Cadence pss+pnoise: output Noise result problem

Dear all,


I am using C@dence to simulate my upmixer circuit and want to get Output noise value. I am using pss+pnoise to simulate it. In the "Direct Plot Form", it could allow me to select "Output Noise". However, I found the result is different using this equation " Ouput noise = -174dBm/Hz + Gain + NF " The value of "Output Noise" is around 20dB better than the calculated from equation. Which value is correct? Or, any setup I am wrong?

Thanks,

wccheng

it should be :
Ouput noise = -174dBm/Hz + Gain + NF + 10logBW(Hz)

Even I use this correct equation, it still have 20dB different. WHY?

can you upload your simulation file?

---------- Post added at 23:28 ---------- Previous post was at 23:28 ----------

did you add white noise?

how much of the white noise value?

there are some white noise block in ADS, you should add it, and the software will do the calculation

I am using spectre simulator in C@dence. Any method?

Show me a definition of Gain you are applying.

Can you name the white noise blocks in ADS. I have searched but unable to find these blocks.

Can you name the white noise blocks in ADS.
I have searched but unable to find these blocks.