Site Survey Considerations - Cisco Aironet 1600 Deployment Manual

Site Survey Considerations

Figure 56 Example of ClientLink (directing the signal to a client, in this case 1 spatial stream)
In order to beamform to clients using 3 spatial streams, since 3 transmitters are used in the transmissions
Note
the AP needs at least one additional radio to beamform. The AP 3600 has 4 radios pre band and can
beamform to clients using 3 spatial streams.
To summarize, ClientLink 2.0 takes the received signals heard from the client on the uplink, calculates
how the multipath signal looked from those streams, and then on the reciprocal side (transmit downlink)
figures out the optimal way using all four radios to best form the signal (transmit beamforming) to enable
the client to best decode (receive the signal on the downlink) with the least amount of retries.
ClientLink 2.0 with AP 3600 enables beamforming to all 802.11n clients, including 3SS clients, and can
do so for up to 128 clients at a time. Note AP 1600 supports less clients (32) and does not support 3-ss.
ClientLink 1.0 support a maximum of 15 clients at a time. ClientLink 2.0 significantly improves
throughput and coverage up to 60% on the downlink side for a much better 802.11n client connectivity
and enhancing the Bring Your Own Device (BYOD) experience.
For more information on Cisco ClientLink 2.0 refer to the following URL:
http://www.cisco.com/en/US/prod/collateral/wireless/ps5678/ps11983/at_a_glance_c45-691984.pdf
Site Survey Considerations
While ClientLink dynamically beamforms and helps to maintain a robust signal which results in fewer
retries, it was not designed to change the cell range. ClientLink creates a better connection experience,
not larger cell size.
For this reason, when conducting a survey it is important to keep in mind that the AP 3600 cell sizes
are generally the same or very similar to other Cisco Access Points. Figure 57 depicts typical ranges in
the 1-54 Mbps range. While it is always recommended to survey with the equipment you intend to
deploy, a previous survey done with say an AP 3500 – would not be invalid for an AP 3600 deployment.
Figure 58 and Figure 59 provide examples of the modulation types and signal-to-noise ratio (SNR).
Cisco Aironet Series 1600/2600/3600 Access Point Deployment Guide, Release 7.5
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