With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cwrAntennaGain
Cisco Wireless Antenna Gain
1.3.6.1.4.1.9.9.136.1.10.1.1.6
This object represents the gain of this antenna.
Back to CISCO-WIRELESS-IF-MIB MIB page.
IPHost Network monitor allows you to monitor cwrAntennaGain on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco switches right now.