BSIM4
New Member
Offline
Posts: 8
|
I will take a guess here since more details would help to identify the problem.
The little bump might be caused by the image of the mixer. Why you do not see it with perfect LO? I think it is because with larger steps and a very, very sharp LO, your frequency sweep simply stepped through the peak at exactly 200MHz. When you used a real VCO, reciprocal mixing widened the peak at 200MHz, so you can see it with your current sweeping set-up.
To check if this is true. add 200MHz point to your frequency sweep setup and see if you can see the peak caused by imaging.
|