How to find IIP2 of system level design

like IIP3 , but write the equation of the IP2 , which is (F2-F1) , and here u go

khouly

IIP3 is determined by the interference in the adjacent channel because the 3rd order distortion components will locate in the interesting channel and degenerate the SNR. Similarly, if the receiver is zero-IF architecture, the 2nd order distortion components will also locate in the interesting channel and degenerate the SNR. Also the 2nd order distortion will cause time-varying DC-offset which will degenerate the zero-IF receiver performance too. So the IIP2 is determined by the interference and the reqirement of maximum DC-offset level.

hello,
Thanks for reply. Theory part I know, but having difficulti in practical mplementation.
My question was what should be Two tone for center frequency of 2.44GHz to measure IIP2?

You have to Mix down your RF to the IF, measure its Power (Pif) then
look for the IF's 2nd Harmonic and measure its Power (Pif2ndH).
Now subtract the Pif from the Pif2ndH and this is your /\ (delta)
/\ = (Pif - Pif2ndH)

IP2 = A + (/\ / (Order - 1)

A = RF Pin
Order = 2

Note the Eq. is valid for other orders
IP3--> (Order - 1) = (3 - 1) = 2
IP3 = A + (/\ / 2)

Getting the delta is not too clear to me either.

Hope this helps

about the delta these measure depend on getting the coeffeicent of the 2nd or third term for nonlinearity and get the IIP

if u inject the 2 tones to the mixer , the mixer will produce the difference between them without multiplying them to the LO , this is the result of the 2nd order nonlinearity

Khouly