Teletronics International Inc SAMP24W ユーザーズマニュアル

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Extended Range Amplified WLAN System Guide
 
 
Version 07/18/02 
 
 
Table 1-1 and Table 1-2 list the following antenna types: 
 
• 
Omni-directional antennas have a 360-degree coverage pattern on a horizontal plane for 
multipoint and mobile applications where wide coverage is desired. 
• 
Directional antennas (Patch, Grid, Dish) concentrate the coverage pattern in one direction.  This 
produces a conical-shaped main lobe.  The antenna directionality is specified by the angle of the 
beam width.  Typical beam width angles are from 90 degrees (somewhat directional), to as little 
as 20 degrees (very directional).  The directed beam allows for a longer but narrower coverage 
pattern, which is ideal for elongated areas, corners, and outdoor point-to-point applications. 
Calculating Range: 
For an unobstructed outdoor site, each 1dB increase in gain results in a range increase of approximately 
5%.  The coverage pattern may vary depending on the amount and type of obstructions at the site.  
Positioning antennas: 
The proper positioning (orientation) of antennas at a site helps ensure the maximum coverage area.  
Antenna should generally be mounted as high and as clear of obstructions as practically possible.  Best 
performance is attained when both transmitting and receiving antenna are located at the same height and 
in a direct line of sight of each other.  Access Points should be positioned on or close to the ceiling.  
Place omni-directional antennas in the center of the coverage area when possible.  When ceiling mounted, 
try to keep antennas at least two feet from sprinkler heads, metal lighting fixtures, etc.  
For directional antennas, point at the direction of the coverage area.  All antenna characteristics are the 
same for both transmit and receive.  For outdoor mounting of antennas note that the coaxial RF cable 
should be kept as short as possible to minimize RF loss - the length of cable that comes with the antenna 
is optimized.  Use coaxial cable extensions if needed, available on our 
 page - however, 
placing the Access Point close to the antenna and bringing the Ethernet cable to the Access Point is 
preferred.  
Please review the variety of optional antennas that are available at 
Teletronics offers several omni-directional and directional antenna to provide for optimum coverage and 
performance.  
5  Post Installation Testing 
5.1  Basic System Operational Checks 
Basic system operational checks are performed using the system diagnostic LED indicators on the Cisco 
Aironet and DC Injector module devices.  Power on the fixed site network, and all wireless LAN system 
devices and verify the following: