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I will promptly provide any detail or revise my question aimed at any feedback.

Does the profile of phase-noise power spectrum density (PSD) vary with time?

The conclusion may be that it won’t basically vary with time or it won't do that within a specified period of time?

The phase noise originates from modern communication transceiver considering the direct-conversion architecture.

Hope to be answered and explained detailedly.

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wu yi
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  • In what circuit or system? – The Photon Jun 03 '19 at 05:44
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    The fact that this is in some transceiver is irrelevant. What creates the phase-noise? Usually it is the VCO + PLL but it depends on the actual transceiver. What do you mean by "shape" and "vary with time"? As noise is temperature dependent it will change with temperature so then yes, it will vary over time. It might help if you explain **why** you need to know this. – Bimpelrekkie Jun 03 '19 at 06:35
  • I have added a picture in my question. The "shape" is equivalent to the profile of the spectrum. Just as the black heavy line presented in the picture. I am pursuing with phase-noise characteristics in time and frequency domain. So I want to know the variation of phase-noise PSD's profile. Eager to get detailed analysis.@Bimpelrekkie – wu yi Jun 03 '19 at 07:17
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    Adding more to Blimpelrdkkie comment: the profile below 100Hz is probably determined by the Crystal Reference phasenoise. The "bump" at 1,000Hz is from the loop-filter natural-frequency, which depends on I_chargepump and C_loopFilter and VCO_hertz_per_volt. Above the "bump", you see the innate VCO far-out phasenoise + any circuitry after the VCO such as Quadrature Generators, or **ANY** other circuitry that touches the LO signal. All these circuits are temperature dependent, VDD dependent, and will age, or be affected by ionizing particles. – analogsystemsrf Jun 03 '19 at 12:32
  • Thank you for your reply. It is very helpful to me.@analogsystemsrf – wu yi Jun 04 '19 at 01:32

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