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

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

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.

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?

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.

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.

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.

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.

Dear Andrew,

Thanks for your reply. For clarification:-

What I understand form your suggestions is:- Instead of  adding the phasenoise profile into the large signal vsource, use another vsource with phasenoise profile file added to it.

I think in that scenarios, the vsource corresponding to the noise-source will have Source Type Setting:- DC, DC Voltage-0, Generate Noise- Yes and Noise File:- <the phasenoise profile file>.

Then use a vcvs for addition of the large signal Vsource with the noise Vsource.

But will it perform the same way of adding the the phasenoise profile into the large signal vsource ?

Kind Regards,

Dear Andrew,

Thanks for your reply. For clarification:-

What I understand form your suggestions is:- Instead of  adding the phasenoise profile into the large signal vsource, use another vsource with phasenoise profile file added to it.

I think in that scenarios, the vsource corresponding to the noise-source will have Source Type Setting:- DC, DC Voltage-0, Generate Noise- Yes and Noise File:- <the phasenoise profile file>.

Then use a vcvs for addition of the large signal Vsource with the noise Vsource.

But will it perform the same way of adding the the phasenoise profile into the large signal vsource ?

Kind Regards,

Yes, it should (as far as I know - I've not done experiments to confirm this though). You should also pick the Noise Type as being "SSB Phase Noise (dBc)" too to make sure the noise is generated correctly.

Regards,

Andrew.

Dear Andrew,

I tried. I set Source Type Setting:- DC, DC Voltage-0, Generate Noise- Yes and Noise File:- <the phasenoise profile file>.

I set the noisetype=SSB Phase Noise (dBc).

But it is giving error as:-

Error found by spectre during initial setup.
ERROR (CMI-2914): V1: To use noisetype=ssbphasenoise feature, the source type should be set to sine type
ERROR (CMI-2913): V0: At least one frequency in freqvec or in freq and freq2 should be greater than zero for noisetype=ssbphasenoise.

Er, good point. Sorry, I'd forgotten (and it makes complete sense) that the source has to be sinusoidal. You'll have to use a conventional noise file (I'm a bit nervous whether this will actually correctly correlate the noise in frequency if you do this though).

Might be worth contacting customer support so that we can think about this properly and answer it more robustly than a quick answer in the forums...

Regards,

Andrew.