Chapter 2: Installing the Access Points
External Antenna Placement Guidelines
Connecting Antennas to the Radios
Positioning Antennas for 802.11g, 802.11b, and 802.11a Radios
Antennas and their placement play a vital role when installing a wireless network. Every wireless network environment presents its own unique obstacles. Therefore, the exact range that you will achieve with each access point is difficult to determine. Allied Telesyn recommends that you allow an Allied
Radio signals may reflect off some obstacles and be absorbed by others. For example, two radios may achieve up to 305 m (1,000 ft) of range if positioned outdoors within line of sight, with no obstacles between them. However, the same two radios may only achieve 152 m (500 ft) of range when the RF signal has to travel through items such as cubicles. If the signal must penetrate office walls, the signal range may decrease to 91 m (300 ft).
Using the proper antennas for your environment and placing them in the proper areas can help improve range. For information about antenna options, contact your local Allied Telesyn representative. Here are some general guidelines for positioning antennas:
Place the antenna as high as possible. In an office environment, try to place it above cubicle walls.
Keep the
Do not place a sheet of metal (such as a filing cabinet) between two antennas.
These next sections provide detailed information about antenna placement for those access points that can have more than one antenna.
All radios have two ports. The radio in slot 2 uses ports 3 and 4, and the radio in slot 2 uses ports 1 and 2. If you have only one radio in the access point, it is in slot 1.
For the 802.11g and 802.11b radios, the primary port is a transmit/receive port and the secondary port is a
For the 802.11a radio, both ports are automatically transmit/receive ports, You can attach antennas to both ports and it will automatically use antenna diversity or you can attach one antenna to either port.
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