Understanding External Antenna Deployments - Cisco Aironet 1700 Deployment Manual

Figure 47 Radiation Patterns for the AP 1600i @ 2.4 GHz
Figure 48 Radiation Patterns for the AP 1600i @ 5 GHz

Understanding 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.
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