Aerohive HiveAP 20, Руководство по развертыванию

Страница: 29 / 80

Chapter 2 The HiveAP 20 ag Platform
28 Aerohive
Antennas
The HiveAP 20 includes two fixed dual-band antennas with 3-dBi gains. These antennas are omnidirectional,
providing fairly equal coverage in all directions in a toroidal (donut-shaped) pattern around each antenna. When the
antennas are vertically positioned, coverage expands primarily on the horizontal plane, extending horizontally much
more than vertically. See
Figure 4 , which shows the toroidal pattern emanating from a single vertically positioned
antenna. To change coverage to be more vertical than horizontal, position the antennas horizontally. You can also
resize the area of coverage by increasing or decreasing the signal strength.
Figure 4 Omnidirectional Radiation Pattern
The pair of fixed dual-band antennas operate concurrently in two different frequency ranges: 2.4 GHz (IEEE
802.11b/g) and 5 GHz (IEEE 802.11a). Using two different frequency ranges reduces the probability of interference
that can occur when numerous channels operate within the same range. Conceptually, the relationship of antennas
and radios is shown in
Figure 5 .
Figure 5 Antennas and Radios
\
After connecting an external antenna to an RP-SMA connector, you must enter the following command to move the
appropriate interface from the adjacent fixed antenna to the external antenna:
interface interface radio antenna external
Note: To show the shape of radiation more clearly,
this illustration depicts the coverage provided by
only one active antenna and is not drawn to scale.
The omnidirectional antennas
radiate equally in all directions,
forming a toroidal pattern. HiveAP
Radio 1
RF 802.11b/g
2.4 GHz
Radio 2
RF 802.11a
5 GHz
Antenna
Switch 1 Antenna
Switch 2
RP-SMA Connectors
802.11a/b/g
Dual-Band
Fixed
Antenna
802.11a/b/g
Dual-Band
Fixed
Antenna
Cut-away view of the HiveAP to show the relationship
of the antennas and the two internal radios.