Cisco 8821 Manual page 45

Beamforming (ClientLink)
Enable ClientLink if using Cisco 802.11n capable Access Points.
For releases prior to 7.2.103.0, ClientLink can be enabled globally via the 802.11 Global Parameters section or on individual
access points via the access point's 802.11 radio configuration page.
As of release 7.2.103.0, ClientLink is no longer configurable via the Cisco Wireless LAN Controller's web interface and is
only configurable via command line.
With releases 7.2.103.0 and later use the following commands to enable the beamforming feature globally for all access points
or for individual access point radios.
(Cisco Controller) >config 802.11a beamforming global enable
(Cisco Controller) >config 802.11a beamforming ap <ap_name> enable
(Cisco Controller) >config 802.11b beamforming global enable
(Cisco Controller) >config 802.11b beamforming ap <ap_name> enable
The current status of the beamforming feature can be displayed by using the following command.
(Cisco Controller) >show 802.11a
(Cisco Controller) >show 802.11b
Legacy Tx Beamforming setting....................
Cisco Wireless IP Phone 8821 and 8821-EX Wireless LAN Deployment Guide
Enabled
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