With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cd11IfClientTxPowerEntry
Cisco DOT11 Interfaces Client Tx Power Entry
1.3.6.1.4.1.9.9.272.1.1.2.13.1
Each entry specifies the number of available transmit power levels, the values of all the levels, and the selected level for a radio interface.
Back to CISCO-DOT11-IF-MIB MIB page.
IPHost Network monitor allows you to monitor cd11IfClientTxPowerEntry on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco routers right now.