One of potential customers asked about the IMD performance and I think it is a good question. I have to clarify here when I wrote spurious suppression of -50dBc. It is actually for harmonics of 2nd and 3rd and other parasitic oscillations. If we check closely near the carrier frequency with a spectrum analyzer, the IMD products of 3rd, 5th are quite strong. The measured IMD 3rd is not good, which will generate strong overtone in waterfall spectrum and cause nearby channel interference. During design phase, I have noticed it but I have to balance the RF output from the design simplicity with this spec. I also noticed that the carrier leakage without audio modulation is strong too, and it is even higher than the 3rd IMD products.
Those are the facts and I hope you can understand and help improve if you can. Thank you.
