Hi,
External Antenna Deployments:
All Cisco antenna connectors are labeled; “A,” “B,” “C,” and so on. “A” has a higher priority than “B” or “C/D” so, if the AP supports say 3 or 4 antennas and you only have 2 antennas, you can use them on ports “A” and “B” for a short term until you install the additional antennas.
While it is not recommended that you use less antennas–the product (in a pinch) supports 802.11a/b/g clients or single spatial stream N clients using only one or two antennas. However, there is a significant performance hit and you will lose ClientLink functionality. Should you do this, you might also have to configure the AP in the software so as not to use the other antennas.
Regards
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