Aerohive access point, Deployment Manual

Page: 58 / 221

Deployment Guide 57
H
IVE
AP 340 P
RODUCT
O
VERVIEW
Figure 5 HiveAP 340 antennas
MIMO
MIMO (Multiple In, Multiple Out) is a major WLAN advancement introduced in the IEEE 802.11n standard in which
multiple RF links are formed on the same channel between the transmitter and receiver simultaneously. To
accomplish this, the transmitter separates a single data stream into multiple spatial streams, one for each RF chain
(an a various digital signal processing modules linked to the antenna). The transmit antennas at the end of
each RF chain then transmit their spatial streams. The recipient’s receive antennas obtain streams from all the
transmit antennas. In fact, due to multipath, they receive multiple streams from each transmit antenna. The
receive antennas pass the spatial streams to the digital signal processors in their RF chains, which take the best data
from all the spatial streams and reassemble them into a single data stream once again (see
Figure 6 ).
Figure 6 2x2 MIMO (2 transmit antennas x 2 receive antennas)
5 GHz Antenna for IEEE
802.11a/n
Length when fully
extended: 5 15/16” (15 cm)
2.4 GHz Antenna for
IEEE 802.11b/g/n
Length when fully
extended: 7 7/8” (20 cm)
The base of the antennas hinge up to 90 degrees so that you
can orient the antennas independently of the orientation of
the HiveAP chassis. The antennas also rotate in a full circle.
When mounting the HiveAP
340 on a ceiling, orient its
antennas downward.
When mounting the HiveAP
on a wall or post, fully extend
its antennas upward and
downward.
When mounting the HiveAP
above a ceiling or on a
horizontal beam, orient its
antennas upward.
Generally, orient the antennas vertically for
improved radio coverage, as shown here:
Transmit
Antennas
Digital Signal
Processors
RF Chains RF Signals (Multipath)
Receive
Antennas
Digital Signal
Processors
RF Chains
802.11n wireless client
with two antennas
HiveAP 340 using
two antennas
Object
Data
Reassembled
Data