Thermal White Noise - Johnson–Nyquist noise

[berkeman]

This problem really hertz

 

[Mechatron]

New theory:

The flicker noise is carried on the 20 kHz signal, so the signal is a carrier signal. In addition to try to calculate the cut off frequency of the flicker noise. From a different think-outside-the-box perspective;
If you can calculate the noise voltage using Johnson's equation for every instance (a unit of time):
If the noise voltage is 0 at 0 ms, 1 V at 250 ms, 0 V at 500 ms, -1 V at 750 ms and 0 V at 1000 ms, don't you agree that the frequency is 1 Hz? So since the thermal radiation generate random noise and generate a noise voltage, and the noise voltage vary, then we can say that the thermal radiation actually does have a frequency on the carrier signal.

 

[the_emi_guy]

If you can calculate the noise voltage using Johnson's equation for every instance (a unit of time)

You can't calculate the noise voltages, it is a random function. It would be like calculating ahead of time rolls of a dice.

If the noise voltage is 0 at 0 ms, 1 V at 250 ms, 0 V at 500 ms, -1 V at 750 ms and 0 V at 1000 ms, don't you agree that the frequency is 1 Hz?

No. Because maybe the voltage at 100ms was 4V, and at 101ms was -6V etc. Get it?

Or maybe yes if for this one particular second this random noise voltage just happened to trace out a sine wave.

How likely would you expect this to be?

 

[berkeman]

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