Thanks Karl for your respond. Actually I want to do something else, but to check my understanding, I just fall back to a very simple case. My initial thought is in this co-channel case, the Unwanted interference and Blocking Interference (with default User Defined Blocking mask) are the same. But it is not the case.
Studying the manual, Calculation of total emissions, does not give me a very clear procedure to reproduce this result. I did try several times but end up in nowhere near the value: -1.9808567249667528 dBc. Trying to change the interfering Tx emission mask yields other value.
Do you aware of a simpler explanation/procedure or should I have to study the source code?
Regards,