Problems when doing VCO phase noise simulation

[vndjn]

vco phase noise

Hi,
When i am doing vco phase noise simulation i am getting spurs at the offset frequency which is same
to vco frequency and its multiple.
I want to know why these refernce spurs coming in VCO phase noise plot.
I am doing phase noise simulation only for VCO, not inculding any other block.

Thanks,

 

[khouly]

vco phase noise

u r not including any block
and the reference spurs apper

strange , but ur VCO is in a PLL

khouly

 

[savesandhya]

can anyone help me for designing VCO in matlab using simelectronics tool