ACWWong
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Yes, if you run pss using the blocker, then pnoise (use pxf to ensure you get the LNA gain right, it should be reference sideband 0 for pnoise). The pnoise sweep should be 3MHz offset from relative harmonic 1 (or absolute frequency pss freq+3MHz). Always check the spectre log as it tells you what its doing at the top of the pss or pnose run. If you use your LNA source and load as ports (ususally of 50 source port and large load port resistance to mimic mixer load) then you can get spectre to calculate NF directly for you. So you should see with a low power pss tone (ie small blocker) your NF will be the same as linear noise/sp analysis. When you increase the pss tone (for example to -23dBm or above) the NF will increase. you can print the noise summary (fill in the frequency relative if the pnoise sweep is relative) to see where the contributors are.
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