Aerohive access point, Руководство по развертыванию

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Chapter 1 Preparing for a WLAN Deployment
20 Aerohive
Figure 1 Omnidirectional antenna radiation patterns
The HiveAP can accommodate external antennas via coaxial jacks on its chassis (see "Antennas" on page 32 ).
The jack is a standard male RP-SMA connector. Various patch, directional, and omnidirectional antennas can be
used to change the coverage pattern. The most common external antennas are patch antennas. These are
directional antennas that provide coverage in a single direction. Most commonly they have a transmission
pattern as shown in
Figure 2 . Based on the gain, the signal will be wide (like the low gain antenna shown on top)
or narrow and long (like the high gain antenna shown on the bottom). Note that the coverage patterns are not
perfect for these antennas and that they often broadcast slightly in other directions than the primary one.
These extra "lobes" can be seen in both of the patterns shown below.
Figure 2 Directional antenna patterns
The following are some quick hints for deploying access points:
• Standard sheetrock walls and dropped ceilings are the best locations for mounting access points.
• When deploying WLANs in retail stores, doing a site survey at each store is likely to be impractical. It is more
common to run detailed site surveys at a few locations and use the results to set up deployment guidelines for
the remaining sites.
• Be aware of metal-lined firewalls, steel pillars, and other metallic surfaces. RF signals can reflect off metal
surfaces, which can cause unexpected coverage patterns. Also watch out for objects that can block or reflect
signals, such as mirrors, plants, walls, steel doors, elevator shafts, and bathroom stalls.
Toroidal Pattern Cardioid Pattern
Higher Gain
Lower Gain
(Bird’s Eye View)
Patch
Antennas
Higher Gain