Introduction to thermal noise and computation of noise power. More instructional engineering videos can be found at www.engineering.... This video is licensed under the Creative Commons BY-SA license creativecommons....
So how is thermal noise simulated? I though it could be simulated by adding an AC voltage source in series with the resistor, but what would the frequency of the AC source be? I also don't get how the bandwidth of the system makes a difference? Why would a resistor care what the bandwidth of the rest of the system is?
As long as the resistor is maintained at 298K on Earth, it is stable. If it is sent in outer Space, the noise level will go down as the device's temperature decreases, down to 4K (the Outer Space's temperature). That's why the James Webb Space Telescope has been sent so far away from Earth (1,5 million km) : To reduce its temperature to just a few Kelvins and reduce the corresponding noise levels aboard.
