injection locked oscillator phase noise simulation using pss+pnoise

Hi all,

I am designing an injection locked vco.  My simulation scenario for the phase noise is as follows:

1. Run the vco without the injection signal for 2 microseconds ; let it setttle to the free running frequency; 

2. Start the injection signal and observe the phase noise...

 Well, I need a periodic vsine source to generate the injection signal in the schematic; and this is the very source of an error in my pss simulation:

" 'V0' is a periodic input signal, which is inconsistent with autonomous circuits. "

 this is what happens if I set cadence for phase noise simulation using the instructions given in the cadence Spectre manual.

I know... the instructions are for a 'normal' vco; but I was hoping that it would work for my injection locking case as well.

Question, as obvious it is by now :), how do we simulate the injection locked oscillator phase noise ?

Is there a way to conceal the periodic voltage source in the circuit so as not to piss the pss off ?

thanks,

calp.