mixer mxn spurs
Hittite gives spurious output tables for downconversion and LO spurs for upconversion.
See
http://www.hittite.com/content/docum...eet/hmc141.pdf
Isn't all the information for UP- and DOWNconversion included in the nLOxmRF table ?
You know, 0*RF + - nLO should be the same as the LO harmonics ?
RIGHT ?
Thank you
elektr0
The actual spur table depends on conversion type. There may be some different scenarios like RF>IF and LO is constant, the same but LO is variable and so on. You may consider case 0*RF+/-n*LO as LO harmonics only for an ideal mixer. For real mixer 0*RF is DC and it will affect the mixer performance, often dramatically. This is one of the major problems with direct conversion systems.
Hello,
thank you for answering.
Do you mean spurious output from the amplifier or mixers ?
2f1-f2.....?
elektr0
No, only downconversion. "Measured as downconverter" is written in the table "MxN Spurious @ IF Port" on page 4-23.
Yes. LO harmonics level at the IF port. There is another table "Harmonics of LO" on page 4-23 showing LO harmonics level at the RF port.
I told about mixers. Amplifier is a totally different story.
@VSWR.
Yes, I also read this sentence "...Downconversion.." but is it valid to use the same spur values for the upconversion case.
@RF-OM:
The situation with GaAs amplifiers is quite similar.
It is the third order nonlinearity, which produces 2*f1-f2, ... spurs.
Down conversion and up conversion are different for any kind of mixer. The products depends on mathematical equations and they are different for these two processes.
Amplifier non-linearity and mixer are two different things. They described with the same math, but what is good for mixer is very bad for amplifier. Mixer third product may have much more amplitude than it is for amplifier.