Smartphone + Octagon...

yes... there are apps , like signal enigma2 finder etc...

connect the app (smartphone) to the same network , add ip user/pass ... and go on

the only way to do the job, is an application (as i think you can't do something from openwebif.)

Enigma Signal Meter - Android (this is an old version that i found in a quick search... you can download a new one)

take a look about the application and i think this is the better way to do the job (if you do not have a signal/field meter)