Stats

Locked Locked
Replies 11
Subscribers 64
Views 18220
Members are here 0

This discussion has been locked.

You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Adding same (fully correlated) Phase-noise to two LO paths

RFStuff over 7 years ago

Dear All,

I have 4 LO paths (LO0, LO90, LO180 and LO270) with 25% duty cycle clock output wave forms.

These wave forms are almost squarish and captured form another LO generation circuit simulation.

Currently, I using the captured files of the 4-waveforms for PSS/Pnoise simulation of the receiver circuit.

I want to add phasenoise to the 4 LO paths. I have a phase-noise profile file.

But, the important thing I want is :- The phasenoise of LO0 and LO180 should be completely co-related and the phasenoise of LO90 and LO270 should be completely co-related.

How this can be achieved.

Could anybody please help in this regard.

Kind Regards,

Parents

Frank Wiedmann over 7 years ago

I guess that you could create two correlated noise sources by feeding two controlled sources (like vcvs) with the same noise source.
Cancel
Vote Up 0 Vote Down

Cancel
RFStuff over 7 years ago in reply to Frank Wiedmann

Hi Frank,

Thanks for your reply.

Each LO is given though the port which contains the captured file of the LO waveform.

The phase noise is added by adding the phasenoise profile file to the PORT.

So, through VCVS it can not be done.
Cancel
Vote Up 0 Vote Down

Cancel
Frank Wiedmann over 7 years ago in reply to RFStuff

How about using a single port together with the ideal_balun component (see also http://www.designers-guide.org/Analysis/diff.pdf) to generate the correlated LO signals?
Cancel
Vote Up 0 Vote Down

Cancel
RFStuff over 7 years ago in reply to Frank Wiedmann

But then how I will get LO180 with 180 degree phase shifted.?

The LO pulses are NOT symmetric rather they are 25% duty-cycle clocks.
Cancel
Vote Up 0 Vote Down

Cancel
Andrew Beckett over 7 years ago in reply to RFStuff

Have the noise sources separate from the large signal sources and then add them together (e.g. with the output of each vcvs in series with the large signal pulse source). BTW, the vsource allows noise to be generated as an SSB Phase Noise (this is the "Noise Type" parameter).

Regards,

Andrew.
Cancel
Vote Up 0 Vote Down

Cancel
Frank Wiedmann over 7 years ago in reply to RFStuff

Sorry, I had overlooked this detail. So I'm back to my first proposal: add the noise generated by a vsource with a noisefile by using controlled sources.
Cancel
Vote Up 0 Vote Down

Cancel

Reply

Frank Wiedmann over 7 years ago in reply to RFStuff

Sorry, I had overlooked this detail. So I'm back to my first proposal: add the noise generated by a vsource with a noisefile by using controlled sources.
Cancel
Vote Up 0 Vote Down

Cancel

Children

Andrew Beckett over 7 years ago in reply to Frank Wiedmann

Apologies for my repetition of Frank's suggestion - unfortunately there's a "feature" (well, a bug) of the forums that we've raised with the software provider which happens with Apple Mail (on iPhone and Mac) which some causes email notifications in the same thread to vanish (I know the root cause, but they've not fixed it yet).

Regards,

Andrew.
Cancel
Vote Up 0 Vote Down

Cancel

Community Guidelines

The Cadence Design Communities support Cadence users and technologists interacting to exchange ideas, news, technical information, and best practices to solve problems and get the most from Cadence technology. The community is open to everyone, and to provide the most value, we require participants to follow our Community Guidelines that facilitate a quality exchange of ideas and information. By accessing, contributing, using or downloading any materials from the site, you agree to be bound by the full Community Guidelines.