To check for the misuse of frequency.

Hi Experts,

I want to know the action steps we can take for checking the misuse of your frequency by some other operator.
1.To identify the cells which are degraded by the Frequency Interference,even you have checked your frequency plan and there is no same frequency in the vicinity.
2.You can see it by Spectrum Analyser
(Anritsu,Agilent) they will show the frequency which is being interfered.Double check it by locking those TRx maybe at night.
3.To check for the Interferer operator what steps can we take, i
mean we have to check for its PLMN(CGI)to trace the culprit.

Can anybody throw some light further on this issue? It would be really helpful…….