Request for Support on Central Frequency Issue in AWR Software

Good Morning everyone,

I am writing to seek your assistance regarding an issue we are facing with the AWR software, specifically related to the usage of the central frequency (fc) when applying a tone.

 As we understand, if the central frequency is left blank, it defaults to the average value of all the tones in frequency. However, when we set the central frequency to zero (fc = 0), we encounter phase problems in the signal, with the phase varying between 180° and -144°. We would like to better understand why this behavior occurs and how it can be mitigated.

 Additionally, when using a mixer, we need to assign a non-zero central frequency to the “LO” input, as the simulation does not start if fc = 0 is used. However, for our application, it is crucial that we work with fc = 0. We have attempted to set fc to 10e(-30) as a workaround, but this leads to further complications in the simulation.

 Could you please advise me on how to resolve this issue and ensure that the simulation runs smoothly with fc = 0? We would greatly appreciate your guidance on this matter.

Thank you  for your support.

P.S. i’m sending you an image where is it possible to spot the phase varying problem in blue line with 2 markers ( fc = 0 ). With pink line ( fc left blank ) you can see that the phase’s tone is 0. Lastly, you can see that the brown line ( fc = e-30 ), is entirely covered by the blue line ( fc = 0 ).