Cisco Aironet 1600 Deployment Manual page 7

Figure 6 Side View of AP 3600 (2.11 inches) and AP 3500 (1.84 inches) in height
The AP 3600e (external antenna version) differs in appearance from the AP 3500e, having fewer antenna
connector ports primarily due to the dual-band antenna system that is used.
The AP 3500e has separate antennas for each band, 2.4 GHz and 5 GHz, and does not support 3SS
technology since it has only two transceivers (transmitter/receiver) and one extra receiver per band
enabling operation up to two spatial streams.
The AP 3600e has combined all the antenna ports (dual-band) so that each antenna port can transmit
simultaneously on each band; had the antenna ports not been combined, this would have required 8
antennas. The AP 3600 has four transceivers (transmitter/receiver) radio ports per band for a total of
eight transceiver, four in each band. This additional radio per band permits beamforming to 3SS clients
using ClientLink 2.0 to improve the overall performance of all 802.11n clients with 1, 2 and 3 spatial
streams.
Note Beamforming to a 3SS client requires n+1 RF design. To accomplish this, the AP 3600 has an additional
radio per band, which improves client performance by using Cisco ClientLink 2.0.
Unlike AP 3500, the newer AP 3600 design supports an additional feature module. The bottom of the
AP 3600 unit looks different as it has openings to support the feature module. The openings, while fully
sealed, permit the module to have access to the topside of the AP to allow the module antennas (if present
in the module being used) to fully function. The unit includes a positive snap "spring loaded BB" so the
installer can feel a positive lock when the AP is fully engaged in the bracket
Figure 7 Bottom of AP 3600 Unit
Cisco Aironet Series 1600/2600/3600 Access Point Deployment Guide, Release 7.5
Choosing the Right Access Point
(Figure 7).
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