Are you running NPM? Then you should have access to the Universal Device Poller tool which would allow you to create custom pollers for any SNMP based OID. Cradlepoint devices appear to be snmp capable and in a quick search I found the following for setting that up: Public Knowledge Base
We appear to have the MIBs already incorporated into the database. WIPIPE-MIB https://8535fe2169400172d177-ca20c12a60b762a27ac00022faae42ac.ssl.cf2.rackcdn.com/WIPIPE-MIB.txtIt looks like the signal strength OID would be 1.3.6.1.4.1.20992.1.2.2.1.4. This should get your started. You may want to create custom Views by Device Type for this gear. I walk through some of these methods and others here: SolarWinds Technical Training: Customizing the Orion UI - YouTube