deba
|
Hi,
I have few question regarding pnoise available in spectreRF.
1) For a square wave, the phase information is only present at the rising or falling edges. Thus, the phase noise(in dBc/Hz) obtained from noisetype=sources will be equal to the one obtained from the one using noisetype=pmjitter(the voltage noise is converted to phase noise).
Is the above reasoning applicable to sinusoid oscillators(VCO,crystal)? I think pmjitter cannot be applied to these cases. So if there are sinusoid then only noisetype=sources is applicable.
2) For a driven circuit, if one limits the amplitude using a VCVS(limiter with gain=1 around the threshold crossing) and use noisetype=sources. The phasenoise obtained using this method will be the same as the one obtained using pmjitter. So the utility of pmjitter is not clear. Can someone clarify?
Thanks
|