
Point-to-Multipoint Bridge—In this case (in which a single point is communicating to several remote points), the use of an omnidirectional
antenna at the main communication point must be considered. The remote sites can use a directional antenna that is directed at the main point
antenna.
antenna.