I finally got around to have a look at Ken's matlab code for predicting noise in Plls. In cadence I simulated the phase noise for the given Hartley oscillator (fout=1.14GHz) and extracted the corner frequency and n value as descirbed in Kens paper. I then calculated the jitter and used this value to simulate a noisy vco in open loop using VerilogA. I recorded each output period and used the matlab code to plot the psd of the noise. I was hoping to obtain approx. the same plot as for the noise of the Hartley oscillator (20dB region). While the matlab plot has the expected 20db per decade slope, the frequency of the plot starts at 10e6 and goes to 10e9 for nfft=1024. This does not make sense. The plot should be located at lower frequencies, should it not? When I use the matlab PSD plot to exctract the n value from the 20dB region, it should be approx. the same as for the Hartley oscillator.

Am I missing something here?  
Regards,
Sven