With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cwrMinTxPower
Cisco Wireless Minimum Tx Power
1.3.6.1.4.1.9.9.136.1.5.1.1.8
This object represents the minimum power that the RF subsystem can supply the antenna.
Back to CISCO-WIRELESS-IF-MIB MIB page.
IPHost Network monitor allows you to monitor cwrMinTxPower 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.