ads warning"more than one mixing item has landed on frequency xHz "

[maxsidou]

hi, all. in ads (keysight) simulation of one mixer, there is a warning"more than one mixing item has landed on xHz". Does it mean there is shared frequency jamming or something shared frequency interference? Or Could it be explained that more mixing item on one frequency is good because the power of this frequency point is strengthened by many mixing items? welcome any comment~

 

[BigBoss]

If there are two HB Frequencies analytically Related-for instance 100MHz and 200MHz- 2^nd Harmonic of 100MHz lands on 200MHz and creates a Collision.Therefore you should select HB Frequencies more or less NOT related.Shift one of them 1MHz, see what happens..

 

[maxsidou]

If there are two HB Frequencies analytically Related-for instance 100MHz and 200MHz- 2^nd Harmonic of 100MHz lands on 200MHz and creates a Collision.Therefore you should select HB Frequencies more or less NOT related.Shift one of them 1MHz, see what happens..

Yes, BigBoss. It is a fundamental mixer and I want to verify that whether the 2nd harmonic of the LO signal affect the mixing. the simulation setup is shown is the figure and LOfreq2=2*LOfreq. the simulation results shows that besides the most strong signal created by LOfreq, there are also some weak weak signal. does the weak signal affect the signal or it is also a signal? if no LOfreq2 in HB setup or shift it by 1MHz, only one signal found in one frequency.

 

[BigBoss]

Your HB Set-Up is wrong.LOfreq has already 2^nd Harmonic so you don't have to define "a second harmonic" more..
See HB examples in ADS installation and learn how to set-up..