Re: Phase locked loop jitter at 1GHz
If you can convert phase noise @ offset to jitter RMS,
then there are many commercial PLLs (older vintage)
aimed at the cell phone space which ought to give you
good numbers for their reference designs. Presumably
at 1GHz you would use a >1GHz capable part (rated
frequency is often where the prescaler flakes out, plus
margin, not where you'd find the "sweet spot").
I'd recommend looking at Hittite, RFMD, Peregrine and
so on.
If you have a sine wave oscillator and a fixed noise
amplitude imposed on it, your jitter -will- follow 1/Fin
(because the prescaler input linear region divided by
dV/dt at prescaler input transforms voltage noise to
time noise).
But at 1GHz you might be able to (say) apply a square
(or square-ish) waveform from a LVDS or LVPECL source
and get a much better PN than from a sine output VCO.
If not, go for as much VCO amplitude as possible so as
to maximize dV/dt across threshold.