I have some problem in prediction of 3-rd order
inter-modulation product level
Usually, IMP3 is defined analytically for the case that
both tones are of the same level and frequency difference
between them is less than 5% of their frequency (in-band
I have a different case: f1 tone is of 49
dBm at 430 MHz, and f2 tone is of 29 dBm at 549 MHz. So,
they have different levels and are spread wide.
interested to predict the level of lower IMP3 (2*f1-f2) at
I am looking for analytical equation and
physical/mathematical explanation, which will take in
account the wide distance between tones at frequency axes
and also their difference in power levels.
theoretical explanation and/or links will be appretiated.
I look also for translation between measurement results
taken by classical approach and my special case.
example, I have to understand whether results of classical
measurement of OIP3 may be applied somehow to my special
case and reliably predict "my" IMP3 at 311 MHz.